8-3. Assembling the Parts of the Gland
8-3-1. Preparation for Assembly
(1) Checking the surface condition of the parts
Any flaw or the like on the surface of the parts may cause leakage from that area, and
the specified seal performance may not be achieved. Therefore, check the surface of the
following parts.
Table 8-1. Parts to be checked for surface condition
Part name Checkpoints Possible problems
Stem
•
No flaws or defects, including
scratches and dents
•
No rust or corrosion
•
The entire surface is even.
•
No burrs
•
Clean surface, with no adhering
coating material, powder, or dirt.
•
If necessary, take necessary
measures such as cleaning with
alcohol.
Any flaw, rust, corrosion, burrs, dirt,
etc., may cause leakage from that
area, and the specified seal perfor-
mance may not be achieved.
Stuffing box
Both ends of the spacer
Packing follower
Packing contact surface
O-ring groove
Packing flange
Gland nut contact surface
Any flaw, rust, corrosion, burrs, dirt,
etc., may cause insufficient tighten-
ing, and the specified seal perfor-
mance may not be achieved.
Packing flange
Entire surface
Gland stud bolt
Gland nut
•
No flaws, rust, or defects Any flaw, rust, defect, etc., may cause
control valve damage, leading to
injuries.
(2) New parts
When assembling or reassembling, for the parts indicated in the table below, be sure to use
new parts.
Table 8-2. Parts requiring replacement
Part name Checkpoints Possible problems
Gland packing No flaws. No coating materials or
dirt stuck to the surface.
Any flaw, coating material, dirt, etc.,
may cause leakage from that area,
and the specified seal performance
may not be achieved.
Belleville spring Any flaw, coating material, dirt, etc.,
may cause insufficient tightening
and leakage from the gland in a short
period of time, and the specified seal
performance may not be achieved.
(3) Lubricating grease and anti-seizing agent
Have an appropriate amount of the following lubricating grease and anti-seizing agent (or
equivalent) on hand.
Table 8-3. Lubricating grease and anti-seizing agent
Product name Applied area
G40M silicone grease, made by Shin-Etsu Chemical Co., Ltd. Entire surface of the gland packing
Plastilube No. 3 non-dripping grease, made by Sulflo Inc. Entire surface of the backup O-rings
Never-Seez anti-seizing agent, made by Bostik Inc. Threads of the gland stud bolts
Bottom of the gland nuts
8-2
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