Iv. rebuilding, Worcester controls – Flowserve Cryogenic Ball Valves User Manual

Page 3

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08164-S

3

Flow Control Division

Worcester Controls

CAUTION: The self-locking stem nut is difficult to tighten and must
fully flatten the Belleville washers before backing off.

4. If seepage is noted at stem on 3"–6" valves, tighten retaining

nut

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6

-turn at a time until seepage stops.

IV. REBUILDING

THIS MANUAL CONTAINS EXPLODED VIEWS OF ALL VALVES
COVERED BY THE TEXT. THEY HAVE BEEN INCLUDED TO AID IN THE
REBUILDING OF THE VALVE. PLEASE REFER TO THEM WHEN
FOLLOWING THE WRITTEN INSTRUCTIONS.

a

WARNING: BALL VALVES CAN TRAP PRESSURIZED FLUIDS IN

BALL CAVITY WHEN CLOSED. If the valve has been used to control
hazardous media, it must be decontaminated before disassembly.
It is recommended that the following steps are taken for safe
removal and disassembly:

Relieve the line pressure. Operate the valve prior to attempting
removal from line.

Place valve in half-open position and flush the line to remove
any hazardous material from valve.

All persons involved in the removal and disassembly of the
valve should wear proper protective clothing such as face
shield, gloves, apron, etc.

A. A standard repair kit can be ordered for the Worcester Cryogenic

Valve containing all necessary parts for normal valve rebuilding.
To order a repair kit you must specify the size, type of valve
(extension or no extension), “RK44” and revision (“C” or “R” and
number). This information is found on the valve body, stop plate,
handle, valve nameplate, or mounting bracket nameplate.

Example:

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" CN RK44 R6 (The “N” indicates there is no

extension) or 3" C RK44 R12.

If the valve is a non-standard product, then there is a five-
character code called a “P”, “T”, “C”, or similar number, found on
the valve body, stop plate, handle, valve nameplate, or mounting
bracket nameplate. To order repair kit, include size, type of valve,
“RK44”, and “P”, “T”, “C”, or similar number.

Example:

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" CRK44 P2577 or

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" CNRK44 TO726

CAUTION: If the seats and seals installed differ from those
removed, the valve nameplate or stop must be replaced or
remarked to indicate the altered materials and ratings, or the
valve must be tagged to so indicate.

B. If replacement parts other than those included in the repair kit are

needed, order the part by name and size, including the complete
valve code. For non-standard product add “P”, “T”, “C”, or similar
number, see valve body, stop plate, handle, valve nameplate, or
mounting bracket nameplate for this information.

Example: Ball,

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" C416 PM SE R3 or

Ball,

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" CN466 PM SE TO914

Porting (if diverter cryogenic valve) must also be specified when
ordering these parts – Example: Ball; 1" C416 PM SE V1 R6.

To Replace the Seats and Seals in

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"–2" Cryogenic Valves:

NOTE: If stem seal replacement is not required, omit Steps 5, 6, 7, 10,
11, and 12.

C. 1. Open

valve.

2. Remove three body bolts and loosen the fourth and swing the

center section out from between pipe ends or remove all four
bolts and remove valve from line, whichever is more
convenient.

3. Close

valve.

4. Remove the ball, seats and body seals. Discard seats and

body seals.

5. If present, remove handle nut, lockwasher, handle and stop

plate. Remove retaining nut or self-locking stem nut, Belleville
washers and stem seal follower(s). On valves with a handle
and stop plate assembly, first loosen handle socket head cap
screw, then remove handle nut and proceed with disassembly.

Valves Without Extension

6. Push stem into the body cavity and remove thrust bearing(s)

from stem, then remove the stem seals and stem seal
protector (if any) from body.

Valves with Extended Bonnet:

7. a. Push stem into body cavity.

b. Remove pin from stem.

c. Unscrew bottom tang of stem from stem extension

(right-hand thread).

d. Remove thrust bearing from stem bottom tang.

e. Push stem extension out of body.

f. Remove fluoropolymer stem seal and metal seal washer

(follower).

Follow Steps 8, 9 & 10 for Both Extended and Non-Extended Valves:

8. Clean all sealing surfaces of valve including the ball.

9. Inspect the ball and the surfaces against which the seats and

seals are installed, they should be undamaged, clean and free
of pit marks and scratches. Light marring from the action of
the ball against the seats is normal and will not affect the
operation of the valve. Flaws which can be seen but barely
detected with finger tips are acceptable. The stem and body

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