Flowserve Cryogenic Three-Piece Bodied Extended Bonnet Ball Valve - Manual (Page 2)

2 Cryogenic Three-Piece Bodied Extended Bonnet Ball Valve: Installation, Operation and Maintenance 17646-L
c. “S” type gaskets are installed with their widest flange to
the valve body (See view A-A on pages 5 and 6).
d. Swing center section back in line.
e. Tighten and torque body bolts evenly and diagonally
opposite each other, alternating in a criss-cross pattern.
Use torque figures below:
II. OPERATION:
A. To operate the Worcester Cryogenic Ball Valve turn the stem
1 /
4
turn clockwise to close and 1 /
4
turn counterclockwise to open.
On manually operated 1 /
4
" – 2" valves, the handle and the arrow on
the top stem flat act as pointers. When they point across the
pipeline, the valve is closed. When they point downstream, the
valve is open.
B. To operate the Worcester Cryogenic Diverter Valve, rotate handle
1 /
4
turn to divert the flow from the bottom port to either of the side
ports. The diverter valve comes with a 90° ball and the arrow on
the top stem flat can be disregarded. The diverter valve also
comes with a special 180° ball. In this case the handle would be
rotated
1 /
2
turn and the handle and the arrow on the top stem flat
would point to the port to which flow was diverted.
C. These valves will provide positive shutoff when used in accordance
with the Worcester Cryogenic Valve pressure/temperature chart.
D. DO NOT leave the ball partly open. DO NOT throttle with
Worcester cryogenic valves. It will result in seat breakage.
E. DO NOT allow media that can solidify, crystallize or polymerize to
stand in the valve cavity.
F. Torque Requirements:
The valve torque will vary depending on the length of time
between cycles, line pressure, type of valve seats, and the media
in the system.
All figures in the following table are based on laboratory tests
with LN2 as the media. These figures should approximate the
actual valve torque. For a more detailed analysis of valve torque
requirements, see the Worcester Actuator Sizing Manual.
III. MAINTENANCE:
The Worcester Cryogenic Valve with the extended bonnet normally
operates with the bonnet at a higher temperature than the valve.
Because of this, there will be a frost line about two-thirds of the way
up the extension. If the bonnet should become covered with frost,
that would be an indication that the packing rings were leaking.
If stem leakage is noted then adjust retaining nut per following
procedure:
CAUTION: Excessive tightening causes higher torque and shorter
stem seal life.
A. Packing ring readjustment procedure if possible:
1. Allow the valve to warm to ambient temperature to allow
packing rings to become more flexible.
2. On Rev. R6 and R7 manual valves, loosen the handle nut to
allow easy access to the retaining nut. Loosen top nut on
actuated Rev. R6 valves. Rev. 7 actuated valves have a single
self-locking stem nut.
3. For Rev. R6 manual and actuated, and Rev. 7 manual valves,
while holding the stem to prevent turning, tighten the
retaining or lower nut until Belleville washers are flat (approx.
120 in-lb for
1 /
4
"-1" stems, 130 in-lb for 1 1 /
2
" and 2" stems);
then back off 1 /
6
turn.
For Rev. R7 actuated valves, while holding the stem to
prevent turning, tighten the self-locking stem nut until
Belleville washers are flat, the nut will “bottom”, then back off
nut
1 /
3
turn.
CAUTION: The self-locking stem nut is difficult to tighten,
and must fully flatten Belleville washers before backing off.
4. Retighten the handle nut (Rev. R6 and R7 manual valves) or top
nut (R6 actuated valves) while making certain that the retaining or
lower nut and stem are immobile.
Maximum Expected
Valve Size Breakaway Torque
1 /
4
" – 1 /
2
" 80 in-lb
3 /
4
" 150 in-lb
1" 200 in-lb
1 1 /
2
" 475 in-lb
2” 625 in-lb Bolt Diameter in-lb ft-lb
1 /
4
" 72 – 94 6 – 8
5 /
16
" 120 – 144 10 – 12
3 /
8
" 192 – 216 16 – 18
7 /
16
" 336 – 384 28 – 32
1 /
2
" 504 – 552 42 – 46
Flow Control Division
Worcester Controls