their share of the load and that anchors are tight. Examine paint for cracking, chalking, or other deterioration.
Remove corrosion by wire brushing, sandblasting, or other acceptable method and repaint.
Pipe and Fittings - Interior Surface
Not Scheduled. Partially disassemble piping or utilize a nondestructive test method to determine condition of
interior surfaces. Measure pipe wall thickness and compare to original thickness.
21. Gate Valves, Globe Valves, Plug Valves, etc.
Annual. Check valve stem packing for leaks and tighten packing gland as required. Operate valve through
its full range of movement several times. With valve closed under pressure, listen for leakage past valve and
correct as required. Lubricate valve stems, plug valve seats, and other components as required with
Not Scheduled. Disassemble valve and inspect condition of valve body, stem, and sealing surfaces and repair
as required. Completely remove old valve stem packing and install new packing.
22. Check Valves
Not Scheduled. Check for leakage past valve while under full operating pressure. Disassemble and replace
or regrind valve seats as required.
23. Pressure Regulating and Pressure Relief Valves
Annual. Check operation and setting of pressure regulating and pressure relief valves.
Not Scheduled. Disassemble valves and remove any scale buildup that interferes with the operation of the
valve. Reassemble and check operation and settings of valves.
Periodic maintenance of a governor is essential for reliability and to maintain optimum performance. When
preparing a maintenance schedule for a mechanical governor, consult FIST,
Volume 2-3, Mechanical
Governors for Hydroelectric Units
and the governor manufacturer's literature.
4.2 Inspection Checklist
1. Governor tests and adjustments
2. Governor ball head
(woodward vibrator type)