Instruction manual

A31A Valve
Instruction Manual
Form 5291
March 2008
8
Figure 4. Proper Installation Steps
B2263-1/IL
A5557/IL
Figure 5. Properly Installed Wafer-Style Valve
Adjusting the Actuator Travel Stops or
Travel
Key number locations are shown in figure 9, unless
otherwise noted.
1. Refer to the actuator instruction manual to locate
the actuator travel stop that control the closed
position of the valve disc (key 2). When adjusting the
travel stop or travel, make sure that the disc is from
0 to 0.76 mm (0 to 0.030 inch) away from the
internal stop in the valve body (see figure 8). This
adjustment is necessary to be certain that the
actuator output torque is fully absorbed by the
actuator travel stop or by the actuator. The internal
travel stop in the valve body should not absorb any
of the actuator torque.
CAUTION
When using an actuator, the actuator
travel stop (or actuator travel, for
actuators without adjustable stops)
must be adjusted so the disc stop in
the valve does not absorb the output
of the actuator. Failure to limit the
actuator travel as described in the
Adjusting the Actuator Travel Stops or
Travel steps can result in damage to
the valve, shaft(s), or other valve
components.
2. Before installing the valve/actuator assembly in
the process line, cycle the valve several times to be
sure the valve disc returns to the proper position.
Installing the Valve
The maximum allowable inlet pressures for Type
A31A valves are consistent with the applicable
ASME pressure/temperature ratings except where
limited by the material capabilities as shown in
table 2 or figure 3.
Refer to table 5 for the quantity and size of line
bolting required to install the valve in the pipeline.
CAUTION
To avoid damage to the valve disc
during installation, the valve must be
in the fully closed position. If the Type
A31A valve is equipped with a
fail-open actuator, remove the actuator
before installing the valve/actuator
assembly or cycle the valve into the
fully closed position. Then, take
appropriate steps to be sure that the
actuator does not cause the valve to
open during installation.
1. See figure 5 for recommended valve orientation.
D For Wafer-Style Valves: Install the lower
flange bolts first to form a cradle for the valve (see
figure 4). See table 5 for flange bolt specifications.