A-728 Series 2" Angle Valves Installation Operation Inspection Maintenance

Transcription

1 Installaton Operaton Inspecton Mantenance Doc. No. A-728 Seres Rev. 2/17

2 CAUTION: IMPORTANT SAFEGUARDS Mdland valves are used n connecton wth a varety of products, many of whch are hazardous materals and could cause serous njury or damage. Always use extreme cauton and proper equpment when nvolved wth hazardous materals. Ths valve should only be handled by qualfed personnel. Read all of these nstructons carefully before proceedng. SAVE THESE INSTRUCTIONS! Doc. No. A Rev. 2/17

3 Installaton Instructons CAUTION: Be sure the car s empty and clean, and the work area s free of hazardous chemcals, before removng a valve or nstallng a new one. 1. When the old valve s taken off, put a soft rubber plug nto the openng n the cover plate. 2. Wre brush the stud threads so there are good clean threads wthn 3 /4" of the cover plate. Mdland makes specal thread des and holders to clean and re-chase rusted stud threads. 3. Take out and throw away the old gasket, beng careful not to scratch the metal n the bottom of the groove when removng the old gasket. 4. Examne the sdes of the groove to verfy that It contans no dents or burrs. Snce the valve fts tghtly nto the groove, any peenng over of the edges of the groove may make t dffcult to properly seat the valve s tongue nto the groove. 5. Up to ths pont, the new valve should have been kept n ts orgnal shppng contaner. Ths wll keep the valve clean and protect the tongue from gettng ncked. Cradle the valve n your arm and use the handwheel to make sure the valve s n the closed poston when t s bolted onto the cover plate. 6. If the valve s recondtoned, or a retested one, nspect the tongue by runnng your fngernal around the edge of the tongue to be sure t s free of ncks, gouges and burrs. The tolerance on the tongue s plus or mnus.003", so any rregularty n ths surface wll make t dffcult to seat the valve on the cover plate groove. 7. Take out the rubber plug n the cover plate openng. Holdng the valve by the handwheel (tem 1) lower t slowly onto the studs. Then gently lower the valve down on the cover plate and move t back and forth untl you feel the tongue go down nto the groove on the cover plate. Hand tghten all four nuts. 8. Tghten the nuts a lttle at a tme, gong alternately from 1 to 3, then 2 to 4. Specal crowfoot wrenches wth 3 /4" drves are avalable from Mdland for tghtenng the 3 /4" heavy hex nuts. Do not tghten down too much on one sde because ths wll cock the valve at an angle and make t mpossble to get a good seal on the gasket. 9. Torque the nuts to a level prescrbed by your engneerng department. In the absence of a recommended company practce, on clean and lubrcated threads, t should be safe to torque the 3 /4" nuts to 150 to 300 foot-pounds. 10. After the valve has been tghtened down on the cover plate, the valve should be closed. To seal the valve t usually s only necessary to torque the valve handwheel about 20 to 30 foot-pounds. Usng only the handwheel, wthout a cheater or handle extenson, t s only possble to exert about 45 to 50 foot-pounds, whch s an excessve amount of torque to close ths valve. Under no crcumstances should a cheater or handle extenson be used to close ths valve, as overtghtenng wll damage the valve s Teflon seat. 11. Inspect the valve for leaks. Follow your company procedures n ths testng. The prmary areas to check are n the sde port area, the packng gland area, and the flange connecton between the cover plate and the angle valve. In order to check the seat for leaks on an nstalled valve on a tank car, pressure may be appled to the outlet flange wth the valve closed and lookng for any pressure decay. Keep n mnd that some conpensaton would need to be made for pressure changes as temperature changes. Ths s recommended n the event that there Doc. No. A Rev. 2/17

4 s no procedure n place from your company to test the valve s seat when nstalled on a tank car. When closng the valve hand-tght, f t does not seal completely, remove the valve and send t to the valve mantenance department for rework. 12. A placard wth an adhesve backng has been provded wth each set of valves. Ths gves mportant operatng nstructons. The placard should be placed on the undersde of the hnged protectve housng cover for gudance for those usng these valves. Operatng Instructons NOTE: Conform wth all applcable Transport Canada, AAR, DOT regulatons (Parts , , etc.) other governmental bodes and your own company s operatng nstructons. 1. It s mportant to bear n mnd that you should not use a cheater or handle extenson on the handwheel. Excessve force wll shear through the valve s Teflon seal, makng t harder or mpossble to close off. If the valve s leakng at the seat of the valve, and you can t stop t by a frm closng (by hand) of the handwheel, tell your supervsor that the valve s defectve and must be removed for reworkng. 2. Examne the ppe plug. Be sure ts threads are clean, free from corroson and not worn or crossed. Also look at the threads on the sde port to see that they are n good operatng condton. 3. Ths valve has an adjustable packng gland. The adjustment s set at the factory and normally needs no adjustment on new valves. The packng lock nut (tem 21) can be backed off by usng a punch or drft postoned on a corner of the nut and tappng t to loosen the nut. Then wth a 1-1 /16" wrench, tghten down on the packng screw (tem 8) and then retghten the lock nut. It s only necessary to snug the lock nut up snce ts prncpal functon s to keep the packng screw from unwndng f the stem were to bnd on the packng screw whle openng the valve. Mantenance Instructons NOTE: It s mportant that a perodc retest and preventatve mantenance program be establshed. The AAR has establshed a retest nterval for the maxmum length of tme between retests, and ths schedule should be followed. Your company s exper ence or your knowledge of the servce condtons could dctate a more frequent retest program. Before startng to dsassemble the valve, open and close the handwheel to run the stem (tem 2) up and down to be sure that the stem s not bent n the threaded area and s not bndng n the threaded part of the body (tem 4). Bent stems must be straghtened to proceed wth the dsassembly. Valve Dsassembly 1. Put the valve n a vse, grppng t on the flat faces of the 6" square flange, wth the stem horzontal and the sde port on the top. 2. Remove the ppe plug (tem 16). 3. Take off the 4 sde flange bolts. 4. Screw a threaded npple about 10" long nto the removable sde outlet flange (tem 7). Move t back and forth to loosen the flange and work t out of the valve. It may be necessary to nsert two screwdrvers (180 apart) between the flange and the valve body to pry t out. 5. Usng the handwheel (tem 1), lower the stem (tem 2) so that the seal retaner assembly Doc. No. A Rev. 2/17

5 Mantenance Instructons (cont.) (tem 3) s below the sealng area of the body (seat). 6. Rest the end porton of the stem on a wood block leveled wth the body, makng sure there s only about 2"- 3" between the body and wood block. Drft out the retanng pn usng a standard 1 /8" dameter drft. Then unscrew the retaner slotted nut, remove retaner assembly, retaner O-rng, and retaner seal washer. 7. To take the Teflon seat seal (tem 10) out of the gasket retaner, put the part nto a vse, wth lght pressure so as not to dstort the gasket retaner. It may be necessary to cut the Teflon out. If so, do t carefully, so that the metallc surface below s not damaged. 8. It s possble to repack the valve wthout removng the stem. To replace the valve packng, begn by movng the handwheel nut, washer, nstructon plate and by loosenng the lock nut (tem 21) by puttng a center punch, drft, or blunt screwdrver on the pont or corner of the nut and gently tappng wth a hammer. Once freed up, use a 1-1 /16" open-end wrench to unscrew the packng screw (tem 8.) 9. The packng (tem 12) can now be pulled out of the body wth the standard packng tools. 10. The stem can only be removed through the bottom of the valve. Loosen or remove the packng screw (see step number 8). Use the handwheel to lower the stem as far as t wll go. Grppng on the flats of the stem square wth an open-end wrench or vse grps, contnue to unwnd the stem down. If the stem cannot be taken out the last few threads by hand, t wll be necessary to lghtly grp the bottom of the stem wth vse grps to dsengage t from the body. 11. To remove the valve s seat nsert, start by loosenng the ¼"-20 socket cap screws. Once all cap screws are removed, the seat nsert can now be removed. There s also an O-rng sandwched between the seat nsert and body. Make sure ths s also removed. Inspecton and Replacement of Parts NOTE: Whenever the angle valves are retested, we recommend that new O-rngs be nstalled. The Teflon seat seal, O-rngs and packng should be replaced, f there s any queston about ther servceablty. All replacement parts must be obtaned from Mdland Manufacturng Corp. No re-machnng of any parts s permtted, except where noted heren. By not observng these prohbtons the purchaser assumes full responsblty and lablty for the proper functonng of the valves. 1. Handwheel. Ths part s desgned to fal when the stem s over-torqued. If a spoke s cracked, or broken off, the handwheel must be replaced. 2. Stem. Roll the stem on a flat and true surface. It wll be apparent f the stem s bowed. If you attempt to straghten t, do not grp or deflect t on the ground surface where the packng seal s acheved, n the ½"-20 thread area and below where deformaton of the metal would foul the threads and damage stem straghtness that would make the value noperable. All ncks, burrs, pts, scratches, etc., must be elmnated, or dscard stem. Screw the stem through the ACME thread of the body wth packng screw n place to make sure t moves freely wthout bndng. The retaner nut has to be secured tghtly wth a retaner washer, O-rng and retaner assembly n place; so, If the ½"-20 thread s slghtly galled, chase t wth a ½" - 20 hand de. If thread s strpped, dscard stem. 3. Seal Retaner. The retaner holds the Teflon seat seal and retaner O-rng. Ensure that no ncks, Doc. No. A Rev. 2/17

6 Inspecton and Replacement of Parts (cont.) scratches, burrs are present n retaner O-rng groove. Also make sure that the two ponted projectons are n good shape to bte nto the Teflon seat seal to produce a frm grp on the seat seal. 4. Body. Inspect the part for corrosve degradaton, partcularly n the seat and the seat nsert areas. Clean off these areas to be sure they are free of corroson, contamnaton, pts, scratches, etc., that could form leak paths. The threads are ½"-13 on sde flange. The threads for the seat nsert are ¼"-20 Spralock. If any of the threads are strpped or corroded, dscard the body. 5. Retaner Washer. If ths has been dshed, flatten n a vse. If ncks, scratches, burrs are present n the area where the retaner O-rng comes nto contact wth the washer, dscard retaner washer. 6. Outlet Flange. The surfaces where the O-rngs ft must be free of ncks, scratches, and pts. Smlarly, the 2" NPT must be n good condton. It can be cleaned wth the standard NPT hand tap. However, a thread gage should be used to be sure the thread s not overszed. The standard hand-tght engagement s nches for the 2" thread.the acceptable tolerance s plus or mnus one thread. If ths tolerance s exceeded, a new part must be obtaned. 7. Packng Screw. The thread s ¼"-12. It must be clean and sharp wthout ncks, scratches, pts, and other defects that would strp or gall the thread when screwed nto the body. 8. Seat Seal. If the Teflon seat s deformed by the seat nsert to a depth of 1 /16", or f t has embedded debrs, dscard t. Replace t wth a new seat from the factory. Ths part s custom made for use on Mdland valves only, and must be purchased from Mdland. 9. Seat Insert. The seat surface s very crtcal and must be examned carefully. The crown of the seat has a full radus (about 1 /16"). Run your fnger nal around the crown to be sure t s free of any ncks, scratches or pts. Also, any chatter or toolmarks on the crown can act as leak paths. The overall heght of the seat crown should not be less than 7 /32". If the condton s questonable, do not take a chance on t replace t wth a new part. The remander of the parts are O-rngs, packng, gaskets, bolts, several types of nuts, lock washers, pns, etc. These are nexpensve parts and to nsure that the rght szes, hardnesses, strengths, materals, and correctly dmensoned parts are used, these replacement parts should be obtaned from the factory. Cleanng NOTE: In preparaton for reassembly, all metallc parts should be steam cleaned. Do not use solvents or grease lubrcants that are ncompatble wth the products n the tank. For example, a petroleum-based grease may cause an mmedate chemcal reacton and fre when t comes n contact wth chlorne. Contact your supervsng engneer for sutable cleanng and lubrcatng materal recommendatons. O-rngs, and other metallc parts that ft together should be lghtly greased. Valve Reassembly 1. Place the lower (flat) packng washer (tem 9) n the body (tem 4). 2. Put the sprng (tem 5) n the body. 3. Install the upper (curved) packng washer (tem 10) n the body, wth the convex sde up. 4. Insert 5 Teflon V-rngs (tem 12) n the body. Doc. No. A Rev. 2/17

7 Valve Reassembly (cont.) 5. Insert the stem seal (tem 13) n the packng screw (tem 8). 6. Thread the packng screw nto the body by pushng down aganst the sprng and turnng clockwse to engage the thread. Wrench tghten a couple of turns. 7. Screw down the packng lock nut (tem 21) a couple of threads on the packng screw. 8. From the bottom sde of the body, nsert the handwheel end of the stem (tem 2). Screw the stem up untl the handwheel flats clear the top of the packng screw. 9. Put on the handwheel (tem 1), and then the nstructon plate and handwheel lock washer (tem 14). By hand, screw the handwheel nut (tem 15) onto the stem as far as t wll go. 10. Turn the handwheel clockwse to move the stem up nto the neck of the body. It should move easly. After several turns, stop. 11. Insert O-rng n seat, nsert groove and apply grease to hold n place. Poston and algn seat nsert nto body recess and secure wth ¼"-20 socket cap screws (tem 23). Usng a star pattern, tghten screws to about 10 foot-pounds. 12. Turn the valve handwheel counter clockwse to lower the stem all the way down. Insert retaner washer wth flat surface facng down. 13. Apply grease to the area below the retaner washer and thread. Insert retaner O-rng and push up aganst retaner washer. 14. Insert Teflon seat seal nto seal retaner. Press t all the way nto the groove. (Ths wll become the retaner assembly). 15. Insert retaner assembly through bottom at stem beng careful to properly algn t wth O-rng so that the O-rng goes nto place n the retaner O-rng groove. Press retaner assembly all the way aganst retaner washer. 16. Secure retaner assembly n place wth slotted nut. Ths nut must be tghtly secured as t creates a tght seal of the retaner O-rng and seat seal. Once tghtly secured and n place, nsert retanng pn (tem 28) and press t all the way n. 17. Usng the handwheel, close the valve by rotatng t clockwse. NOTE: Extra care must be exercsed when handlng, mountng and unmountng valve as the stem extends out of the body. Any damage to the stem wll make the valve noperable wth matng check valve. The stem must be protected at all tmes. 18. Whle makng sure the packng lock nut remans loose, tghten packng screw to 65 foot-pounds to seat the Teflon packng rngs. Then loosen the packng screw about ¼ - ½ turn. 19. Usng the handwheel, open and close the valve to check for nterferences. Then, tghten packng lock nut to 65 foot-pounds 20. Stretch the outlet O-rngs (tem 17 & 18) onto the outlet flange (tem 7). Do not twst the O-rngs. Push ths assembly nto the sde port of the body. 21. Screw n the flange bolts wth Locktte on threads (tem 19) and hand tght, and then wrench-tghten the bolts usng the alternate tghtenng pattern. Do not exceed 45 footpounds. Check for unform spacng between the two flange faces. Correct by loosenng and retghtenng. 22. Whle holdng the handwheel n place, wrenchtghten the handwheel nut. 23. The valve s now ready for test. Doc. No. A Rev. 2/17

8 Testng 1. Bolt the valve to a test fxture n the closed poston. 2. After the valve s secured to the test fxture, close the valve. It should only be necessary to torque the handwheel about 20 to 30 foot-pounds to acheve a bubble tght seal aganst a 500-ps ar supply to the valve. 3. The 500-ps value stated n ths manual, and on the valve nameplate, ndcates the capablty of the Mdland A-728 Angle Valve, and the pressure at whch the valve s tested at the factory. Valves must be tested at a pressure approprate for the applcaton. Typcal practce n the valve ndustry (usng ASME B16.34 as a gude) s to test the body at 1.5 tmes the maxmum workng pressure (wth water or ar), and test the seat at 1.1 tmes maxmum workng pressure (wth ar). Ths apples to the Mdland A-728 Angle Valve wth the caveat that ether test pressure should not exceed 500 psg. Mdland s recommendaton s to test the A-728 Valve at the above condtons and record those values on a test report, f applcable, and on a tag affxed to the valve whch also ndcates the organzaton performng the test. [Note: If the body and seat are tested at 500 psg, the test pressures on the supplemental tag are not requred.] 4. There are several acceptable methods of checkng for a seat leak, but one smple way s to put peces of wde maskng tape across the sde port. Put a small hole n the center of the tape and cover the hole wth a lttle soap suds soluton. Any leak wll then result n a bubble formng at the hole. 5. After the seat has been satsfactorly tested for leakage, thread the ppe plug nto the sde port. Open the handwheel to pressurze the body cavty, and nspect for leaks around the ppe plug and the outlet flange wth soap suds. 6. Then wth soap suds, check the packng gland area for leaks. If any packng leaks are notced, wrench the packng screw down slowly untl the leak stops. Then turn another ¼ turn and lower the lock nut on the packng screw. Snce ths part s only used to keep the packng screw from unwndng when the stem s beng opened, t s not necessary to torque t down beyond snuggng t up by tappng on the corners of the nuts. Post Test Procedures 1. After satsfactorly testng the valve, close the pressure nlet valve nto the test stand, releve the pressure, and demount the valve from the test fxture. 2. Dran whatever water may have accumulated, and wpe or blow away wth an ar hose any soap suds and water used n the testng. 3. Close the valve usng handwheel untl the retaner assembly contacts the seat nsert. 4. Put an approprate preservatve or pant on the exteror of the valve, beng sure to mask the nameplate so t wll be readable afterward. 5. Fll n the test date nformaton on the tag on the valve and store the valve n a dry place untl ready to use. NOTICES AND WARRANTY Mdland Angle Valves are used n a varety of products, many of whch are hazardous materals. The acceptance and transportaton of the products are regulated by the DOT and AAR n the U.S.A., and n Canada by Transport Canada, as well as other governmental bodes, partcularly when used n statonary applcatons. All personnel should be famlar wth and follow these regulatons. Nothng n ths pamphlet s ntended to conflct wth or supersede these regulatons. Doc. No. A Rev. 2/17

9 Obtanng Product Drawngs Assembly drawngs of Mdland Angle Valves are avalable at no charge, and wll be maled upon request. Address any questons concernng valve mantenance or usage to the Engneerng Dept., Mdland Manufacturng Corp. Warranty Mdland warrants the products of ts own manufacture to be free of defects n materal and workmanshp for a perod of one (1) year from the date of nvoce. Furnshed materals and accessores purchased from other manufacturers are warranted only by and to the extent of those manufacturers warrantes, f any. MIDLAND MAKES NO WARRANTY OF ANY KIND WHATSOEVER, EXPRESS OR IMPLIED, OTHER THAN AS SPECIFICALLY STATED HERE. MIDLAND MAKES NO WARRANTIES OF MERCHANTABILITY OR FITNESS FOR ANY PARTICULAR PURPOSE OR USE. Mdland s oblgaton under ths warranty s strctly lmted, at ts opton, to 1) repar or replacement at ts factory of a lke quantty of product: 2) refundng to purchaser money pad to Mdland for ts product: or 3) ssuance of wrtten authorzaton for the Purchaser to repar or replace, at costs comparable to Mdland s normal manufacturng costs those parts proven defectve, provded that Purchaser has gven to Mdland mmedate notce upon dscovery of such defect Merchandse clamed to be defectve shall not be returned wthout frst obtanng Mdland s wrtten consent. The undertakng of repar or replacement by the Purchaser, or ts agents, wthout Mdland s wrtten consent, shall vod Mdland s warranty and releve Mdland of all responsblty. Under no crcumstances shall Mdland be lable for any drect, ncdental, consequental or other damages of any knd n connecton wth the nstallaton, operaton, mantenance, repar, nspecton or other use of any product purchased from t Gross Pont Road, Skoke, IL Phone: (847) , Fax: (847) Doc. No. A Rev. 2/17