5
50 (2)
3
10
85 (6⅜)
80 (3)
3
10
230 (9)
100 (4)
3
10
260 (10
5
/
16)
150 (6)
4
10
380 (15)
200 (8)
5
10
485 (19⅛)
250 (10
4
10
595 (23½)
300 (12)
4
10
700 (28)
350 (14)
4
15
780 (30⅝)
400 (16)
4
15
890 (35)
450 (18)
4
15
990 (39)
500 (20)
4
15
1095 (43)
600 (24)
4
16
1320 (51⅞)
750 (30)
4
16
1655 (66⅛)
REPACKING INSTRUCTIONS
Tools and materials required
1. Open end wrenches or sockets to fit packing
gland hex nuts and 4-Post yoke hex nuts.
2. Square braided packing suitable for
application - Keystone standard packing is
special PTFE impregnated synthetic (AFPL).
3. Knife, to cut packing.
4. 10 x 50 mm (
1
/
32
x 2") flat bar approximately
50 mm (2") long with rounded end.
5. Tool with radius end to fit inside of packing
box.
TABLE 3 PACKING SIZES
Valve size
DN (NPS)
Number
of rows
Cross
section
Cut length
mm (in.)
KEYSTONE
FIGURE PCS17 KNIFE GATE VALVES
INSTRUCTION, OPERATION AND MAINTENANCE MANUAL
NOTES
1. Important, do not tighten packing gland bolts any
more than required to stop packing gland leaks
after line pressure is applied.
2. Self-mold packing is triangular in shape, 12.7 mm
(½”) (equilateral) on a side and about 63.5 mm
(2
1/2
”) long. It can be broken into pieces to conform
to the shape of the packing box. Install one (or
two) row(s) of self-mold as appropriate for the size
valve. See Figure 8. Make sure that all voids are
filled.
3. High-temperature packing may not reach full
pliability until normal temperature is achieved.
Packing may require readjustment as temperature
changes.
Installation of new packing
If valve is equipped with self-mold packing,
see note 2 before starting.
1. Cut packing to exact length for each row
(Table 3). Starting on either side of the gate
install the packing all-around the gate one
row at a time.
2. Tamp packing into packing box, even and
flat using flat bar or other suitable tool.
3. Add next row, alternating sides of the gate
where the ends of the packing meet against
each other. (Ends of packing must not line
up. If they do premature leakage could
occur.) Complete by adding the number of
rows required. (Figure 8)
Prepare valve
1. Relieve pressure on valve or remove valve.
2. Close the valve.
3. Disconnect the spindle from the gate.
(Figure 7)
4. Raise spindle or rod to the fully raised
(open) position, providing clearance, or if
desired, the entire actuator assembly may
be pulled up and away from valve, see steps
a and b.
a. After step 3, remove top plate hex nuts
and washers from 4-Post yoke.
b. Pull valve spindle and entire actuator
assembly, excluding 4-Post yoke up and
away from valve, set aside.
5. Remove packing gland hex nuts, packing
gland, and old packing.
CAUTION
Follow required safety procedure and policies.
Assure line is not pressurized before loosening
packing and removing valve. Use proper lifting
and support techniques when moving valve and
or valve subassemblies.
4. Reassemble packing gland to valve by
sliding it down gate, aligning bolt holes with
gland studs.
5. Tighten packing gland until the top row of
packing is slightly compressed.
6. Reassemble the actuator assembly, attach
lifter to gate.
7. Slowly charge line, stop when packing
leak is evident or until normal pressure
is reached.
8. Retighten packing gland bolts only enough
to stop the leakage, do not overstress the
bolting.
9. If normal pressure has not been achieved,
continue to add pressure and adjust packing
gland until normal pressure has been
reached.
10. Check gland bolts and snug all packing
gland nuts.
NOTE
Valve with self-mold packing illustrated
FIGURE 8
Gate
Packing gland
Packing
FIGURE 7
Body
