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Baker Hughes
© 2020 Baker Hughes Company. All rights reserved.
E. Spindle Runout
It is important that the spindle be kept very straight in
order to transmit the spring force to the disc without
lateral binding. Overgagging is one of the common
causes of bent spindles. A method to check the
essential working surfaces of the spindle is illustrated in
Figure 8 below.
Using a spindle check stand (see Figure 8 as a
reference), place the ball end of the spindle into a
depression at the base “B” of the stand. Lean the upper
portion of the spindle against the “V” block. It should be
touching the spindle just below the threads on the upper
portion of the spindle. Using a machinists indicator on
a 45° angle at spindle shoulder "C", rotate the spindle
and read the Total Indicator Run out on the indicator.
If the TIR is less than values shown in Table 1, the
spindle may be returned to service. If the TIR is greater
than these values, straighten the spindle using "V"
blocks and a hydraulic press until the TIR is found to be
acceptable.
Other parts of the spindle not used as working
surfaces may run out considerably more than .007”
(0.18 mm), but this should not be regarded as
unacceptable. Although the upper thread end is not a
working surface, excessive bending in this area could
effect the accuracy of the Consolidated Hydroset
device, and/or the Consolidated Electronic Valve
Tester (
EVT
™), if either of these devices is used to
verify valve set pressure.
F. Spring and Spring Washers
Spring wire that is irregularly spaced, or the ends are
not parallel, are sufficient causes for replacement. The
spring washers are machined to fit the ends of the
spring - there should be no more than a .030” (0.76
mm) clearance between the spring and the spring
washer. If a spring is badly damaged by corrosion
(flaking, pitting, or reduction in wire diameter), replace
the spring with the proper spring. If the spring is
unable to be identified contact the Baker Hughes Field
Service Department.
A
C
45
0
A
B
Figure 8
Spindle Check Stand
XI. Maintenance Instructions (Cont.)
Table 1:
Spindle Critical Dimensions
Orifice
C max
in.
mm
H
.004
0.10
H
.004
0.10
H
.004
0.10
J
.004
0.10
K
.007
0.18
L
.007
0.18
M
.007
0.18
N
.007
0.18
P
.007
0.18
Q
.007
0.18
