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MADIIYA PRADESH WATER RESOURCES DEPARTMENTDESIGN SERIES TECHNICAL CIRCULARNO 33 (Revised)

(Issued vide memo no. 22 1 /BODHI/R&CITCI1 0 I g I lDt.30t12tr991)SELECTION OF TYPE OF GATE

ilriNfi_SJlt-G".uO,N#

A hydraulic gate is a equipment used for conholling the flow of water through anycomponent of the inigation system. Generally it holds the water on the upstream sidethough. Some gates deal with a reversible water flow in special cases.

i':e$.rE-r:

2.1 According to purpose and location of gafe:_

2.i.1 Spillway gates: - A gate used to regulate flow over a spillway.

2'i 2 Sluice gate:- A gate which controls or regulates flow. Through an opening wherethe upsueam water level is above the top ofthe opening.

2'7'3 Draft tube gate:- A gate used to permit dewatering of the draft tubes for inspectionand repair of turbine parls and draft tubes and is placed over the draft tube portalunder-no-flow condition, although there may be considerable tail, race turburence atthe time.

2.r.4 Banage gate: - These are a series of gates across the river to regulate water surfacelevel and pattern of flow upsream.

2.1.5 Pick-up-weil gate: - These are the gates provided on the prck_up_weir.

2'1 6 cross-regulator gate: - A gate in an irrigation chanaer for the purpose of raising thewater level.

2'1'7 Head Regulator gate: - A gate provided at the head of canar off-taking from a riverto regulate the supplies enter.ing the canal and to control silt entry into the canal.

2 1 8 canal escape gate: - The gate pro'ided in the canal escape, to escape sulrrus orexcess water from the canal.

2 1 9 Penstock gate:- The gate provided in the penstock to regurate the flow of water tothe turbine in a hydro electtic power house.

2 1'10 By pass tunner gate:- During construction of dam the river water is diverledthrough a tururel and the gate rocated in the tunnel to regulate the flow of riverwater.

t1l

2.2 According to the shape of the Gate:-

2-2.1 Radtal Gates:- A hinged gate, the leaf of which is usualiy a circular are with thecentre of curvature at on very near the hinge or turn-on.

2.2.2 Cyltndrical gate:- A gate in the form of a hollow cylinder placed in a vertical shaft.

2.2.3 Drwn Gate:- A movable crest gate in the form of a sector of a circle hinged at the

crest are face effect a water soak with the edge ofa recess into which the gate may

be lowered. The gate is raised and held up by the pressure of water admitted to the

recess form the head water. It is lowered by closing the inlet port to the recess and

draining the water form it. The top surface of the drum matches with the curve of the

spill-way.

2.2.4 Rectangular gate:- These are rectangular in shape and hence called rectangular gates

2.3 According to the made of movement of the gate:-

2.3.1 Vertical lift gates:- A gate operating in vertical grooves.

2.3.2 Gates rctaling about a fixed exunion point e-g. radial gates, drum gates etc.

2.3.3 Automatic gates:- A gate which functions without extemal manual attendance.

2.4 According to water head acting on the gate:-

2,4.1 High head gates:- A gate which is subjected to a water head of 30m. or more above

the gate siil.

2.4.2 Medium head gates:- A gate which is subjected to a water head exceeding 15m but

less than 30 m. over sill.

2.4.3 Low head gates:- A gate which is subjected to a water head upto and including 15m

above siil.

2.4.4 Differential water head gate: - In this the head of water is at different level acting on

both the sides ofthe gate.

2.5 According to the function of the gate:-

2.5.1 Service Gates:- A gate which operates under unbalanced conditions at palt gate

openmg.

2.5.2 Emergency gate:- A gate provided on the upstream of a service or a regulating gate

to shut off the flow under unbalanced head.

2.5.3 Stop-log gate:- A 1og, plank, cut timber, steel or concrete beam fitting into end

grooves between walls or piers to close an opening under balanced condition

t2l

automatically the upstream/down stream rvater surface at a predetetmined constant

Ievel.

I

3.1 Spillway crest gates selection:-

Many types ot gates are in use for spillways for which vertical lift and radial gates

are mosl popular in modem practice'

3.1.1 Vertical lift gates:- Vertical lift gates are generally used when it is necessary to

store a high head of water behinJ gates and where it is required to obtain large

discharges ln narow confines' It is also used in locations where the tail water level is

so high that the trunton pin for the radial gate cannot be located conveniently'

Vertical lift gates will also be suitable for spillways when the elevation of the full

reservoir level is high above the sill level so that excessive long piers would the

required to te extenOeJ on the downstream at a sufhcient height in case of radial

gates. In radial gates tf'" tut"' load is taken by the piers as concentrated tensile load

at the gate anchorages which may limit the gate size' where as in verlical gates there

isnosuchlimitation.Verticalliftgatesconbeerectedspeedily.

3.1.2 Raclial Gates:- Among the vartous typ

gate is the most economical and us

simplicity, light weight and low hoist c

becoming popular for spillways tn mo

for this type of gate is that the trunion s'

spillway discharge to avoid contact wi h floating debris etc'

Further, the trunlons of the gate shall be so located that under conditions of

maximum discharge over the spillway barrage' these should preferably remaln at

leastl'5mclearofthewuterprofile.Withgateshavingthetrunionsontheupstreamside, the trunions have to remain submerged ir water' but suitable of the trunnion

Pafis under such condition'

3.1.3 Automatic Titting Gate/ Automatic Gates/ Shutters: - Installation of automatic

gates is the most economical solution for raising the storage capacity of existing

dams and resolving water crises'

Automatlc gates are cost effective and time saving and do not need any

hoisting arangement' We are facing

gates are useful to mitigate addition

and installing the automatic gates Ex

modification and extra land acquisition'

These gates are also useful for water harvesting structures and can be used on

bridge cum barrage, Aqueduct cum barrage and in percolation tanks'

I?]

\Techno economical feasibility is required for installation of these gates

considering availability of yield, structual safety and stability of the stn"lcture and

resolve of land acquisition rssues.

In case of an ungated weir of dam where there is low head of water the

additional storage capacity between full reservoir level and maximum water level

can be between 20 to 60Vo ofthe existing live storage. By installing automatic tilting

gates this capacity can be usefully employed without encroaching on the free board.

The principle on which the automatic tilting gate function is that of common

balance. Water pressure on the gate itself is utilized to provide the opening moment

while self weight of the gate provides the closing moment. The water pressure acts

on one lover arm while self weight of the gate acts on the other. with a movable

fulcrum between the centre of water pressure and centre of gravity. The gate is

manufactured out of mild steel, supported on end girders and canies ho,rizontal and

cross girders which in turn supports the skin plates. These types of gates are useful in

remote places also.

3.2 Gates for reservoir out lets:-

Vertical lift gates, either sliding or fixed wheel type are extensively used in outlets.

The Selection ofhigh head outlet gate mainly depends upon the functional requirements.

3.2.1 Depending upon the functions thgy perform, closed conduit gates can be classified

as:-

a) Regulating gates.

b) Non-regulating gates.

Regulating gates are those which are used for regulation of flow at partial gate

openings'Nonregulationgatesalekepteitherincompletelyopenorclosedposition.

3 .2.2 Onthe basis of disposition of seals and skin plate, closed conduit gates can be of the

following types.

a) Gates with upstream skin plate and down-stream seals'

b,) Gates with upstream skin plate and upstream seals'

The former can be either offixed wheel type or slide type' where as the latter is of

fixed wheel tYPe.

Inhighearthdamswherelargedischargesarereleasedthroughconduitsortunnelsofexceptionallylargesize'economiesinthedesignwarrantusageoflargeverticallift gates of rolling type in preference to slide gates because ofpractical limitations

in the size of hoist.

The majority ofhigh head gates capable or part opening in closed conduits belong

to vertical lift gate of rolling fpe. Since the rolling to verlical lift gate of rolling

type.Sincetherollingislow,thehoistingcapacityrequiredisrelativelysmall,and

t4l

il

as the gate is capable of lowering by its orvn rveight' rope drum or chain hoist can

also be emploYed.

3.3 Selection of canal gates:-

The control mechanism provided to regulate the flow of water in canal is by means of a

gate. The main functional aspect ofthe canal gates is ofregulation of water flowing

through the canal.

The main tyPes of canal gates are:-

(i) Sliding tYPe gates

liit Fixed wheel tYPe gates.

Itisfoundthatvenrcalliftgatesalemolesuitablefortheregulationofwaterincanals in comparlson to other types of gates' However Automatic Radial Gate can

also be used in canals.

For most of the canals where the head of water is quite low sliding tlpe of vertical

lifts gates are used. For high head canal gates fixed wheel type ofvertical gates are

also used.

3.4 Selection of Penstock gates:-

Penstock gates are generally vertical lift gates of fixed wheel type'

For operation of penstock gate hydraulic hoist are mainly used ln penstock gates

the time required for opening and closing the gate is kept minimum and is expected

thatgatewillopenandcloseinaveryshortperiod.Thisrequirementofoperationisonly possible with hydraulic hoists Hydraulic hoist is also used when a positive

thrust is required for closing ofthe gate.

3.5 Selection of Draft tube gate:-

Draft tube gates are generally vertical lift gates of sliding type with sealing

arrangementonbothsidesofgateduetowaterheadonupstreamanddownstreamofthe sate.

Hoists are provided for operations of gates, which are used of regulate flow from

reservoirs for flood control, Inigation and power generation lf there are a number

of gates in a project, either travelling or gantry cranes may be used for their

operation. While this system is cheaper than ptovision of separate hoist for each

gut", th. period required for the operation of gates is greater' Hence quite often

individual hoists are provided. Different types ofhoists are used for operating gates

depending upon the hoist capacity required and the operating consideration The

following are some of the tYPes.

tsl

.tt Screrv lift hoist:-

This type of hoist is used when positive thrust is required to close the gate, though

elficiency of this hoist is low, there is overall economy because, it is more compact

than other type ofhoists. Due to the preference to single point suspension is more in

case of small gates or narrow ones like sluice gates etc. screw hoist in limited to l5

tones capaclty.

Rope drum hoist:-

This is the most commonly used type of hoist for soillway gates, because it enables

a wide gate being suspended at the two ends with common driving unit at the centre

or at one end. This type of hoist is also used for sluice and penstock gates, when

these are of self closing type and when there is no vibration of the gate' Since

vibration of gate decreases the life of ropes considerably and hence this type is not

suitable. Rope drum hoist can be manually operated or electrically operated

depending upon the capacity of hoist and period taken for opening and closing of

the gate. Rope drum hoists are normally used for spillway gates, sluice gates,

emergency gates etc.

Hydraulic hoists:-

This type of hoist is mainly used for penstock gates whele the time required for

closing is kept a minimum. It is also used where positive thust is required for

closing of the gate of in the installations where vibration is experienced' With this

type ofhoist, the oil in the cylinder acts as a buffer and dampens vibration'

Automatic hoist with float operations:-

These types of hoists are generally used for operation of spillway and canal gates

located in remote places. Where the operating personnel are not always available so

that the water can be let down when the reservoir level is above F.R.L. the water

level in canal is above F.S'L.

4.2

4.3

4.4

5.0 HOIST CAPACITY OF GATE:

5.1 The hoist capacity shall be determined by taking into consideration the following

forces which might be required to be overcome'

a) Weight of the gate along with all its components'

b) Al1 frictional forces comprising of:

(1) Wheel friction(2) Guide friction(3) Seal friction and

(4) Pulley friction.

I61

c) Any hydro-dynamic load, like down pull force/uptiit etc.d) Silt and ice load wherever en_counterede) Lifting beam, if used.

0 Any other consideration specific to a particular site.

5'2 The worst combination of the above forces, during either lowering cycre or raisingcycle, shall be considered.

5'3 The hoist capacity thus anived at shal be increased by 20 percent to add for thereserve hoist capacity unless otherwise specified by the purchaser.

5 4 The gate sha be designed for closing under its own weight (without any positivethrust to the same) and to achieve the san e, downward rbrces closing the gate whirelowering shall be at least 20 percent higher than the frictional ro..., opio.ing trr.doqT rward motion The necessary crosing/seating load shall be obtained, .,'t .n tnJgut"is about to seat on the bottom seal. The values of closing/seating load shall be greaterthan those given below.

Type of Gate

Fixed wheel gates or radialGates for spillway crest.

High head sluice gates.

Minimum seating load

250 kg f/m length ofgate.1000 kg f/m length of gate.

5'5 The usual lifting speed for such hoist shalr be 30 to 70 cm per minute. However, othervalues may be adopted depending upon the requirements.

5 6 Note:- Generally electromechanical hoist should be provided for spillway gates.However if the condition of frequent opening/shutting and urgent ope.atio.,occurs, hydraulic hoist with prior written permission of Chief Engineer E&MWRD/Chief Engineer, BODHI WRD& E_in_C WRD may be obtained.

17)

FORMULA FOIT CALCULATION OF GATE WEIGHT F'OR ES''IMATION I'T,]IIt'OSI.-BY BOOK OF DESIGN OF HYDRAULIC GATE

By : paul C.F. ErbishtiI. WEIGHT OF RADIAL GATE / SEGMENT GATE

G= 0.64(BrhH)068r

For spillway gates, and

G:3,688(B'?hH)0 52r (For subme.ged segment gates)(ln equations. B, i and Hare expressed ilr merers and the weight G is given in kN. For spiluargates. it can be assumed H-i, rvithout incurring any substantial error.2. FIXED-WHEEL GATES

G: 0.735(B2hH)o 6e7

For B2h H>2000 mr, and

G=0.886 (BthH;oosrFor B2hH<2000 m4.

3. STOPLOGS GATEThe weight ofone complete set ofstoplogs for one opening is given by the 6quation

G= 0.60t (B)hH)oro:

For spillway stop logs, and

G= 0.667 (BrhH;oore

For sLrbr.nerged stop Iogs.

4. FLAP GATESThe weight of fl.ap gares is estirnated by the expressionG=2.387 B(ht-t)064r

By the above 1'ornrula the u'eight calculation lbr gate leal'orrlv r.c- excluding cnrbccjdccl parrs lirrweighL of errbedded par1s, lbllowing ratjo can be uscrj.

Legend:

B- span of gate, rrh=he ight of gare. mH: Head on sill, mG=Weight of the gate leaf in kN (excluding enrbedded pans)

WEIGHT OF EMBEDDED PARTS

Gate Typc Ratio bchvecn rv t ol cmbcdded and rvcisht ofMinimum Maximum

Spillrva t (Red ia I GateS u brlelRed seqntentFixed-l heel ruith B,hHji000,,,Fixed-u hee I ,,virh B.hH<2000r,,Spillway stoo loS u brnelged stoo lo

IS 13623:1993Table 1 Gates anrl Hosits Commonly Usetl and Their Location

(Clause 4)

Type of Gate Type of Eoist Remarls(D Crest

(iv) Power Housea) Intake

b) Penstock

c) Surge sha{t

d) Draft tube

b) Automatic gates

c) Stop log gateswhich are fixedwheel vertical gatesoi slide type i"number of elements

Serv'ice,Emergencygate of fixed wheeltSrpe or slide t5rpe orradial gates orjet flowgate

Fixed wheel verticallift gateFixed wheel verticalIift gate

Float operatecVCounterweight operatedhoist. (Autonraticallyoperates when waterlevel reaches therequired level).

Screw hoist or ropedrum hoist or hydraulichoist.

Rope drum hoist/Hydraulic hoistRope drum hoist

a) Fixed wheel Ropb drum/Hydaulic rhese gates ^are

iiei--i1 fillf,lllfrlJ:ro,hoist discharge of flood. V"rti.d ;;i"r7iJ;

(iD

Gantry crane,Monorail These gates facilitate the maintenance ofsrane with. automatically main crest gates.operated lifting beam.

gate: should be chosen from theconsideration of factors like head-supersfuchre height and availabje width oipret e1c. However, the limiting height ofvertlcal trtt gate should be gm.

Hydraulic hoist is used for. quick closure ofgate.

Surge shafi gares are used for the rnspeciionofturmel/pensrock.Gates are meant for tlte maintenance ofturbines by preventing the entry of tail racewatei.

(iii) Constructiou sluice, Fixed wheel vertical Rope drum hoist/cbaindiversion tunnel, lift gares pulleyetc. itociisiwinches/-ovubt"

Fixed vheel vertical Rope drum hoisV EOT|ln gate crane

Fixed-wheei tyne or Rone drum hoisti Gantrysllde qPe crane

Gates are used for regulating water formreservoir to main canal. Capacitv of screw

(v)CanalSystemhoistshouldbelimitedtotit.-

These gates are used for the maintenance ofc hoist constant upstrear/dowlstream water

levels.

INSPECTION AND MAINTENANCE OF GATES & THEIR PARTS

Components ofthe gates to be inspected are as below:-

1.0 Vertical Lift Gates:

i. Embedded Parts:

. Sill beam assembly

. Roller track

. Seal seat/Upstream Guide

. Top seal seat and side guide

. Dogging anangement

ii. Gate Parts

. Skin plate Assembly

. End Verticals

. Horizontal griders

. Vertical Stiffeners

. Roller assembly

. Side guide assembly

. Lifting Arrangement

1.1 The aspects to be inspected and maintained periodically for ensuring proper operation ofthese are as under-

1. Clean the gate slot and bottom platform,/sill remove Scales formed over the embedded

parts. Check Second stage concrete for any development of cracks/leakages

2. Check the gate leaf cleaned and repainted as and when necessary according to the

procedure or guidelines-indicated in 15"14177

3. Check the Rubber seals smoothness for proper alignment. Check all nuts and bolts fixing

the seal to lhe gate.

4. Check the free movement of wheel shell Gate roller bearings and guide roller bushes

properly Iubricated.

5. Check the lubrication in the Hosting connection of the gate leaf

6. Examine lubrication and greased in all the components

7. Adjust the Roller assembly by the eccentricity arrangement to ensure all rollers rest

uniformly on the tack particularly in the closed position ofthe gate.

8. Check all welds for cracks/damages

9. Clear grit, sand or any other foreign material form guide-assemblies, wheel assemblies

and sealing-assemblies

10. Check the wheel pin coating with corrosion resistant compound

L0

2.0 Radial Gates:

Embedded Parts:(Common anchorages

Bonded Anchoraees)

Sill beam assemblY

Wall plate AssemblY

Horizontal Anchor Rods

Trunnion Girder

Trunnion girder chairs

Vertical rods

Thrust block(Independent anchorage

Unbonded anchorage)

Sill beam assemblY

Wall Plate AssemblY

Anchor girders

Load Anchors/Tie flats

Yoke girders

Rest plate

Vertical rods etc.

2.2 Rope Drum Hoist for Radial Gates:

Upstream SusDension

. Drive Unit AssemblY

. Gear box assemblY

. Hoist bridge

. Lifting arrangement

'Down Stream SusDension

Radial Gate Leaf:

(Common anchorages

Bonded Anchorases)

Skin plate

Side guide and seal assemblY

Vertical stiffeners

Horizontal Girder Bracings

Arm AssemblY

TrunnionTrunnion PinTrunnion Bracket

Tie between trunnion or Tluust block

Lifting Bracket

Independent anchora ges

(Un-bonded anchorages)

Skin plate, Side guide and seal assembly

Vertical stiffeners

Horizontal Girders

Horizontal Girder Bracings

Arm AssemblY

Trunnion

Trunnion PinTrurrnion Bush

Trururion Bracket

Tie between trunnion or Thrust block

Lifting Bracket

Drive unit assemblY

Gear box assemblY

Fixed end suPPott

Hoist chassis

Line shaft suPPort girder

Diai and Dial AssemblY etc'

t\

:' 2.2.1The aspects to be it

rhese gares "." ^. ;tj;:t"o

and maintained periodically for ensuring proper operation of

(i) Rubber Seals

1. Check the seals for leakages.

2. Check the seal for r

3. Ifreakage,. """"r,'

t ifdamaged, then repiaced.

repaired or reprac..

ive & immediate repair is considered necessary then use stop log gates tbr4. Check the seal for wear and tear and deterioration.

Note:- During monsoon period, stop log gates sha NEVIthrough seals.

' ---('"6 sdr.s snall 1\.1-vtrR be lorvered inspite ofheary reakage

(ii) Trunnion block assemb

l. Check utt ,t "

nu,'

y its anchorages

; nl _*;{JHH:::H:i":;J;;:;,, "nd

checked f.r,ish,ness

prate he Yoke girder and thrust block rs covered on cover it with mird steer

4. Check all the wel,

5. Cover the t ,nn,oo' 'or rounoness and rectifu defect

6. Remove

", ,,", JitilHffiff#bry ana iub,icate trunnion bearings orthegate with suitable water resisting grease as r

recommended by bea'ng manufactures. ecommended by bearing grease as

(iii) Gate structure

l. Check all the weld

2. Check .,'"ta;ng u"t' r soundness and rectisr defects.

and skin ween arns and horizontal girders as r.vell as between latching bracket

3 Latching bracket and skin plate with the help of magnifoing glass for cracks/defects andrectifu the defect

4. Clean all drain holes including those in end arms and horizontal girders.5. Check all the nuts ar

6 check uo*..ur fu",n

bolts and tighten them Replace damage dons'

witri werd and ,.,"r:;:::ffi:':,T:j-'- scaring and corrosion' Scaring mav be nrred

(iv) Embedded parts

t. Check all the sill bea

2 check the suir".",,J:;;:'rJ1#::1;j:--* ror crack, pitting etc. and derects.

(lz) General maintenance on Radial Gate,/Vertical gate IS:f0096 (part3)l. Check defective weld

2 check damag",_,,';;:::J;::,:,i:.,. to reprace

,l

l

i

I

jlllii

l

3. Any pitting filled up by welding and firrished and finished by grinding if necessary

4. Check the gate leaf, exposed ernbeddeil metal parts' hoists and hoist supporting structure

etc.

5; Covers Trunnion bearing with grease and when required keeping trunnion beartngs tn

perfect working condition is very important Check all other bolted connections checked

uP lor ProPer tightness'

6.CheckBoltsandtrunnionbearinghousirrgfortightnesswhereverrequired.

7. Check the wall plates' sill beams and repaired them it if necessary'

8. Check the wire ropes for lubrication'

9. Check the Flexible couPlings

10. Repairs and replacements ofall electrical relays and controls should be attended to'

11. Maintenance of alternative sources of Power such as Diesel Generating sets and

alternative drive wherever provided should be canied out'

12 The list of essential spare parts to be kept available should be reviewed and updated

periodically lt'" "ondition of spares should be checked periodically and protective

coating given for use'

2.3 Electrically Operated Fixed floists for Radial Gates

The periodical maintenance of brought out items like motor' brakes' radicons' etc ' shall be carried

out as per the manufacturer's advice/maintenance schedule'

a) DailY InsPection:

1. Check entrance to all hoist platforms are keep lock. Check all keys remain with the

alt the greasing niPPIes and

shift suPervisor'

2. Check the cursory daily inspection made of hoist and gate to ensure that there are no

unusual happenings and ensure operation when called for'

b) MonthlYMaintenance:

l.Cleanthedustofallhoistingmachineryandhoistplatform.

2. Check oil level rn gear boxes and replenish wherever required with oil of proper

3.

grade.

Apply grease of suitable grade by grease gun through

replace grease niPPle if missing'

Lubricate all bearings, bushings' pins' linkages' etc'

Check all the fuses on power lines and ensure closing of panel board covers not of

b.

entry of dust and motst'

All bolts and nuts on gear boxed' hoist drum and check shaft couplings for tightness'

Check the supply voltage' As per standard'

Check the expansion provision in case of independent anchorages'

Check all Starters are clean and free of moisture and dirt

4.

5.

1.

8.

IJ

9. Check each individual contactor to examined to make sure that it operated freely.l0 check arr rvearing parts are examined and uke remediar actron to avoid reoccurrence.I l. Check the magnet faces are clean if the contacted Hum.l2 Examine alr connections to see that no wires are broken and no connections are roose.13. Clean the surface ofthe moving armature and magnet cone which comes together14. When the contractor closes, free ofdust or grease ofany kind.15. Check the contact tips keep free from burns or p)ts by smoothening with fine sand

paper or emery paper.

16. Replace the contact tips which have worn half_way.

lT Do not rubricate the contacts. Normal. If so, stop tbe hoist and investigate the causeand rectify.

l8' check for condition of painting of various comporonrs ano remove rust wherevernoticed and repaint the portion after proper cleaning schedule.

c) Check Electrical connection and wiring:_

a. From supply point to main switch.

b. Main switch to starter.

c. Starter to moto.

d. Contact points ofstarter.

e. From starter to all lighting points, availability of bulbs and its glowing.d) Annual Maintenance:

1. Check the annual maintenance is combined with one of the quarterly2. Check all trash, sediments and any foreign material cleared off the lifting rope

,3. And lifting attachment.

4. Check all ropes for wear and tear and ifbroken wires more than.5. Permissible of mark corrosion is notice, Check the rope is replace. Refer is IS Code

for maintenance of wrre ropes.

6. Check all wire ropes check and rernove all visible oxidation7. Check all wire ropes grease with corium compound or equivalent brand.8. Adjust the rope tension ofwire ifunequal.

9. Check the overload relays and limit switches for proper functioning.l0 check tightening ofat nuts & borts, soundness ofwelds. A, borts shall be tightened

and defective welding must be rectified.

ll. Check the pulleys, sheaves and turn buckle for soundness.

12. Check the limit switches and adjust for design limits duty operating.13. Check the effectiveness of the brakes, check by stopplng the gate in intermediate

operation duly rising and lowering operation. Check the brakes and adjust ifneeded.14. When the gate is operated, Check there is no noise or chafter in the gears.

15. Check for all gears and pinions for proper match, uneven wear and adjust for propercontact and grease the gears.

!4

16. Repaint the holst components' hoisting platform and its supporting structures after a

time interval depending upon the painting schedule'

2.4 Maintenance of Electrical components of Fixed Rope Drum Hoists:

The electrical components to be inspected and maintained periodically are as under'

1. Check Starters are cleaned' free of moisture arld dust'

2. check each individuar contactor try by hand to make sure that it operates rreery.

3. Check all wearrng parrs are examined in order to take note of any wear which may have

occurred during oPeratton'

4. It the contactor hums' Check the contact faces are cleaned'

5. Examine all connectlons to see that no wlres are broken and no connections are loose'

6. clean the surface of the moving armature and magnet core which comestogether when the

contactor closes, free for dust or grease of any kind'

7. Examine the mechanrcal interlock between the reversing contactor and seewhen the contact

tips of one of the conhcror units are touching'

g. The contact tips should be kept free from burns and pits by smoothening with fine sand paper

or emery paper.

Replace the contact tips which have worn away half-way'

Do not lubricate the contacts'

Blow out windings thoroughly by clean and dry air to clear air passage in the stator and the

rotor for any accumulated difi' The air pressure shall not be too high to damage the

9.

10.

11.

insulation.

12. Examine earth connections and motor leads'

13. Examine motor windings for overheating

14. Examine Control equiPment's

15. Examine starting equipment for burnt contacts'

16. Check and tighten all nuts and burnt contacts bolts

17. Clean and tighten all nuts and burnt contacts bolts'

18. Lubricate the bearlngs'

19. Overhaul the controllers'

20. Inspect and clean circuit breakers'

21. Wipe brush holders and check bedding ofbrushes'

22.Blowoutwindingsthoroughlybycleananddryair.Thepressuresnotbesohigh.

23. Check the insulation resistance ofthe motor between any terminal and the frame

Solenoids 0Perated Brakes

1. Check all fixing bots

2. Reset the magnet stroKe to compensate for wear'

3. Re-adjust the brake when the magn"t strt'ke t"uches the value given on the instruction plate

If

4.

5.

6

L

8.

Check Brake lining and replace when required.Examine all electricai Ieads and connectrons.

Check Rubber bushes or couplings and replace ifrequired.Tighten the pins.

Check the Brake drum, clean to remove any dust or grease.

3.0 Stop Logs. Lifting Beam and Gantry Crane

3.1 a) Stop Logs for Spillway Radial GateGeneraty one or two sets of spitway stop Jog are pranned for Spiirway Radiar Gatesdepending upon the number of spi,way gate instatation. The set of stop rogs sha'comprise of nrorethan one unit pranned to cover around 200-250 mm above the FRL or the top of spirway gate. Underbalanced head conditions (both for these stop Jogs shalr be operate raising & iowering) by Gantrycrane to be located at the top of dam over the rails fixe on tne roadway over the dam with theprovision ofan automatic angering o/o disengaging lifting beam.

The Stop log units being in places, the top non-interchangeable unit wrth unique features asweil as the other inrercrlangeabre units is stored in rhe groores in various spans/bays. the torowingaspects are to be considered and attended during maintenance:

l. Check defective/damaged/cracked welding2. Damaged nuts, bolts, screws etc.

3. Examine the gate leafcleaned and repainted whenever necessary4' Rubber sears should be grinded, if required to bring it in arignment. At nuts and bolts for

fixing

5. Check all components greased and lubricated with the recommended Oil and grease only.6 Adjust the roller assembly by the eccentricity provision to ensure that all the rollers resr

uniformly on track plates particularly in the closed position ot the stop log gate.7. Clean the drain holes in horizontal girders

8. Examine that no bearings overheated.

9. Cleaned the gate slots and remove scaling over embedded pan.

a)

1.

Lifting Beam

Examine Lifting beam for both raising &lowering of Spilrway stop log units with the use ofGantry crane.

Lifting Beam shall mainry comprise of two number structural steer channers or fabricatedchannels with back to back connection to make it a single fabricated structural frame.Two side guide rorlers/Shore shal be provided on each side of the lifting beam. The depth oflifting beam/frame sufficient to accommodate to ro ers on each side located at sufficientdistance from one another to enable proper guided movement.

3.

2.

16

4. The depth of lifting beam should not be less than one tenth of the length/sPan of the liiling

beam or 500 mm whichever is more Lifting beam hook mechanism by the movement of the

hookblock'Thetwohooksaremechanicallylinkedtogetherforsimu|taneousoperation.

5. Check all the rotating part of the lifting bearn Shall be provided with corrosion resistant 0steel

pins and aluminum bronze bushing/roller bearings'

Following issues need to be considered and att€nded during maintenance:

(i) Bush bearing of lifting attachment and various pulleys/sheaves wheel'

(ii) Check the lifting aftachment and various pulleys/sheaves wheel

b) Gantry Crane

Hoisting trolley of the Gantry Cranes built on top of a wheeled mobile gantry struclure travelling

over fixed rails and is used to straddle an object or load overa workspace

Cabin, walkways, ladders and railings, end buffers, mechanical' end buffers' mechanical

equipment, wheels and axles, gantry drive unit, wire rope' rope drum' gears and pinions'

reduction gear box, shafts for gear and pinions, sheaves and pulleys' bearings' flexible couplings'

lifting hook and block, sockets for wire " gearbox covers' keys & key ways' counter weight'

wrenches and tools, electrical equipment, . "'motor, master control equipment' cables and cable

reel, wiring, limit switches,

1. Oil level in the gear b'oxes. It is very important to ensure that the corect oil level is

maintained. Over filling causes overheating and leakage'

2. Check the insulation resistance ofmotor winding'

3. Checking ofall the electrical connectlons'

4. Lubrication ifeach parl ofcrane

5. Removal ofany loose/foreign material along the rail track

6- Actuating tests of limit switches

7. Actuating tests of brakes.

8. Check all fuses in the control panel.

9. Necessary terminal connections ofmotors brakes etc' is to be checked'

10. Check Overload relaY.

11. CheckVisual inspection ofwire ropes

12. Checking of rope clamps on the drum snapped loose wire and its proper lubrication and

tightening ofbolts ifrequired. Check unusual noise/vibration before operation'

't)

17

4.0 Surface preparation and painting of HM Worl$ IS: CODE 14177(par3):

4.1 Introduction:

Painting of hydro mechanical works parl shall be caried opainting svste' for gates and equipment sha, be artended a::il::]t

14177- tgrT or larest the

I. Appling paint as fresh at the time ofmanufacture.II Removar oford paint, rust and repainting during mainrenance.

4.2 A] Surface preparation:

After the equipmeut has been fabricated, it is essential that befiapplied, the surface is properly prepared.

ore any primer and coat of paint is

The procedures for surface preparatlon are as follows:

l. All oil grease and dirt shall be removed from the surfaceXylor or white gasoline and crean wiping materials.

by the use of clean materiar spirits,

2 Following the solvent cleaning, the surfaces to be painted shal be creaned of alr rust, milrscale and other lightly adhering obiectionable substances by sand blasting. Blast clean to aminimum of Sa zllrswedish standard SIS 5900 with amicrons.

,vro,, rldru.lru Jl) )yuu wrth a surface profile not exceeding 65

3. The fig. B Sa zl7, is given.

4.2.1 Bl Shop painting:

I. Embedded parts which come into contact ofconcrete:

clean all embedded parts which come in contact with concrete as detailed above and given two coatsofcement la|{ to prevent rusting during the shipment while awaiting installation.

II. Embedded parts which are not in contact with concrete and gate parts:

'Two coats ofzinc rich primer with epoxy resin applied to al embedded parts Surface which are nor rncontact with concrete.

and its supporting structures

reaction and abrasion due to

18

The following surfaces are not to be painted unless or otherrvise specified:

a) Machine finished or similar surface

b) Surfaces which will be in contact with concrete

c) Stainless steel overlay surfaces'

d) Surfaces in sliding or rolling contact

e) Galvanized surfaces, brass and bronze surfaces'

f) Aluminum alloY surfaces

All finished surfaces of f'errous metal including bolts' screw threads etc ' that will expose during

shipment or while awaiting rnstallation shall be cleaned and given heavy unifortn coating of gasoline

soluble rust preventive compound or equivalent'

Cl Gates:

Primer Coat: Over the prepared surface one coat of inorganic zinc silicate primer giving a dry film

thickness of70t5 microns should be applied Alternatively two coats ofzinc rich primer' contain not

less than 850/o zinc on dry frlm applied to giv€ a total dry film thickness of 75 t5 microns'

Dl Hoist and suPPorting structure:

a) Structural comPonents: PrimarY

Primer coats ofzinc phosphate primer shall be applied to give a dry film thickness of40t5 microns'

FinalCoats:onecoatofalkydbasedmicaceousironoxidepainttogiveadryfilmthicknessof65+5

microns followed by two coats of synthetic enamel paint

b) Machinery: Except machlned surfaces all surfaces of machinery including gearing' houstng'

shafting, bearing Pedestals etc'

Primary coats: One coat of zinc phosphate priming paint to give minimum paint Confirming to lS

2339- 19630r synthetic enamel paint confirming ro lS 2932-19'11 to give a dry film thickness of

2515 microns to obtain a minimum dry film thickness of 125 microns'

c) Machined surfaces:

All machined surfaces of f.errous metal including screw threads which will be exposed during

shipment or installation cleaned by suitable solvent and given a heavy uniform coating of gasoline

soluble removable rust preventive compound or equivalent Machined surfaces shall be protected with

. the adhesive tapes or other suitable means during the cleaning and painting operation of other

components.

Note: if alternatives are chosen the guaranteed film thickness

sheets of leading paint manufacturers and incorporated the

Iocation and atmospheric conditions of project'

are to be taken anived from the data

total film thickness considering the

19

Application of paint:

The contents shourd be checked thoroughiy as directed by the paint manufacturer before and during

a) Brush/roller

b) Conventional spray

c) Airless spray etc.

Painting at shop can be done in any ofthe above three methods so that the paint can be madeto suit the convenient direction

5.0 Electrical System

Electricity is rypica,y used at a dam for righting and to operate the gates, hoists, and recordingequlpment, and other misceraneous equipment. rt is important that the Erectricar system is we,maintained, incruding a thorough check of fuses and a test of the system to ensure that a, parts areproperly functioning

1) Check the system is free from moisture and dirt.2) Check Wiring for conosion and mineral deposit.

3) Check all electrical fittings like bulbs, lights, loose wires4) Maintain generator to be as used for emergency auxiliary power.

5.1 Metal Component Maintenance

check all exposed' bare ferrous metal ofan outlet instalration, whether submerged or exposedto air, will tend to rust.

check the grease on movi||g parts. on surlaces like guides & track seats on which rhere rsmovement of gates they should be greased heavily.

Check the grease on friction sufaces to avoid binding.

5.2 Operation and Maintenance

' Day to-day experience on operatior and difficulties faced should be recorded in the log bookof gates

o check for special repairs to of gates, it is advisable to refer to Experts to execute it.o Inspection and maintenance experience are to be compiled in the form of History register of

any installation so as to be usefur for future designs, investigation of any failure, improperand unusual operation of gares.

5.3 The follorving precautions are to be taken before dry testing of Gates:

l. checking of all criticar dimensions and proper seating of gate over embedded parts is to beensured. Record of readings

2. Lubricated Worm reducer, plumber blocks, trunnion pin, gate wheels and gear wheels

20

3.

A

5.

b.

Removal of temPorary suPPorts

Checking of weld between horizontal girders, arms and trunnions' tees and hbrizontal girders'

cross girders and hoist bridge girders, final welding of lifting bracket etc' and are to be

welded if left over' A comprehensive check list is to be maintained'

Checking tightness of bolts between trunnion with arms and trunnion with horizontal Girders'

lock plate bolts oftrunnion pin, wire rope clamp bolts and other bolts

Increase ofunbounded anchorage one has to ensure the expansion of tie flats and yoke girder

under load.

7. The gates are to be inspected thoroughry for projection, temporary supports coming in the

way of gate movement and excess concrete are to be removed

8. All the rubber seals are to be made wet before lowering the gate preferably with water to

reduce heat generated between seal and seal seat and ensure fixing of all bolts and mouldings

of site joints.

9. Light test may be conducted for checking gap between seal and seal seat'

10. All weld tests are to be conducted'

z!

Design ofhydraulic gates, 2nd edition

ITEFBRENCES

ilI Knapp, F.H., Ausjtuss, Ub,Ug60). --, --erfall und Durchfluss im ll/asserbau, verlage G. Braun, Karlsruhc

lil:*" cates. U.S. Dept. or

ternational llater power andP., Downpull on Vertical Lift Gty6J). ates, International waler power

G^INEERS, Hydraut ic Des isnt)J) - oif Reservoir outlet strucnris,

:,"Lyo,,I i' Hvdrodvnamic-Analysis ror High-Head Leafat oJ the Hydraurics Division, proceedinss Er"iit,"iit.iti,Hydraulic Design Criteria, Hydraulic Design Chartents (1961).

22

S.Nol)r.|NT'a1

)- "v''rvorrJ quaured or trainedop€rators should be allowed to operategates.H "li;ilil##'Ju|"#n'"uut

should not be

3 "ivrsrw urc_BaLes onty when requiredpower supply as per rhe desisn isavartable.

l\oI tn ^har-+^ ^^.^ - rrvrule 6arcis uunng low voltage period

/\OI lar 2d"rcf +L^ L-^r

A .-r qJ! u,r .ur

i1l(es wnen the gate Isro lrrv vt.LNE5 wncn gates ls notoogged

-

#.-

5 ....-r,u I14 (cflance ounng pre_monsoon seasonH6 vJr y,upcr roors tor attendinsK7

^: :,:". urY test oelore puttng into

operatlon --,, vfvrulv 641tr5 wlrnout Dry testing

Norr;I";;;;r-i-'.--8

;ffiil,,,;:ij#ess or hoisr plarform.

*utt*ui'" q'r JrrPPsry malerlal on Hoist

9 H.,eqrqrv u4ll|aBco etectflcal wiflnp

which are exnosed r., "'*^--;^--"'rrH

1.0 ffii,-I IIn ralns _- : ": ^""p ts,rdr uux cover open aller dailymalntenance#71 F"..rqw wlls rupc ugntness on either

stded equallv hefnrc n^.*^+:-_ _^- ^;_.1." "y",o,s Edr.e wnen tne wrre rope isstacKed#1,2 ru

ruube urosses ourrng operation ofgates

n" "^t;:-::--- ,l5 !9, v' puwqr suppiy aner operation

oI gatesH * ^::;,,"*

yuwcr suppty Lo motors when it is;"i.:'i++i5d , , .r4

i*l)^ ":,1'."1ons and lunctioning ofI lrnll Swrtches before ol.,".or;^-

_ ^:,:"* 'ur LU uperare gate li llmit switches arenot tunctioningnrnr t^ .- i^L ^ n- _..__-15

H

! ivL Lv rwrLlu urr nolsr motors rf fbreignmaterral found in between teeth ofgeiWHEEI,Hto v!wv^ LrErluess or rtummer block,

dnve unit. line shaft cn,,nli-^ r-^r.^upsrdrs Bare tr any bolts ol.plummer

L7 EH olocK and couolinB holrq e.o f^,,-.r rLrr.rur si riu loretgn parllcles Stuck rrn in \H{'vru\.,ssbi

pr

:tween roller and roller track/wall

l::''ll tluer"+:9.=18u1,'rdLv gares wrm low oi.l level in gear

boxa-:-19

Lrr,!!r\ 'Burrcss ot wtre rope clampsoerore ooerationH ;,v!

!u,uysrare Bare rr wrre rope clamps areround loOSeH20 vprr.lrc. Bare onty when grooves are

clean wlthout Anv ^her

n,^r;^ ^.vv rrwr u1,lrdLe tsare rr rnere rs any projection, inthe grooves which ohstnrcrztN

;^:.-:: "t r'arr/ra fope/wrre ropes as approachror auendlng maintenance works at Tnmurions,trunruon girders etc.

23

LUBRICATION SCHEDULES.No

Mode ofLubricatin,'

LUBRICAMr requency

1rressure grease gun rcrvo gear_20 or

learing Grease2""", lu uuee monthsas per Site condirin-"rressure grease gun oervo gear-20 or

bearing Grease5,rr rruce months

rressure grease gunqr Pcr slae con.tr t'i^h]J,eanng Urease .;;--:i<

4 ",.", ,u Lruee monthsas per site condiri^-.n1.;^::-:-

5_"wu rlr d ycal Detore

#T:Y::rs+.--6

-.rsrv4l\l lvvel to beInaintained alwawcrressure grease gun IJeanng urease n=l-;--+

7_.."" ,rr uuee monthsas per site conditin.oLme shalt

bearinssrressure grease gun

H;il;;;ll.,l--.__-Deanng Urease .r;^^l:-:r ---

8rr I srx months a<

uear Wheels yLr Jrts Con0tnnn,,]-r'vs I

Lnassls Grease

@d."*9v'vw ur rrA rnonths as

#-++{rr!___urum shaft

10",,,, _,.u uuEe monthsas per site condiri^."

mechanism andother relatingparts

n:uro apphed rvl.r. urease /-\--r,zqce tn stx months asper site condition

;---.-_:---11

nano applted oervo rn _ 140 \Juce ln thlee monthsas per site conditions

24

nart for maintenance Schedule for GatesIS: 7718 Part III-1975IS: 10096 Part III-1982

Every Quarterly At EverYear

At Everythree years

At Every six years

General cleanliness ofembedded pa1ts, Gate hoistcomponents

in addition ofQuarterlymarntenanceschedule thefollowing areto bechecked

In addition

maintenanceschedul'e thefollowingare to be

checked

Check welds for damages at:

Check for oil level inradicons

Check thetightness offoundationbolts ofMotors,Radicons,Plummerblocks,couplingjoints

Check thecondition ofwrre rope,pulleys,sheaves,limit switch,brakes, andgear wheels.

. Skin plate joints

. Tee girders to HorizontalGirders

. Horizontal girders to armo Arm Bracings. Horizontal girder bracings. End boxes. Gate stiffeners

Greasing ofpulleys andpins

Check forsmoothoperation of

raising andlowering

Check gate

seals fordamages.

Check wheel assemblies forany

BreakageFrnz in o

ConosionMisalignment

Trumion pin, Rope drumhoist, Gear wheels, Handoperation of shaft, guiderollers, Gate wheels

Check forcondition ofpainting ofallcomponentsguide rollers,wheels

Check for sill beam, sideguide, roller tracks fordamages, conosion, pitting

Check for peration ofBrakes

Check Hoist Bridge forfoundation bolts fortightening.

Check for loose electricalconnectionsIn case offixed wheelgates)

i, Wheels are to begreased properly

ii. Movement ofwheels should be

smooth and it can

" be rotated by hand

25

DETAIL OF GATE

RADIAL GATES:

Introduction:

After Independence most of the Majoresources and supply of water for irrigationetc., Radial gates are playing major role in regin canals and other channels.

ot of problems were faced and the same werehas brought some of the limitations for the

structures. ne of planning and design stages of Hydraulic

uou.nr.]""r, ^toial Gates are preferred compared to vertical lift gates due to the following

- No grooves are required in the piers to accommodate road bearing wheers. Thisresults in simple construction and its arrangement.

- The construction of gates is simple and easy to maintain.- Due to configuration vis-d-vis its rotating axis about trunnion of the gate that load

bearing members are protected from damage by debris.- The only disadvantage is that it requires accurate construction of piers with required

shape at trunnion rever for movement of arms (in case of Independent Anchorages).

The Radial Gate and its operating system are divided into three groups ie.,

i) Embedded parts- which are fixed in the concrete to transmit the load to civil construction.

ii) Gate Leaf- curved prate and its supporting structures which transfer the water thrusr toembedded parts.

iii) operating system- Rope drum Hoists / Hydrauric hoists used for operation ofgate.

26

Radial Gates and its operatinR svstem:

Embedded parts:

Typel: Common anchorage system (bonded anchorages)

Type2: Independent anchorage system (Unbonded) anchorage system)

Type3: Achorages with post_ tensioned anchor rods.

Type4: Post-tensioned prestressed concrete anchorages.

Gate Leaf:

Typel: Gate reaf with curved skin prate supported by verticar stiffeners, Horizontalgirders, Arms, trunnions, trunnion Bearings, Trunnion Bracket etc.

Type2: Gate reaf with curved skin prate supported by horizontar stiffeners, verticalgirders and Horizontal girders, arms trunnion bearings and anchor rods.

Hoisting Arrangement:

Typel: Rope drum hoist with U/S rope suspension

Type2: Rope drum hoist with D/S rope suspension.

Type3: Hydraulic Hoists.

Radial Gates with Common Anchoraees:

The Radial gate with common (bounded) anchorages: - The hydrauric thrust on the gate istransmitted to the trunnion girder through brackets.

The trunnion Girder is designed to withstand the lbad of water thrust transmitted bV trunnionon either side and the road is transmitted through the anchor bars as bonded anchorages roconcrete piers.

- The rods are used as road carrying anchorages. The anchors are not werded to trunnion girderbut are fixed with nuts and pre-tensioning can be carried out. Arternativery werding ofadditional flats also can be done after pre_tensioning of roos.

77

t'!,i\

l!\!-/

s€c - aaD E TAIL- 8

Limitations:

1. Advantageous for construction of piers since no accurate pier shape is fequired attru nnion.

2. Since there is a limitation on the size and iength of rods available, it is advisable touse the type of arrangement upto gate size of 12M width x 1oM height max. In caseof bigger gates it may not be economical.

3. The disadvantage is, since the trunnion girder is common for two adjacent gates rn

case of failure of anchorages of one gate due to any reason, there are chances ofsuccessive failure of all gates.

The deviation in pier construction is to be carefully compensated while erection of trunniongirder to maintain the distance between centre to centre of vents.

"iirliliiil'i\:\

"u-i'. '-

El.EYAii ON

COIISOd A'GHOFAG€ SYSTGPII i WAY FIDIII GAIFq

@

Independent Anchoraqe Svstem:

The Radial gates with independent anchorage system the hydraulic thrust on the gate is

transmitted from Trunnion Bracket to Yoke Girder and to anchor girder through unbounded

tie flats. The Anchor girder is embedded in the concrete which transmits the load to pier.

'!HC€P€I'OAXT A{CHORAGE 5Y5TEi.ISPItIWAY RADIAL CATE

ECAO lRANgen rO COi€A-IEsTa4,ErLltE TlFc.r:+i Et€€al€il paqls

The advantages in Independent ancnoiages are: ) ::

- The gates can be made to suit the vent width even there is a variation in Civil

construction.

- There is no successive failure of gates in

The disao'vantages are:

- Care shall be taken to provide clearance between the tie flats and trunnion arms

when gate is belng lifted.

-- Pier is to be provided with shape during construction for movement of arms_

case of failure of one anchorage.

-l:F:ar-J

Thorough checking is required regarding soundness of weld between anchor girderand tie flats. Once thjs weld fails rectiflcation will be impossibie / difficult.Proper erection sequence and accuracies are to be aoopted to achieve goodperformance.

Arrangement requires larger width of pierswhen compared to common anchorages.

the-failure of anchorages were noticed on

to accommodate anchorages assembly

JJr,.s, r rs dr c iruopreo Tor targer size gates.gaie executed in our country is 18.228 M wdth X 18.228M heioht .

Anchoraqes with post _ Tensioned Anchor Rods:

The arrangement of post - tensioned Anchor Bars, the hydraulic thrust is transmittedfrom trunnion girder to anchor pratq through high - tensire ancnor bars. These anchor barsare housed in Galvanised seteer tubes. After instalation three rods are to be pre{ensionedon D/S of trunnion Girder to snare the equal load.

This type of Anchorages have been used for the rarges gate and the advangates are:

) considerabry ress steer is required for the bars which resurts in more compact beam.) Anchorage movement due to extension of anchor bars are virtually eliminated.> Piers may be narrower

The Inoependent anchorage systems are adopted for targer size The max. size of

The disadvantages in larges gates:) The rods aj-e to be joined by couplers,

account of failure of couplers.

F The trunnion girder is generary provided across the vent hence heavy handring anoeTectton facilities are required.

This type of anchorages are not in practice in our country. This system is provided onry inChamera proiect.

1

IRUtr,{10\ GrnDEr

-1F

0i r ri!,\.itii i}J

FL OW

i sEqtpq_rHqllqHlelllrla.L

OF Tl(ir iJ r'i3;i

5Ei ftoN-AA

Post - tensioned prestressed Concrete anchoraqes:To obtain best arround periormance of Radiar Gates the use of post - Tensioned,

Prestressed concrete anchorages (pTpS) are used.In this system the water thrust is transmitted to the common trunnion girder through

bracket- The trunniofi girder shal be anchored to the spiflway prer by a post - tensionedanchor system ri consrsts of rendons, Anchors, sheaths, Anchor prate, Bearing prares,snrms, duplicate grout and vent fitting and a[ equipment and devrces required for instarratronand tensioning the anchors. Arternativery post-tensioned pre-stressed concrete beam arsorn use for longer gate to mount the trunnion bracket.

Tendons sha, be formed from murtipre strands of uncoated steer wire, row reraxatronstress rerieved steer strand conflrming to ASTM A. 416 and having UTS 1860Mpa.

Anchorages formed by transfer of roads through the curved portion of anchor roopwill develop the furr urtimate design strength of tendon when tested in an unbounoeo

e

rA

J.

l\"

E OF TiiUNi:'N

POSTIENSION ANCiIOR RODS

/.-:.>_tr)

condition without exceeding allowable bearing stress on the concrete.seattng, anchorages will sustain applied loads without distorsion orresult in loss of prestress.

After tensioning and

other changes which

q'

RAO'A[.6Ai- - DETAILS OF IOS'I :FTCJONI DPRE,5'IAESSED CONCR€-IE ANCHORS

Large gates can be supported by narrow spillway piers.The frictional forces due to movement of trunnion brackets are elrminatedThe prestressed Anchorages put pier concrete in compression.The prestressed anchorages are ress burky than conventionar anchoraoes.

When post - tensioning force is applied at the ends of cables, the force decreases alonq rnecabtes as a result of the following factors.

- Loss of prestress due to creep in concrete.- Loss of prestress due to shrinkage of concrete.- Loss of prestress due to relaxation of steel.

- Loss of prestress due to elastic shortening of concrete.- Loss of prestress due to slip ip anchorages_

- Loss of prestress due to friction along the able(profile) and the anchorages_

Limitation: Initial cosi of anchorage system in totai is higher than ihe conveniionar svstemand not adopted for many projects.in our country.

Gate Leaf : .

i) Conventional: This type consists of skin plate with vertical stiffeners, horizontargrrders, horizontar girder bracings, arms with bracings, trunnions with bearing trebetween trunnions ( option), trunnion pins, trunnion brackets and riftingarrangement.

This bonstruction is simple in design and easy in controlling the dimensionsduring manufacture and instarration with the rimited facirities of handring. Due tothis advantage, most of the projects are provided with this systemwherever inclined arms are used tie between trunnion rs provided betweentrunnions to take care of ihe lateral load. Based on the experience it is found thattie between trunnion is not advisable for larger spans, since it has no expansion

facility and also cause failure due to development of cracks in welding at the jointbetween trunnion arms and tie between trunnion at a later date. Need constantwatch and maintenance. To avoid this it is befter to go for ihrusi pad

arrangement for bigger gates ( i.e., 15M X 10M size gate onwards) to get goodperformance.

Orthotropic Desiqn : ln this arrangement the skin plate is being built in withhorizontal stiffener, verticar girders and horizontar girders. The other componentsare same as conventional type.

ii)

l0

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calculation for the combined stresses,andling systern is required to ,.int"in

Some times controlling of dnot widery adopJ;;;;ilensions wirl be arso dirficurt task. ihis method js

The radial gates are self closused. ,ed one and hence the followjng handling system are

pe drum hoist.

e drum hoist.

rc hoist.

l1

A

J]

c9H;

EO

iffo

lSE;FS

"=e6doQE(J90.

BHz

g;EeeEieEiC

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gFgEiEE:;iiE

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Handlinq Equipments For Hvdraulic Structures

Gates are io be operated for water regulation i.e., water release for drinking,Industriarizatjon, rrrigatron, power generation and frood contror etc.,

These are two types of operating sysiems by positron. I

Fixed type Hoisting systems: These are independent hoists provided for operatingthe gates individually and used for all types of service gates.

Under this group the main types used are:1. Screw Hoists

2. Ropedrum Hoists

3. Hydraulic Hoists

2.

4.

Movable hoisting devices: These are mainiy for operation of stoplogs, bulk headsemergency gates and draft tube gates.

The main types used are: Gantry Orane, Monorail Cranes and movable hbists etc.,In case of singie vent better to go for ropedrum hoist or hydraulic hoist.

For more details refer the following lS codes for details of specification designetc,,

lS:l l22SRecommendation for design of Screw hoisis for Hydraulic gateslS:6938 Code of practice for design of Rope drum hoists for hydraulic gateslS:10210 Design criteria of Hydraulic hoists for gatesls:11733' Guide rines for design of float di'iven hoisting mechanisms for automaticgates control.

ls:3177code of praciice for Erectric over head tfavering cranes and Gantry cranesls:807 Code of practice for design, manufacture and testing ( structurar portion ofGlanes and Hoists)

16

r.

Selt 9lqEIns_qf-Eelg:

The first step in deciding handling system for hydraulic gaie is io ensure that the self

closing (gravity lowering) or not.

The gate shall be checked for closing under its own weight (without any positive

n thrust) and downward forces closing the gate while lowering shall be atleast 20% higher

compared to upward forces. The necessary closing / seating load shall be calculated

considering the net cross sectional area of the bottom seal and maximum water pressure

acting on it such that the lowering force is more than seating load However' the values of

i closing/seating load shall be greater than those given below:

Tvpe of qate: Minimum seatinq load

Low head gate: 2-5KN/m length of gate

Medium head gates: 5.OKN/m length of gate

. In case of gate is not self closing even by providing ballast accomrnodated in gaie then

one has to go for screw hoist or doubte acting hydraulic hoist for positive thrust to close

ihe gate-

Ex: Sluice gates and Conduit gaies.

. Self closing gates are being operated by Rope drum hoists, Gantry crane, Monorail

A hoist, single acting Hydraulic hoists-

Hoist Gapacitv: The hoist capacity shall be determined taking into consideration the

following forces which might be required to overcome

a) weight of gate leaf along with all its components including the weight of wire rope

and attachments and ballast etc.,

b) All frictional forces comprising of

. Wheel friction

. Seal friction including friction due to initial compression

. Guide friction etc.,

17

Note: L Consider init

or gate weignl compressive force rs l Kg/cm length oi seal Gujde friction is 5%

Note : 2. In case of slide gates, sliding friction may be considered.

. Any hydrodynamic load, jike down pull / uptift force etc.,. Silt and ice load wherever encountered. Weight of lifting beam, if used or. Any other consideration specific to a particuiar site / project.

rces during either lowering cycle or rarsrnghus arrived ai shall be increased by 2OT" to

rwise speciiied by the purchaser,

Note: No direct formuplift because ihese are o.''""'t

availdble for arriving Hydrodynamic load like down pull /rpending on flow velocity, shape of gaie, position of gate, siottuoy results for accuracy other wise nearesten_ Based on the expedences for low andch effective and considered_ For high nead

n"*"""1n,*Jr";::ff: speed for Hvdraulic sats are 0.3oM/minute to 0.7oM/minute.

most or our sates workins ; ::,.1l"Jjil ::j::#il;t:' the requirement Generarry the

capacities the speed adopted is o.3M/min to contror .,n'n

t t on' In case of large gates,

smooth operation wiih out rressdemandofair

ribration rherowe*o""or;;:]:":#:::;:ilTi::il:

18

1. Screw Hoists:

Sciew hoists are used generally for smaller vertical lift gates subjected to low and

medium head. Most of the applications manually operaied screw hoists are used. The

power operated can also be adopted if required for sluices. \ /here ever screw hoists

are used the self closing of gaies by applying positive thrusi. The arrangement is shown

in the drawing.

The main parts are: Stem, Nut, Capsten with spiral bevel or worm and worm wheel

mechanism for operation of the gate. This system can also be provided with position

indicator, and limit switbhes controlling to gate travel extreme position'

Theavai|abi|ityofstemrodsize,|engihandfaci|ityofmakingsquarethreads- is governing factor or usage, the capaciti€s normally used fof screw hoist is limited to

15t. Some are using higher capacities on special occasions.

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DETAILS OF STEI1 RON

!9EIt fl g,H^T,";itrA,,eiSHyif,:StiJ"T5i*

. .- . .- -.r"}.Jr-.'...- -;I

0E4l!:€

:-T+?;m

2- Ropedrum Hoists:

Ropedrum hoists are used extensively for operation of Hydraulic gates for all types of

self closed gates by gravity. Before going for different types and the type of hoist

selected one has to study the following :

Speed required.

Lift of gate vent width available .

Power source available.

Balancing operation'of gate maintaining the lead angle of ropes etc',

Over load protection of hoist required.

Power operation / manual operation or both.

Space availability, working clearances etc.,

Space restriction for movement of pulley blocks/ lifting beams'

TVpe of hoists :

ystem for c

. br"," " ;:;'ffi.J;::::::::;j:*",

ll. For operation of Radial gates" Ropedrum hoist with upstream rope suspension.. Ropedrum wiih dowri stream rope suspension.

Difference between U/S and D/.S rope suspension

lift gates generaily allin less space.

UP Sheam sGpensio;

Type oiEFaionGctr-.on More srnce leter ;rnirb GC

Dalancing is crittcal. Gearscapacity and reduction rat,orequired is more

advantage is used. Thecapacity of gears, and gearratto required js less.

wainteJanEe oiRope- .Sin^a .:::---------,' ,es r upes are always under-water, applvino rnnF .^--. , , .J .. .v , vpc r,ut pOUI_)dand replacempni nr .^^^ur rOpeS tSornlcult water on the gate

Hoist Bridge-Hoist brrog;l;;;;essat foi bestrayout

gtrder is requiredInterferGnie of ropes--.--.--_--

vo,crur slrjdy and locate rne, ,vrr r.. I ne rope shall be alWaystangent to the c!r;^ ^r^+^-, e,u o^irr praie Olherwrse the gate top will bend

ttre tocation EinoEt rs to Gselected after working outnecessary clearance of Hoistcomponents with movinqparts of gates

Maximum-ipaiitiesexecuted in India

22

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ROPE.

329 WRE ROPE + CONSTRUCTION, RIGHTHAND LAY UNGALVANIZED MAINUTS '180 KG/MI\42 HAVING MIN. BRAKING LOAD60958 KGS, CONFORT\4tNG TO lS 2266 1989LENGHT REOUIRED 80 M -2 LENGTHSWEIGHT = 622.0 KGS

-MOTORi10KW(15 H P)975RPM SQ.CAGE tNDUCTIONMOTOR,CONTINUOS DUTY,TEFC,CALSS "B'INSULATION FOOT MOUNTED WORKING ON4OO/440 V A,C 3 PH,50 CYC/SEC OUT PUTSHAFT EXTENDED ON BOTH SIDES,FMIMESIZE ND.]6OL CONFIRI\,4ING TO 15 325 -1NO.

E,M.BRAKE.25OO AC ELECTROMAGNETIC SOLINOIDOPERATED SINGLE PHASE BRAKE, 1OO% COILRATING, CLASS :'B'INSULATION, WORKING ON

4OO /440V AC ,50 C/S WITH BREAKING TORQUECAP= 19.30 KGltl.-1NO-

WORII REDUCER:RATIO 60:1,TYPE "U", SIZE 10" INPUT H.P:15,INPUT SPEED S75 RPM, OUT PUT TOROUE530 KGM OUTPUT SHAFT EXTENSION ONEiTHER SIDE WTH SELF LOCKING.INO

SNA 513: TC PLUIVIMER BLOCKWITH 2213K BEARING AND H 318 SLEEVESTATIC CAP = 57 2KN,DYNANIIC CAP :20.0KN

--J +--

TECHNICAL DETAILS:

NO OF HOISTS : 19NOSCAPACITY OF HOIST ' 7OT

. SPEED : 0.50M/min t10%TYPE :ROPE DRUM HOIST

D/S SUSPENSION- LIFT : 9-50 M. DESIGNED : AS PFR lS 6938 -

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Main Sub assemblies :

The ropedrum hoist consists of the following:

1. Drive unit assembly: consists of motor, brake, worm reducer and manual operation.2. End Gear Box assembly: consists of ropedrum, gear reducers, shafts and bearing

blocks etc.,

3. Dial and Dial assembly

4. Bottom pulley block and rope

5. Supporting structure

6. Electrical controls wiring etc.,

Note : only worm reducers of 50:1 , 60:1 and 70:i ratios are self locking and hence gate isonce lifted, it's never lowered by gravity even when brake is not effective or brarefails . Therefore if s more safe even for manual operation

The other gear drives are not self locking and hence the moment brake is loose thegate will be dropped. For manual operation rachet and fall system shall be added for

safety. Also a limit switch arrangement shall be provided to cut off the supply during

manual -operation

for safety.

7. Layout of Hoist: after arriving c.G of gate and lifting centers in the gate, the location

of drums are fixed. considering the pier thicknesses ihe hoist supporting centers are

to be arrived and layout is to be made.

The following points are to be considered while finalizing the layout:o The iayout is to be made such that the gate shall be easily maintained in the

maintenance chamber at desired level. The lead angle of the rope interferenceof wire rope with structure balanced operation shall be considered.

Necessary reference distances, levels and clearances shall be specified.

Safety regulation, poweT supply and operation of gate, dogging posiiion etc.,

shall be considered for fixing the column heights for hoist function andmaintenance of gates.

In case of monorail hoists and crane, hook approach and end clearances are to

be ensured

It is beiter to provide concrete columns than structural steel columns to reducevibration while operation.

z1-

\_-;/

ration of ropedrum hoist to Iift or lower the

All equipments shall be conforming to relevant Indian standards.

Separate locai control panelrmotor and Sha, ha 6^^r^^^ -,

s shall be provided for each gate hoistmotor and shall be enclosed _ r.vy,wsu ,ur eacn gate hoist located nedr the

i.e., rps4 ",,".u .",-,*1"^lji::":::i"r,"ted metat cabinets with desired ,,";;.;:i.e-, IPs4 or rp55_ Foroutdoo. 0,n,, iJ^^ ,]"torcu

rl€tdl c'l. vury rl-oc ts the best suited

Each control panel shall contain :

++*+

red protection

be included Per the

8.

28

_":-'- _'. _-.:.

t.Hydrauric hoists are used for operating various types of gates instared in nydrauiic

structure.

Hydraulic hoists have a number of advantaoes) Large force can be appried at desired speed without the need for gear boxes having

with several reductjon siages_

F High overall efficiency.

) Absence of over head structure instatatron is more flexibre for Jocating a bridgespanning a spillway or werr.

) The speed can be varied i e., different desired speeds can be adopted separatery forhoisting, normal lowering and emergency lowering. Example: for penstock gates andlntake gates

) where ever positive thrust is required for gate crosing the same can be achieved byhydraulic hoists_. For example : Sluice slide gates

Disadvantaqes or detrimental aspects are:sensitivity to communication of hydrauric fluid contamination of fluid when changingorl can resurt in a common cause fairure, an event which affects the whore system.First few years maintenance is very ress and after 10 to 12 years operation, thereplacement of parts cost is more.

Dust free cabinet are needed for effective performance_

Initial cost is moTe.

Usage

useo onty rn gravity_ closing gates.. Generally used for penstock gates for variable speed for hoisting bypower pack and lowering by gravity i.e., normal lowering andemefgency lowering,The radial gates are being operated with two number of hydraulic hoistsconnected on either side.Generally rr"O -::::i1"1

,_". :':"e the sates. Generaily the capacity wiil be on hisher sidewith less stroke. The gates which are working are in the order of upto 625t

max_ capacity for operation of sluice slide gates

The hoisiing arrangement ar(

r- -- e shown in the drawings encrosed.

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ls 10210 : Design criteria of hydrauric hoists for gates gives the generar parameters underwhich the hydraulic hoists are designed.

Lifting of gate is carried out by oir pressure suppried by pumping unit. oir uRder pressure is.rrected to the interior of the cyrinder on the stem side, pushing up the piston. The upwardmovement of the piston forces the oir on the other side of the cylinder to return to the tank_

q The hydraulic hoist consists of following parts:1. Cylinder/ tube2. Upper cylinder head3. Lower cylinder head / rod end head4. Piston

5. piston stem

6. piston seals / rings7. Eye end8, Mounting details:.

. Top eye end

. Flange mounting

. Trunnion mounreoThe materiars serection and design procedure shal be folowed as per rs 10210.

Hvdraulic operatinq svstem :

cornponents cf hydrauric - erectricar system consists of ihe foriowing components. Oil tank. Filters

. rumps

" Electrical Motors. FIow direction valves

" Pressure _ relief valves

" pressuTe switcheso pressure gauges. Piping

o Control components( relays, push buttons etc.,)

schematic diagram of hydrauric power pack circuit used for the system is shown in the drawing.

,o.r**uwHffiffi",,,."

.. Most widely used pio* .'",J",?,,t,""';:T"l'_",:?:"",T:"f i:Tff;:,"#:T.:,;",ffi?:.":? ffi1.il:""f,":1,:

ectrode type size and current and can bee operator.

Specification:

g:'i:* sha' be carried out in accordance with the speciflcations mentioned in some of the

ingI are welding of structural steel.metal arc welding for general construction in

ll - !?2 - 1970: Code of procedure for inspection of werosIS - 9595 - 1996 : Code of metal arc wetding oi c"iUon"r"ng"nuse steelsSome of the precauiions to be borne in the mind while weldinq are

ine flame cutting_ All oil, grease, paint, loosef the weld prior to welding. Notches or otnerbe ground smooth before joint is welJeo.

. shearing of prates "Tl.T,],0: permitted on edges of secondary materiar which wirl

ffiX#:i:: !:lii':,"J#'ary materiar must be machine name cut o.it "t'"liJc,'r,.t o"

"rn'"n Yrt"JlSl,llicker

than 4omm and up to 6omm shall be preheated to 65'c before flame

@@

E

34

Weldinq Processes :

. The welding shall be carried out as per the code of practrces of ls standards and themethods flnalized with the in nouse expertise.

,arO*lnu most widely used welding process in sites is shielded metal arc welding

Weld Consumables :

Weld ing of Carbon steel to ca rbon steel :

E7018 low hydrogen electrodes, confirming to specification CSA W48. i

' Materialwelding.Assemblv:

ihjcker than 60mm shalj be preheated to 104"C before flame cuttrng and or

arried out as per the drawings. Whereveremoved and grounded wherever necessary.of girders during assembly and handling

braces to the flanges.

E 308 - 16 or E 30BL - 16 Stainless steetmust be used. Alternatively E 309 - 16 orused for Ni - B to 10 steel

must be used.

electrodes confirming to specification CSA 48 2E 309 L * '16 stainless steel electrodes can be

E 308 - 16 or 308 L - 16 stainress steer electrodes confirming to specification csA w4g.2must be used.

An electrode comparson chart is enclosed. The consumption of electrodes permeter length for fillet and butt welds is also enclosed.

Storaqe of Electrodes :

All electrodes are to be handled as explained below

. All eleclrode c6ntainers arriving at the site shall be examined for damage. Damagedcontainers shall be returned to the supplier_

. lmmediately upon opening each can of electrodes the contents shall be placed in aholding oven held at a temperature of 90. to 120"C

(lS 2062 to iS t SzO I SOCrrsy

A) DOWN HEAD

b) VERTICAL

c) i{oRlzONTAL

d) OVER HEAD

e wetotng current costs from a verv smatiis enough if data of current consumpiion arehave been determjned for definitely typrcal

Some of standard values for current consumpijon per elecrrode are as belo\ru

0.340

0 372

Tack Welds:Tack welds shallsame quality and

fack welds shallorrentation during

Tack welds andremoved and the

be made by qualified fitters, tackers, or welders and are sublect to thepreheat requirements as finai weros.

be held to the minimum srTe necessary to hold the memoeTs tn properwelding but shall not be less than 4Omm and more than 70mm rong

temporary welds which are not incorporated into the frnar werd sha|| besurface made flush with origtnal sudace

P recautions for Qualitv welds:

Each bead and layer sha[ be thoroughry creaned of a| srag and spatter before the nextbead or layer is deposited

weids shall be free from cracks, tears and gross porosity Defective werds shal beremoved..by gaugrng, chipping or grinding and the joint re welded in accordance witn thespecificaiion where complete penetration welds are to b e welded from both sides, rneroot of the first side werded shal be gauged to sound metar before the second sioe rswelded.

as below.

Electrode lenoth (nrm

when welding in the verticar position, the pr:ogression shal be upwards for a[ oasses.

Limitation of fillet weld: As per iS 9595 : 1996The f.ilbi welds connecting parts, the fusion faces of which form an angle of more than

128 or less than 60. should not 5e relied upon to transmit calculaled loads at the full working

stresses unless permitted to do so by the standards of the parlicular application

The design throat thickness of the flat or convex fillel weld connecling parts the {uston

faces of which form an angie between 60' and 120", may be derived by.multiplying the leg

length by the approximate facior as follows:

Angle between fusion facesin Deqrees

Factor by which leg length is multipliedto oive design throat thickness

60"-90' 0.70

91"-1 00" 0.65.1 01.-1 06" 0.60

107.-113' 055114.-120" 0.50

Minlmum sizes of fillet welds shall be as given below to avoid cracking-

Thickness of thicker Part Size of fillet Weld

tn mmOver in mm Up to and including in mm

6 3

6

12

18

12 4

'18 6

36 8

56

150

56 10

150 12

16

l

ocations of hvdraulic qates:

For any fabrication getting full length plates and sectio s were difficult task and are

to u" rJra"l'L ;;;;; dJsired length and size bv metal arc werdins. Bv lolning two pads

by welding always have some deficiency though we take lot of precautions

The joints are cnosen at safe zones even in case of 90% efflciency of ioint th(

desired factor of safeiy can be achieved'

Some of the trps wherre the joints are proposed are as follows:.

:::roru important and hence fuil strengrh

e minimized or eliminated.possible:

of span or near by with a varjation ofano bendrng is.moder€te, No joj.nt jsng moment occur.

. No joint shall be providecbecause the project r",,"o 1^

n^

111'on flange at point (A) and (B) for safety. This is

hence advised. In our country is mostiy due to the failure of tnis joint anO

. The joints in flange and web

. ln assembly the weldingjoin e t0 be staggered as shown

ts In the girders are atso staggerecl while welding.

'@!i

iALL BUTI WELDS AREAND

a L-.- -- |

-_i

Horizontal Girder

SECTIoN"_AA

Y WELD

@

3. Welding of horizontal girders to end vertical or end box:

GIRDER

Theweldismoreimportanttotransfertheshear|oadfromhorizonta|glrdertoendbox-DuetoVibraiionunderpartla]operationthisWe|dgenera|lydevelopscracksinaspanof3 to 5 years operation. One is to be careful in doing this weld and also the welds are to

'

be checked durlng maintenance.

4. Lifting Arrangement:Lifting arrangement ls very importani part in gate where in the total load takes full

load while lifting. Hence the load is to be transmitted for at least two girders.

" The weld strength shall be sufflcient to take care of load under normal

conditionandalsoUnderbreak_downtorqueconditionofmotorloading.. The bracket ls to be located over full depth stiffener as shown to avotd

bending on YY direction to horizontal girder'

additional

'-err:-ii:l:r.-idrffi

F+

liftjng bracket shall be fixed matchlng the C.G of theG of gate afler qompletjon of mainufacture and

All othcr welds are atso more important and continuous one to control the

:i: ::j:_r^,:"d in hydraulic struclures because at the poinrsWher e no weld corrosion: rntermitlenr wercr rhtr " .,^l^:1t:1,:10 n"t o"'n"o ;:;t"]i:::Til:tT;: ?:;: Inlerm jhent weld the - -' r rs rusreo ano got damaged.. In case if one wants to go for

over the other as ,.^ .^,t:-:,,^"1 matching plates at jointare to be machined and sei one' over rhe other

"" ,"0,,,J;;;Jl::ilt"ffi:;;:"J,il:

' .l}*tler

F duly

performance thecneckrng the C.

B. Radial Gates:

the skin prate shal be made with be proposed For larger gates

shall be taken that joints ate to be Il as horizontal joints and care

used. r,,,,!r q(E rL/ utr crucily joints ( + ) shall not be

All weids welded in jig shall bre prepared with D/S opening as shown.

" ]f':::"":i:ililir""^::::,ed wfth werdins from U/s open ro faciritare werdinsafter alignment with down hand positjon

The skin plate jojnt is so located that there wjllgap from Tee weld. .

-r--{--l

--r€-+-llITll

VERTICAL TEE

be atleast 50 - 75 mm minimum

D/S ELEVATION

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Where ever the X-ray or UT is not possible it is betier to go for backing plate.

The location of horizontar l0int is made where bending moment rs ress for safety.No joint is provided at centre of span / support where max. bending momentoccurs

SKIN PLATE

,I

@

The thickness of backing plate may be up to 8mm to mm and width of

may be 80 to 1oo mm. Alternaiively if the skin plate manufacture is carried out

shop assembly the joint may be proposed as follows for easy assembly at slte

sealing run is to be made for leak proof .

WELD AT SIDES AFTERY AND ALIGNIVIENT

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irl

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:

Note: where ever shop assembly of skin.plate care shall be exercised to get accurate

width in construction otherwise gate cannot be matched to suit the vent'

. 2. Horizontal girders:

. For loining the rqquired size of plate butt welds of full strength 100% X-ray q

weldsaretobeprovided'Forbiggergatesconsideringihemateria|availabihandling facilities etc-, one or two site ioints are provided to suit the requirement"

.ForallpracticatpurposesavoidingtheSitejointwillbesafestmeihod'Theof joint may be adopted at minimum bending moment zone and

3

The typicaljoint for Horizontal girder is as follows :

ALI. B UTT WELDS ARE

Y OUALITY WELDFLJLL STRENGTH BUTT WELD

sIl.IIq& 8!

JffiH::T=r:::"n:"nJ",o"o joints w*h continue werds. And the sizes or werd ma,

The tie betweenbetween trunnions,

3. Tie between trunn ion:

'|rre re oetween trunnion is provided to take care of raterar roads as tensionsbetween trunnions,No of projects (Radiar gates were faired on account of farrure oi rie between welds..The tie between trunnion is to be welded to cast steel trunnlon. The history speaks that these weids are Oevetoping cracks after few years ofoperatron rn some projects the werd provrded is insufficient and there is norecord of we jd inspectjon.. ln some projects the welding has done only on top and no weld is provjded at thebottom and sides. people are takrng advantage if quajtty checks are not made.At the same time one has to remember these structures have to withstand thewater loads.

-ia=,

By experience it is better to provide tie between tiunnion to the gate size max

15.0M X 10.0M and for bigger gates ii ls better to go for the thrust block, so that

the lateral load can be transferred directly to pier through brackei flange'

TIE BETWEEN TRUNNION

-t

-1,

i,'

,f-

ol

ll1FLOWELEVATION

--,JTRUNN ON

TRUNNION RH

I

l,A

_J

z-t

The sequence of weldinq shall be as fo/lows:

hydrogen elecirode (7018).

ct reguired and lower the same over bottomshown'

cker Plate '

r ne ma jn oolective is io obtajn sound defect free welded jojnts

inclusions or porosiiy as revealed in non _

Hfi:;il" variaiions in the normal

aflecl Ihe functjon of the joint, it is termed as

. Sub_standard welding consumables.. Inefficient workman shio.r Lack of cleanliness' Un favourable properties of the base metaj.

6q

' Low ambient temperature and humid atmosphere.

Every fabricator must strive to prevent theinstance and to rectjfy them if they haveincreases fabricaiion costs considerably.

occurrence of weld defects in theoccurred. Rectification welding

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Typical Defects which can occur in arc Welds :

1. Incomplete Penetrations :

This defect occurs at the root of the joint when the werd metar fairs to reachor weld metal fails to fuse compretery with the root faces of the joint. As a resurt,void remains ai the root zone which may contain slag, inclusions. In a filleipoor penetrations at the root zone can give rise to cracking of singre butt werd.

Incomptete penetration in a single Vee butt weldIn a weld adequate root penetration is ensured by using :

' Correct size of elecirode.. Sufflciently high current.. Directing the arc towards the root during deposition of the root pass.

Rectification of this defect is a very costly proposition because itremoval of the entire thickness of the weld and re weldino.

2. Lack of Fusion :

LACK OF FUSION is deflned as a condition where boundanes removal ofentire thickness of the weld metal and base metal or betvveen adjacent layersweld metal.

This defect is caused by tl.re presence of :

' Scale ((rusting)

' Dirt

' Oxide

' Slag. Other non metallic substances which prevent the underlying metal from reachi

metallic temperature.

To prevent the occurrence of this defect, the following steps should be iaken :

Keep the joint surface clean

Use adequate welding cunentDe slag each Weld pass thoroughly

Place weld passes correc y nex to each other

Lack of fusion is rectified in Ure same way as lack of preventton.

3. Undercut:

This defect appears awerd pass .ro

'. ;ffi:;fi""J-"JT::f or dis - continuous sroove ar the toes of

Undercut in the vertical leg of a horizontal and vertical filel weld.It occufs prominentiy on the edge of a flret werd deposrted in the horizoniar position.. This defect is usually caused by :. Excessive we,ding current

, Too high speed of arc travel' Wrong electrode angle or excessive side manrpulation. Also causes due

Note : In the case o, ,o o.ro or improperly formuiated electrodes.statically |oaded structures the presence of small andintermlttent under cutting wirr reduce fatigue endurance of the werded jointand hence it should not be permitted.

Rectification:

procedure for partrcular steel. g should correspond to the recornmended

4. Over lap:The defect occurs at the toes of weld and consists of weld _ metal whrch hasover flowed on the base

iso,atedintermit,"",;;;;"ili:i j',T1;JJIT:Ti:HHJ',llrf i"i;J":il,7an apparent jncrease in the weld s jze.

Cause:I lt is occurred

metal flows

Rectification:

Slag inclusionsWhile non - metaliicmagnification.

Causes:

an electrodecoupled with a

in relation to thetoo low welding

by the wetd

welding position, andspeed also promote its

rn leg lengthsag and causes

ln the figure.

Overlap in a horizontal_vertical fillet weld

Slag inclusions in a single-Vee butt wetd

are detected by the normalinclusions are observed in

non destructive testing methods.the weid micro structure at high

rs made in theoverlapping in

Slight and intermitteni over lapping may be ignoreo rn statjcally loadedsrructures, but it should not bacr as stress _ raises, ";J:'T.'H;.J ilTffiilil ;lr?H'::::ffi:J,,il:excess infused weld metal. Care should be taken to leave rne smooth surface.

Non meta,ic particres of comparaiivery rarge size enrrapped in the weld metaiare termed as slag inclusion.

SIag jnclusions usually occursthe slag between the disposiiion of sualso be caused by heavy mill scalepresent on the surface

ff :lT:ffi :tx;f ':fi Tiil"T;T.Til::::';[;ff ']:ilil::;

The melting chz

v s cos ty o'he rust n g :#:::: :; j:ililJil"::T:T:,: T,.:' H,l',i:;

::#l""f];l freety to the surface or ti e wuro pool and easily removabje on

.'Prevention:

I Use proper welding consumables.I Keep joint surf'aces (especraty gas cut surfaces) ano oare fi,er wires perfectiy c,eanano ctean the base metal thoroughly before welding.r Avoid under cuts and gaps between deposited perfec,y ciean and crean the basemetal thoroughly before welding.r Avoid under cuts and gaps Detween deposited passes.r Clean the slag thoroughly between weld passes.

The strength of welded joint may be considererncrusions or eronsated rines or incrusions a*he _Jilff::":.jtrffi;T:.lsometrmes give rise to radiatrng hajr line cracks. The presence of small, isojatedgloburar incrusion may not however, seriousry affect the static strength of a joint andrnese may normally be disregarded.

Rectification:The portions of werd.metar which contain srag rncrusrons must be removedand then filled wiih sound wero metal

6. Porositv:The presence of a group of gas pores rn a weld caused by the entrapment ofgas dunng solidification is termed as porosity.

O_4

The pores are in the form of smat sphericar cavities erther crustered rbcary orscattered through out the werd deposit. sometimes entrapped gas gives rise tosrngle large cavity, which is termed as a brow hore. In some rarer cases, erongatedor tubular gas cavities are presented these are referred to as prprng or worm holes.

The gases are evolved by the chemical reactions In fie welding are thesegases may have high sorubirity in the morten werd metar, but as the metar soridifiesand cools, their solubility decreases rapidly and they are revolved from the metal,sometrmes'if the werd meiar soridification and cooring rs too rapid, the gas getsentrapped in the form of porositv.

Causes:

chemicaly imperfect werding consumabres for exampre deficient in deoxidizersFaulty composition of the base metal or electrode wire for example, high sulphurcontent.

Oil, grease moisture and mill scale on the joint surface.Excessive moisture jn the eiectrode coating or submerged _ are flux.Inadequaie gas shielding or rmpure gas rn a gas shielded process.Low welding current or too long an arc.

Quick freezing of the weld deposit.

Puddling of the weld metal and use of preheat or higher current allowsufficient time for the dissorved gases to escape from the werd metar. presence ofsmall, finally dispersed porosity is norma|y not expected to affeci the static and evendynamic properties of a wetded joint. However excessive porosity blow hores orptptng must be guarded against as they seriously impair ihese properiies Theirpresence is detected by the conventional NDT methods. The defective portions mustbe removed and re-welded.

Crack :

crack is defined as a discontinuity caused by ihe tearing of the metar while ina plastic condition (hot crack) or by fracturing of the metal when cold (cold crack). ltrepresents a faiiure under stress of a metal when it is behaving in a britfle mannerie., it is inclined to fracture without deformation.

I

E

!

I

1

.

'7

or rn the base metal. Cracks-'-',,vsrze trom large cracks which can be

of Jine and they may range in

Cracking can occur in the weJd metaljmay be classifred according ro tocatid

exkemely smail fissures which are d,mrcro cracks) Typical cracks occurnng

eye (called macro cracks) toaro ol a microscope (cailedare as shown.

found to be coated with the b,, ^ ^^-, """""u rr'r r/rs surrace'

rue scate or possibly black scale.

Classification of cracking according to location in a weldment :

1) Weld metal crater cracKtng.

2) Weld metal transverse cracKrng.3) Base metal heat affected zone transverse cracking4) Weld metal longitudinal cracking5) Toe crackrng

6) Underbead cracking

7) Fuslon line cracking

8) Weld metal root cracking.

Hot cracking occurs in a soridifying metar at the end of the soridification range,when this last portion is still liquid and the mass of the metar is unable to deformwithout cracking. At this stage when vibratjonal or contractJon stresses are imposed

@

I

indicated by arrows

Sbrinkage stress--

Stage'1Shrinkag€ stress

Stage 2

while hot cracking propensity increases wiih increasing joint restraint, it isreally the presence of certain undesirable low - freezing compounds formed bV stravelements which promotes the phenomenon

Causes:

The hot cracking iendency caused by phosphorous, sulphur and siliconincreases with carbon and alloy content of the steel and hence high tensile steelsmust have lower percentage of these elements than in the case of mild steel. Thisapplies as much to the weld metal as the base metal

STANDARD TIME FOR FILLET WELDIN

;rze oeld Inmm

/

Time in min/m

_11.28l8.53

Horizontal fillet weld

Electrode Dia J consumption inin mm I Electrodes/m

I tength

Down hand fillet weid \ /

Time inminlm

9.02

Erectrodei "on"t*o,,on

Dia in mm I Elecirodes/m_____ _.1____lelsth

3.15 I 4 oo

16 92 | 12.64 I11 94

4.0 | 2.73.15

315t4.O

3.15 l4n

3.2

51t34

8.1 I 5.4

3.0/31

30/40

3.0 / 7.5

3.0i 1161

3.15 / 4.0 | 5.014_38 / 10 74

6.0t40/32

26 23 I 19.59 3.15 / 4.Ac

8

10

12

v_16

9.3t62 22.84 / 11.a6

34 69 I 25.91 / 24_6 3.15t40/50

_ 4.0 / 5.0

12.3/8.2/6.6

liteo

21 04 4.A I 5.0

26 31 5.0 / 6.30

?o a/4 5.0/63r)

55.04

73.94

5.0 / 6.30

50/6.30 3.0/166

95.86 5.0/630 3.A | 22.4

l

"'"' Sffit;ierectrode length

In" "o:1. ii-:s inctudes the fotrowinsr. Jet up elements:

: 450mm: 50mm

A.1.2.

E-

tl1. Electrode burn-ng time

E rectrode changing time.

Machine set up

srag removal time.

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lntroduction:

^?:ou:o parts, gate Jeal hoists and its supporting strucrurescorrosion due to climaiic c

s acting on it. otherwisu ondition' biochemical reaction and

ment of pafts may o"""r"tT^t^:^111'pments may deteriorate

equrpment and to increase ,, stlY' Therefor; *';;":

necessary and such replacement

main purposes. :he rire. or o"*.. *"Li,.H,i"fini;:tff;[ij"l:TJ:. The first one is to protect the sieel from corrosion.. The second for decorative appearance_

Painting for hydro mechaniceri' u p"inti n g ;i; '-, ; #1 r" j:",:H n :ffi i"" :ffi"T :: ; ii lJ ;, "' o r, ates t

L Applying paint as fresirI Removar or o o o;.;:.,:l'l;o''ffi:ffiiT::l,,i"int" "n."

The procedure for sufrace preparation shail be as forows:

' weld spatters or any other surface irregurarities shalr be removed by any suitabre meansbefore cleaning.

' All oir grease and dirt sha, be removed from the surface by the use of crean materiarspirits, Xylol or white gasoiine and ctean "

iping *"i.ri"f r.

exceeding 65 microns.

,"\-J.

. The fig_ B Sa 2/z is given.

tr

@

FoT more details of cleaning method refer lS 1477 (paft-j ) _ 1g71----- - -----_sudaec-ofslaiRie-ss ste'er, nicker, bronze and machined surface adjacent to metar workbeing creaned or painted shat be protected by maki g tape or by other suitabre meansduring the cleaning and painting operations.

Primers shat be appried as soon as the surface preparation is comprete and prior to thedeveropment of surface rusting. In case there is considerabre time gap, the surfaceshall.be cleaned prior to prjming.

of concrete:with concrete shall be cleaned as detaireo

awaiting installation. Io prevent rusting during the shipment while

ll. Embedded parts whieh are not in contact with concrete and gate parts:. Two coats of zinc richs u rr"

"e wr,iii .; il' ; ::n :i"# J":}:5i':"T'jT,",#T.:l:::":" T;atmosphere or submes ha' be ro | | owed

', J'""i J]If: jT::l :iffil,:r"., H;_:: ;: il ":"r:,#:

pait so as to get a dry firm thickness of go microns in each coai. Totar dry flrmthickness of paint shall be 3OO microns.

' surfaces not to be painted: The fotowing surfaces are noi to be painted unress orother wise specifieda) Machine finished or slmilar sudaceb) Surfaces whlch will be rn contact with concretec) Stainless steel overlay surfacesd) Surfaces in sliding or rolling contacte) Galvanized surfd.ces, brass and bronze surfaces.f) Aluminum alloy surfacesAll finished surfaces of frdur ng sh pment

", *h "'i;:;ffl:,ff1,::'.::ii=;::::.r:ff ]il;J?.1lll,illl;;coating of gasoline soluble rust preventive compound or equivalent

'Gates:

' Primer coat: over the prepared surface one coat of inorganic zinc siricate pnmergiving a dry firm thickness of 70 t 5 microns shourd be appried. Arternativery two coatsof zinc rich primer, whrch shourd contain not ress than E5% zinc on dry firm shourd beapplied to give a total dry film thickness of 75 t 5 microns.

*ryi,; Two coats of solven_______________appl jed-.af r,ro*, ,,.r11ottt"l

d"b;;;;r:;;::t ress coai tar epoxv paints rhese sharl be

,r, " n o t o " lli" Jff *L,f;ill Tff

".T T :; T, :,:" ffi #. J, ;#:T#;

hail be applied to give a dry film thickness of

i|']Tl?""i machinery incruding gearing'

ospnate priming paint to give minimum flimnecessary. j oiher bought out items .tr.,, i; o.'."6"'i

c) Machined surfaces:AIr machined sudaces of ferrous metar incruding screw threads which wi, beexposed during shipmeni or instaration sha, be.cieaned by suitabre sorvent and

ranteed film thickness are to be arrived fromtufacturers and incorpofated the totat film

. tmospheric conditions of project.

@*,

. Rusiing is severe or. :i1.,::?r:ldu::::::,

has damased the primer coat exposing the metar and is norrced. The laint film has erod

carry outfresh paintino. ed badly' the scrap of entire paint fiim to the base metal and

Note: In case of mainten-anand repainting.

tce and renovation: Refer lS 14 7 (part Il) - 1971 for checkinq

:

and descaled by either mect moving the old paint fhe surfaces shail ire derusred

a) wire brushing , a"r",t"n'"""u by one or more of the methods'

or abr.asive paper rt rg' and chipping sand paperi g or cleaning with steel wool

b) power tool cleaningc) Elame cleaningd) Sand blasting or shot flasting ande) Chemical rust femovat.

):::'.rt['ff1,""t"T""::l*tion shalr be decided based on conditions existins. Aftersome are painted without ,.",'"0

o" ""

originaily proposed

and deteriorate fasterthan,tlffi[l :'1"*'"t and rusting this will amounts to no painting

Ui4[-s4flLc thoroughty as directed by pain manufactua) Brush / roller rer before and during use

b) Conventional spray

1971

ses and remedies

The carrying oti'"rn o"ffilwing conoitions:. The rusting is noticed ajl over the surface or

I ne following steps involved .

1 ^-^^-_,

. tn Inspection of painting are

2. Viscosity test of paints

1. Generar inspection b";;. " v"'t tttr ts dre

2. viseneih, r^^. ^, ) and dufing painting

3, rhickness test _ using Elcometer;pection gf general appearance of flnished work.

General: The aim of ir

Idli ;*r, ::,:ffi :il',, fl *t":l:i H'-# :i,l: ?il Hfi :' in progress. Any test ."","0

",n l"^':::j':"'"

rneans a close supervision while the work isnsture, should be either

ried out should be non - d(

general appearances, or brestricted to areas *n'"n

":t"u""ue

nature or' if of destructive

comprere repet*ion **" *l,.*nu"n ""t n

'' ,"""il;":::r:,: :"""T;T,#ilT:"lil,t"jt:

. In.:lection of surfaces prior to painting: lnspection

I' adicle is to be painted for the first time or is to be ,.uo",nJtJ.'noo" will depend on whether an

-":,T;::H::,ilT:l painted): rhe roirowing shail be decided by inspection:

b) The iniermeo,"r" oro"un'nn

feasible or recommended:

c) The painting ."h"dul " treatments to be applied' if found necessary;

performance.or,*olj,T the specifications for the paint for

"n.rring th" particurar

d) The method of application, whether by brush, roller or spray.

OId Work (Which requires ra) whether the un,,ru ur,'"o"tn*ing):

The following shali be decided by inspection:

b) whetherrepainting** :;l]:::::;;J,"J:":::.,,. r''|'vvqu'

'@\::-/'',j ,r_:--_

For ascertaining whether the oldcomplete removal_ts necessary,em ployed;

paint has deteriorated@!@ "n e*t"nt that its

th,e following test for embritflement should be

A square coin such as a 5 paisa coin shair be pressed with the straight edge on anangle of 45' againsi the paint firm. This wiir resurt in a chip of paint breaking roose from thesurface if the paint has embrit ed, lacks adhersion andembritted, ii wir curr o,., nnu"r up i,-n;J "* ;il:-il"t;:::':" I

.l:,T:H l:combined with an examrnaJion of the paint fiJm through a magnifying grass to observe rneextent of cracking and a paint firm which does not show fine hair cracks under it may beconsidered as perfecfly sound.

Inspection during prqparation of surfaces:

1. Cleaning and Degreasing. At the work _ site a visual and physical inspection isaoequate A degreased steer surfaie is duter in appearanie than one which is evenslightly oily wiping the surface with a piece of white cloth will show if minute traces ofgrease and dust have been refi on the surface. when steer is being degreased by wipingthe surface with mineral turpentine (or any other solveni), it is important to watch thecteanjng rags afe washed or changed regularly.

2. Derusting and Descaling:a) sand brasting: the most saiisfactory method of removing rust and scare is by sandblasting The criterion of inspection shourd be that the steel after sandbrasting has agrayish white meta|ic appearance. The surface shouid be uniform in coror and srighryrough only such a uniform appearance ensures that the surface has been thorougnrycleaned.

b) Hand Scraping; No defnite method of inspection may be ,aid down for hand scraping. rtis unreasonabre to expeci hand scraped surfaces to be perfecty crean, and for purposes ofinspection, air Ioose rust or scare ( and al roose paint in case of repainting) shaI have beenremoved.

c) Chemical rust removal:shali make sure ih,+ \,,.6h;^^ ll

,n".:r." of chemical rusr removal ( pickling), ishall make sure that washino .116. ^;^r_,j__ ,ur( rcriovar ( ptckling), inspection

J :r "'::lr'r]s after pickling has removed aii traces of acid. Ail work nrono-shall be inspected n",ti.rturty in in""""rriit" .oI work pieces

corners.

rt is important to inspect the work to make sure that no time is arowed for fresh rustor. other contaminaiion to take place between theprotective trearman+ r*^* - -,. recleaning and the intermediateprotective .treatment. Insoectinn ^r +r-.^ ..__!

- - P'vv'sqrrrrrg drlq rne Intermediate

;x,;:nim:itr"J;,::"::,#ili:::::J".rff::,::"::1t;n accordance with manufacturer,s recommendations.

" lff::i::[: ilil'::":"*t arter pre creanins or pre treatments; thar any

may occur in the interim period is removed, that specialprecautions are taken when painting after galvanizing; . -" - ' vv' ,"qr r

b) That no painting is carried out when there is danger of dew;

c) That tools used are clean and not excessively worn:

cl) That the paint in the (

inspected to make ",,H;;:,:"j:J:|]1.H:: prior ro apprication; that drums aTe

e) Thai if paint has thickened because of rong siorage or because of the evaporation ofthe soivents, iis vrscosity is adjusted as recommended by the paint manufacturel

I That each coat is a'owed to dry sufficienty but not excessivery before apprying theforlowing coat; that manufaciurer's instructions for drying time are adhereo ioproperty; and

g) That every individuar coat is properry appried, reasonabry rever and smooth and freefrom runs and,holidays, (minute uncovered areas).

: When inspecting general painting work

.r )

while in progress, it should be ensured:

66

1. Viscosity Test of paintorisinar va/ue

", ;":;';::t A.simplecheck

is toverirl

cornparins the times o, u"lL9 o"lng n" .ou;; ;"1

the viscositv of the paint with its

d m e ns on s " * o.",o"o *,1i ::,H: 11*il;;] ;:[h;*il::rT ::::":J

2. Thickness test: The- thi(alr coats apprie;.;fiIi:::ess or primer paints as wsenins of the rhickness Jllo"o.

*,,n " ;;;Jerl

as the total film thickness of

srandardized rest b*s "r"

'^utno is checked ;r;;';';t""'

lt is impoftant that ihe

rnstruments ljke the Eicomsr'rppiied wth every,""nurtnu

test and for this purpose

ha nd I ns o, ",.n,n*,ilff";::: ; "'i#",J*ff ": il'';

"':,:,"j;: ::l:Y retain their accuracy.

OJ) (-l;

PossibGJauGsuggesTeaEmeo.es.----oirtvai%

cun stronGa too &G tolGGurracJ Strokethes@rrigser@(when stroke does not .go

beyondobject)

Operator should release the trigger afterevery stroke.

oun"trok%surface.

Gunshouldffithe surface.

Caint appileO-too nEffi Regulate flow-f plipiPaini thinned too much, Addtheco@

measure.

1.0 Defects in finish :

I

s.tlo | --FossibE canse Suggested rGmEEGirty air cap anO-nurC-tip--lCEiortEO

spray pattern)Removeairc@

I nsufficient oiEcorreFovErlapping ot Follow the previous stroke accuEGiy t,o

deposit a wet coat.Gun stroked toJ rap;l1y 16ffi1lg !f Avoid 'whipping anO Ge Tef inerate sf ow

Gun *troked atrrwong--ingG- t,c lir"-s u rface.

Gun should be stroT{ at righa;;o6 to

Shoking too tarlromGurfaio Stroke tSO toZSOmm GEGurfacJI oo much air pressure.

Use less air presiure as neceGarn

g,

- 4,

PossibtEEuGsusgestedEmEEiG

Paint not thinned out sufficienfly. Addthe"%solvent by measure.

Not depositing a wet coat. cnects%and stroke.Gunstr@

the paint.Avoic'w6strokes.

air pressuEor reduce nuia pressura-

Using wrong air cap or fluid irozzle.setectc%and feed.

cunstroTedroo-f a--rfiihe-.-s,fieC Str"k.t.t%overs%sprayed surface. Spray detail parts first. End.\,vith a wet coat_

l. Excessiv"-Fiilt Loss _-

PossibteiiuGSuggesteo renredr.es--.---.----Not'tris-erinfl thelfi-aG;ch- ltshould%

Stroking at wrong angle dErface Gunshouto@Stroking gG-toqEafrom the surfa;A stroketne@Wrong airJlF oirrLrr-o tip. Ascertain anO uGiorrect iet uoAir pressuEGEo h[h. Useiheteaffi

PossibteJauGEsuggested reEEEG

Too high air pressure useteas@necessary.

seratms pasr suffaFof G;roEuct Reteasetri@Wrons arr;torluEj,p.-

Ascertain?nd' uGiorEEt Gluueun stroteo too Ei}6m-lE6!uEce.- Stroketne@Materiat tF-lfied ou=-t iofiuch Add the corrGGmEunt

Too humid an atmospheresprayourin@slow syspepsllng solvents as advised by.themanufacturers.

Possible cause-Suggested remeOG

'. ,, 'r ^r h^;;;-;-.:-;---i-----'-:-----.-_e, v, pc,r r. luun oegtns to spuiter). Add paint, corr.fi out and strained.SettleO, cat<eC pr-fiE-ent ntGking gfitip. Removeobstrffi

crit. dirt, pa;flG-efclocktng sun

tip, fluid valve or skarner_

Cteansprayg@paint. Always strain pa jnt before using it.

lv. painrwilno@PossibteiiuG

suggesteoiemEEesLack ot air pressur.n preGure tink Check for leaks or lack o--f air entlyAir intake opdins jlEeoi pressuretank lid, clogged by dried up palnt.

Thisisacomffiperiodically.

Leaking Gsled on tanGvel eplace wiih a ne@askA

' fj-.r' @

*****

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L_ Sglgftpf._ co n_sta nfl y.

Possible cause Suggested remediesFluid nozzle not tightened to spray gun Tighten securely, using a good gasket.Leaky connection on fluid ruoe or

needle packing (suction gun).Tighien connections. Lubricate packjng.

Fluid pipe not tighiened m tne

pressure tank lid.

Vl. Paint leaks from spray gun

Suggested remediesFluid needle pacing nut too tignr. Loosen nut. Lubricaie packing.

Packing for fluid needle dry. Lubricate this part daily.

Foreign particle blocks fluid tip, Remove the tip and clean.

Damaged fluid tip or ne€dle. Replace both tip and needle.

@