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Crosby style JCe safety ValVe
InstallatIon, MaIntenance and adjustMent InstructIons
4.3 bellows valve - refer to figure 1
4.3.1 Remove the bellows unit (23) complete
with disc assembly from the seat (4), being
careful not to lose the lift stop (81) and ball
(31). If the valve is a resilient seated model
follow the procedure outlined in 4.2.2. to
remove the resilient seal; this must be done
before the bellows unit (23) is removed.
4.3.2 If the bellows unit (23) requires replacing,
this will be supplied welded to the disc.
the disc will be supplied fully lapped in
protective wrapping. Only use factory
supplied bellows units.
4.4 Marine cap - refer to figure 2
to remove the marine cap (3) first remove
the fulcrum pin (56) from the lever (73) using
a suitable tool as a drift. the lever (73) may
now be withdrawn from the cap (3). slacken
the grub screw (75) and unscrew the marine
cap (3). It is recommended that the spindle
nut (61) should be marked prior to removal so
that the correct position can be attained upon
reassembly. Remove the spindle nut (61) and
the spindle washer (83).
further dismantling of the valve is achieved by
following the procedure outlined in 4.1.
4.5. Packed cap - refer to figure 3
to remove the packed cap (3) first undo the
gland (57). It may be necessary to ease the
eccentric shaft (70) outwards during this
operation to ensure that the gland (57) can
be withdrawn from the cap (3). the lever
assembly may now be withdrawn from
the cap complete with gland packing (58).
the tension pin (35) should be released from
the lever (73) by using a suitable tool as a drift.
the lever (73), gland (57) and gland packing (58)
may now be removed from the eccentric
shaft (70).
note: It will be necessary to fit new gland
packing (58) on reassembly.
the cap (3) may now be unscrewed from the
bonnet (2). It is recommended that the lock
nut (82) should be marked prior to removal so
that the correct position can be attained upon
reassembly. Unscrew the locknut (82) and the
spindle nut (61).
Valve size
1"
1¼"
1½"
2"
2½"
3"
4"
Dn
'a' pin dia x length prior to cut off
'B' pin/drill depth
further dismantling of the valve is achieved by
following the procedure outlined in 4.1.
5 ExaMInatIon anD rEConDItIonIng
5.1 Disc
examination of the disc (5) will reveal whether it
requires re-lapping. the disc may be re-lapped,
using a flat cast iron lapping plate. Using a
fine lapping paste, without applying excessive
pressure, lap the disc until all imperfections
have been removed from the seating face. If
the disc is too badly damaged to relap fit a new
disc.
5.2 seat
examination of the seat (4) will reveal whether it
requires relapping. the seat (4) may be lapped
in situ in the body (1) using the same lapping
plate as for the disc (5) and following the same
procedure. If the seat face is too badly damaged
to re-lap it must be remachined. the maximum
amount of metal it is allowable to remove is
3 mm. If this is exceeded, the valve must be
returned to the factory for a new seat fitting.
Having been machined the seat (4) should be
re-lapped as previously described.
note: ensure all lapping paste is removed from
the seat (4) and the disc (5) before reassembly.
5.2.1 Seat replacement
In the event of complete seat
replacement being required, the existing
seat must be machined out, and an
oversize seat obtained from the factory.
Do not omit removal and replacement of
the seat security pin.
Machine out seat recess diameter to
give interference at ambient conditions
according to the following table.
5.2.2 Procedure for fitting new seat
Remove existing seloc pin. Remove /
machine seat from body. Re-machine
body to dimensions in table above. Coat
body recess with 'Boss White sealant'.
Insert seat into liquid nitrogen and leave
until temperature has been reduced to
minus 196°C. Remove seat from liquid
nitrogen and insert into body recess,
body dimensions (inch)
1.3008 / 1.2992
1.5764 / 1.5748
1.9701 / 1.9685
2.3642 / 2.3622
3.1516 / 3.1496
3.7425 / 3.7401
4.7268 / 4.7244
25
32
ø3 x 18
ø3 x 24
1
1.5
5.2.3 Seat change procedure
seat dimensions (inch)
1.3039 / 1.3029
1.5795 / 1.5785
1.9739 / 1.9729
2.3690 / 2.3678
3.1576 / 3.1564
3.7499 / 3.7485
4.7358 /4.7344
40
50
ø3 x 28
ø3 x 36
2.5
2.5
using tools provided Hammer the seat
into body ensuring that the seat properly
'bottoms' in the recess. allow assembly
to reach room temperature.
Drill into seat 'B' depth as shown below
through existing hole in body, and fit new
'seloc' pin. Cut and dress pin flush with
body. (Note that body will be received
drilled)
Interference (inch)
0.0037 / 0.0021
0.0047 / 0.0021
0.0054 / 0.0028
0.0068 / 0.0036
0.0080 / 0.0048
0.0098 / 0.0060
0.0114 / 0.0076
65
80
ø3 x 36
ø3 x 40
2.5
2
100
ø3 x 45
2.5
2
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