Masoneilan 75000 Series Tank Mount Control Valve Instruction Manual | 2
Copyright 2021 Baker Hughes Company. All rights reserved.
5mm
Flange
Thread
Body
Set screw (28)
Flat cut
Indications
1. Reinstall the seat ring (12) followed by the plug (13) from the
bottom of the body (10).
2. Install the packing (6), pushing it along the stem portion of the
plug (13).
When installing the packing, be sure to rotate the cut end 180
degrees from the previous piece and push them into position
with the packing follower (4).
3. When the body is reassembled, install the actuator.
4. Tentatively hand-tighten the seat ring (12) to the body (10).
Apply an air pressure lower than the supply pressure to the
bottom of the actuator piston to set the valve to a closed
position, and carefully seat the plug on the seating surface of
the seat ring.
5. Reinstall the nuts(27) to a position where it does not interfere
with the assembly of the split clamp (18). Connect the piston
rod (19) and plug (13) with the split clamp(18). The flat cut on
the plug stem should face the frontside of the split clamp. (The
engagement length of both the threads should roughly be the
same) Make sure the threads of the piston rod and the plug
perfectly engage with those of the split clamp. When they are
perfectly engaged, lightly tighten the nut (16) or the bolt (26) of
the split clamp.
6. Pressurize the top of the actuator piston so that the plug
(13) is lowered away from the seat. Turn the plug (13) 180
degrees clockwise (move the plug up toward the actuator) to
obtain an adequate seating clearance. After turning the plug,
the flat cut on the plug stem should face the backside of the
split clamp (the same side as the thread for the set screw).
Use the 3 indications on the stem as a reference on where
the flat cut is. The value recorded in disassembly would be
of help. Fully tighten the split clamp (18), with the following
torque:
M 1 2（# 1 2）：2 5 ～ 3 0 N・m 、M 1 6（# 1 6 - 2 8 A）：5 5 ～ 7 0 N・m
UNC3/4（#32）：285～340N・m
Lock the 2 nuts (27) together by using proper tools. The nut
should not touch the bottom of the split clamp.
Screw in a set screw (28) against the flat cut of the plug stem
as a prevention for rotation. Screw in a second set screw
(28) to keep the first one from loosening.
Connect the positioner linkage to the split clamp.
7. Install the valve to the piping, referring to the procedure for
installation.
8. Connect all the air tubings.
Reassembly is now completed. Prior to operation, be sure to
check for the valve action, openings, etc.
Polishing the Valve Seat
Periodically conduct a maintenance check of the packing box.
The sealing performance of the packing is maintained by
compressing the packing.
Compression is obtained by evenly tightening the packing
flange stud nut (2) for the packing flange(3).
But please be aware that tightening the packing flange too
much may result in stiff actuation. If the leak does not stop after
complete compression, new packings are necessary.
When assembling the split clamp to the plug stem
and piston rod, follow the instructions below.
a) Before assembly, confirm the threads are free of any
foreign objects. If there are any objects, remove it
by cleaning and airblowing the threads.
b) Do not use any lubricants on the threads of the stems.
c) If there are any brackets for accessories mounted
on the split clamp, the split clamp must first be
securely assembled before mounting the brackets.
Figure 1 - Threaded type flange
Figure 2 - Anti-rotation measure with single lock nut
Figure 3 - Indications on the plug stem
Flat cut
Indications
