
SERIES 950 UNIDIRECTIONAL KNIFE GATE VALVE
Installation, Operation and Maintenance Manual
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Figure 15: Bolt holes in the chest or
upper flange area are blind tapped
CAUTION
If the gland nuts are pulled too hard, the force needed to operate the
valve will increase, the valve function will be affected and the box packing
lifetime will be shortened.
8.4 Gland packing is tightened to hold the specified pressure and
tested for no leakage before dispatch. However, this may
require some adjustment at site due to loosening in transit etc.
8.4.1 Tighten packing gland in a crisscross pattern until the packing ring
at the top is slightly compressed.
8.4.2 Pressurize the valve gradually and stop when packing leak is visible
or design pressure is reached.
8.4.3 Re-tighten packing gland bolts just enough to stop the leakage.
8.4.4 If maximum design pressure is not reached, continue to pressurize
the valve and repeat steps 8.6.2 and 8.6.3.
CAUTION
Support should be used for valves size 12"and over when installed in
vertical pipe. Failure to do so can result in improper valve orientation
and/or valve failure.
CAUTION
Care must be taken when installing the studs or bolts in the tapped holes
of the flange in the chest area to prevent damage, see Figure 15 and
Figure 16.
Figure 16: Flange Bolting
Note: To determine bolt length for
the blind holes in the upper chest
area of the valve, add thread
depth+ gasket + flange thickness +
any washers (plus deflection cone
and gasket when used)
Figure 15: Bolt holes in the chest or
upper flange area are blind tapped
CAUTION
Incorrect electrical supply to accessories will damage the equipment. Do
not over tighten the gland nuts as this may cause excessive friction and
premature damage to packing.
Figure 17: Cylinder Actuator
8.5 PNEUMATIC CYLINDER OPERATED VALVES
8.5.1 In Figure 17, connect instrument quality air, preferably through an
air filter/regulator of adequate size.
8.5.2 The recommended air pressure is 50-100 psi (3.5-7 bar). Refer to
the appropriate bulletin/drawing for port and cylinder size details.
8.5.3 Make sure the supply air is free from moisture, dirt, and other
foreign particles.