8/19/2019 Butterfly Valve Maintenance - NEW

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Maintenance Instructions

Disassembly

Manufacturing

2825 West Washington

Stephenville, TX 76401800 772 8582

FMC Technologies Inc.

1803 Gears Road

Houston, TX 77067281 260 2121

Maintenance and Repair

Assembly (Ref: FMC Specification3253718 or Q50038)

Installation with Flanges

1. Close valve and remove from the line. Turnthe valve to the open position. Handle maybe left on the upper stem or taken off byremoving cap screw and washer.

2. Remove both the upper and lower roll pins with a drift pin or pin punch and hammer.(Use any strong piece of steel rod whichfits the roll pin hole ID)

3. Pull both the upper and lower stems fromthe body. If the stems cannot be removed

readily, grasp the stem in a vise and gentlytap the body with a hammer. A twistingmotion between the body and stems willallow the stems to be removed easily. Agroove on the lower stem permits pryingthe lower stem from the body by using ascrewdriver.

4. Remove the disc from the seat.

5. Remove the seat from the body. The seatmay have to be tapped lightly and evenlyaround the edge from one end since theseat fits snugly the body ID. Take care notto damage the inside of the body.

1. Inspect the disc and stems. If worn orpitted, substitute new ones.

2. When replacing the seat, new O-ringsshould be installed.

3. It is recommended that all rubber parts(seats, O-rings) be lightly but thoroughlylubricated with a grease such as DowCorning®  #111 silicone, to facilitateassembly. Spread lubricant on the insidediameter of the seat.

1. Place well lubricated O-rings into the topand bottom holes of the seat.

2. Place the seat in a vise with the stem holes

parallel to the vise jaws. Use smooth jawsor otherwise protect the seat OD fromdamage. Carefully apply pressure to distortthe seat and only enough pressure to insertthe disc. Excessive pressure can damage theseat. Slide the disc into the seat and centerthe disc by inserting the upper and lowerstems. Remove the seat/disc subassemblyfrom the vise.

3. Using the upper stem, rotate the disc to thepartially closed position.

4. Remove the upper stem (leaving the lowerstem in place).

5. Lubricate the body ID or seat OD with asilicone spray such as Dow Corning #316.Using lower stem in the seat/disc assemblyand a lower stem in the body, lay the seat/ disc assembly on top of the body using aright angle alignment fixture to align the

stems. Insert the seat enough to get startedand then remove the stems from the bodyand the seat/disc assembly. Completeinserting the seat/disc assembly into thebody with uniform pressure.

6. Install third O-ring in groove of upper stem.If butterfly valve has a grease fitting, skivecut third O-ring prior to installation ontoupper stem. Lubricate upper and lowerstems with Climax 422 CM or equivalent(ref. FMC specification 3259721). Applylubricant on smaller surfaces at disc end ofthe lower stem. Apply lubricant on largeOD surfaces of upper stem, between theO-ring groove and the hex end. Do notapply lubricant in roll pin groove or onsmaller surfaces on hex end.

7. Install the lower stem into the body. Thelower stem is in correct position when theroll pin hole in the body is aligned with thegroove on the stem.

8. Before installing the upper stem, orient theindicator groove on top of the upper stemso that it is aligned with the disc. Installthe upper stem into the body by pushingthe stem while slightly turning back andforth. This will allow the stem to engageand align with the disc hex. The upperstem is in the correct position when theroll pin hole in the body is aligned with thegroove on the stem.

9. Install roll pins into body with start ofoutside of coil 180° away from stem groove.

Make certain roll pins pass through groovesof stems and are flush with body. Apply aclear silicone adhesive sealant to the endsof the roll pins.

10. Install the cap screw and washer to retainthe handle.

11. Install the cap screw and washer to retainthe handle.

12. Install detent plate. Tighten detent platemounting bolts until lock washer isflat. If installing a 180° detent plate, theplate should be installed so the

 valve will have 2 closed positions and 1open position. Countersunk holesof the detent plate should be installed ontop.

13. Hand tighten retaining cap screw and

 washer on the upper stem.

Valves should be in the closed position duringinstallation to prevent damage to the disc. Checkindicator groove on top of upper stem for properdisc alignment. After tightening flanges againstthe valve, valve may be opened, but cautionshould be taken to ensure opening of disc doesnot contact ID of flange or pipe. Striking of disccan result in possible leak paths.

Weco® Butterfly Valve

12

13

3

9

8

11

5

11   10

1

6

7

2

10

11

4

1. Body

2. Disc

3. Upper Stem

4. Lower Stem

5. Seat

6. Detent Plate

7. Cap Screw

8. Lock Washer

9. Hex Nut

10. Roll Pin

11. O-Ring

12. Cap Screw

13. Washer