Seat Ring Replacement; Assembly Tools - GE Baker Hughes Masoneilan 31000 Series Instruction Manual

B. Valve open on air failure (Air to close) (Figure 8)
a. When the lever has reached the position
corresponding to the required tightness, measure
the "D" distance from the contact surface of the
spring barrel on the yoke to the beginning of the
hole for the clevis pin in the lever (135).
b. Supply air to the actuator so that the actuator
stem moves out fully. Set the clevis (100) so that
the distance from the beginning of the hole for the
clevis pin to the contact surface for the yoke is 1
to 2 mm greater than the previously measured "D"
distance.
c. Remove the handwheel or setting tool and secure
the spring barrel with screws (101) and washers
(102).
2. Move the actuator to an intermediate position, align the lever
and the clevis holes, insert the clevis pin (124) and fit the
clevis pin clips (122).
3. Tighten the locknut (111A).
4. Press the lever (135) against the shaft bearing (125) and
tighten the lever cap screw (137).
5. Secure the indicator (154), screw in the handwheel (141) if
necessary and install the washer (139) and truarc ring (138).
Lock handwheel in neutral position. Install the remaining
covers (118, 121, 130 and 133).
7.4 Eliminating Seat Leakage During Operation
If leakage between seat and plug is found during operation,
it can be eliminated in most cases by adjusting the actuator.
Supply air to put the valve at mid travel, remove the clevis pin
(124) and slide the lever (135) out of the clevis (100).
A. If the valve is closed on air failure (Air to open)
After loosening the locknut (111A), screw the clevis (100) in by
one full revolution.
B. If the valve is open on air failure (Air to close)
After loosening the locknut (111A), screw the clevis (100) out
by one full revolution.
After refitting the clevis pin, check the tightness between seat
and plug. If the necessary tightness has not been reached,
repeat Step A or B as required.
If adequate tightness cannot be achieved by adjusting the
actuator, the seat and plug should be checked for wear.
Tightness between seat and body must also be checked.
© 2017 Baker Hughes, a GE company. All rights reserved.

8. Seat Ring Replacement

To check the seat and plug for wear or to replace the seat ring,
perform the following steps:
1. Bring the plug into its fully open position (if the valve is
closed on air failure, supply air to the actuator to fully open
the plug).
2. Remove the bonnet bolting (14, 15, 16), turn the bonnet
(2) clockwise up to the stop on the body flange, and in this
position, carefully remove it from the body.
The seat ring (4) and plug (3) can now be checked for wear
and the seat ring replaced if necessary. The procedures for
disassembly and reassembly were described in detail in
Sections 6 & 7.
The plug can be replaced only after the complete valve body
S/A has been disassembled. Refer to Section 6.2.

9. Assembly Tools

The operation of fitting the packing and adjusting the actuator
require the use of special tools. In addition these tools reduce
the risk of sealing elements being damaged during assembly.
The tools can be obtained as a complete set from BHGE parts
department and are suitable for all valve sizes (refer to Figure
2).
Fitting tools for the seat rings are available in accordance with
the valve size (refer to Figure 3).
Masoneilan 31000 Series Control Valve Instruction Manual | 8