Fluke 6270A Service Manual page 71

See Figure 38 for examples of what to inspect for.
•
 make sure there is a good valve indentation on the body surface
where it has made continuous contacted with the orifice.
•
 look for specks on the surface of the indentation. This can cause the
valve to leak.
•
 if tape is in the valve base, the tape could cause intermittent leaks or
control issues.
•
 if tape is in the valve body spring, this tape causes control issues and
leads to leaks if it obstructs the orifice and valve surface.
Figure 38. Inspection
Pressure Controller/Calibrator
PCM Assembly
hxn406.eps
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