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Baker Hughes
© 2020 Baker Hughes Company. All rights reserved.
1. When (E) dimension is reduced to .020” (0.51 mm) for H – N orifices, or .025” (0.64mm) for P – Q orifices,
restore the dimensions to those indicated in Table 8b. Seat Bushing is re-machinable until minimum (G)
dimension is reached, then must be discard.
Table 8b: Seat Bushing Rework/Inspection Dimensions
Orifice
B max
C
E
(1)
F
in.
mm
in.
mm
in.
mm
in.
mm
H
1.182
30.02
1.304
+
-
.000
.003
33.12
+
-
0.00
0.08
.028
+
-
.002
.003
0.71
+
-
0.05
0.08
.079
+
-
.002
.003
2.01
+
-
0.05
0.08
J
1.513
38.43
1.635
+
-
.000
.003
41.53
+
-
0.00
0.08
.025
+
-
.005
.000
0.64
+
-
0.13
0.00
.098
+
-
.005
.000
2.49
+
-
0.13
0.00
K
1.809
45.95
1.931
+
-
.000
.003
49.05
+
-
0.00
0.08
.025
+
-
.005
.000
0.64
+
-
0.13
0.00
.117
+
-
.005
.000
2.97
+
-
0.13
0.00
L
2.248
57.10
2.400
+
-
.000
.003
60.96
+
-
0.00
0.08
.028
+
-
.002
.003
0.71
+
-
0.05
0.08
.149
+
-
.002
.003
3.78
+
-
0.05
0.08
M
2.523
64.08
2.676
+
-
.000
.003
67.97
+
-
0.00
0.08
.028
+
-
.002
.003
0.71
+
-
0.05
0.08
.167
+
-
.002
.003
4.24
+
-
0.05
0.08
N
2.773
70.43
2.950
+
-
.006
.000
74.93
+
-
0.15
0.00
.025
+
-
.005
.000
0.64
+
-
0.13
0.00
.179
+
-
.005
.000
4.55
+
-
0.13
0.00
P
3.364
85.45
3.547
+
-
.000
.004
90.09
+
-
0.00
0.10
.036
+
-
.005
.000
0.91
+
-
0.13
0.00
.217
+
-
.005
.000
5.51
+
-
0.13
0.00
Q
4.424
112.37
4.615
+
-
.000
.003
117.22
+
-
0.00
0.08
.036
+
-
.005
.000
0.91
+
-
0.13
0.00
.285
+
-
.005
.000
7.24
+
-
0.13
0.00
During reassembly, three items are of extreme
importance. They are:
1) Alignment
2) Cleanliness
3) Lubrication
To achieve the correct alignment, the bearing surfaces
of the compression screw/upper spring washer, spindle/
lower spring washer and spindle to disc pocket should
each be ground together to attain a perfect match. This
is done by applying a lapping and grinding compound
of about 500 grit on one of the surfaces and rubbing the
surfaces together until a smooth unbroken contact point
is established on both surfaces.
All bearing surfaces and threaded areas must be
lubricated using a high quality high temperature lubricant.
At the factory, Nickel-Ease
®
is used and is recommended.
For environments where corrosion is a problem, contact
the factory field service department for suggestions on
special coating or plating procedures which will protect the
parts.
1. Thread the lower ring onto the seat bushing and
turn it down until it is below the seating surface.
(This allows the disc to rest on the bushing without
interference from the ring).
2. Thread the upper ring/guide into the valve body
reestablishing its original relationship to the bushing,
as measured in Section X, Disassembly of 1511
Series Safety Valve, step 2. Insert the upper
adjusting ring pin into the valve and tighten. The ring
should now be able to rock back and forth but not
turn. If position is not known, refer to Section XIV.C.
3. After inspecting both the disc and bushing seat for
cleanliness, thread the spindle into the disc and
insert the disc gently into the valve until it rests on the
bushing.
4. Place the spring and spring washers onto the
spindle.
5. Place the yoke over the spindle and replace the
cap screws or nuts. Care must be taken to tighten
the yoke down evenly to prevent distortion and
misalignment.
XIII. Reassembly
XII. Inspection and Part Replacement (Cont’d)
