SIDE ENTRY 2P TRUNNION BALL VALVES API6D STANDARD - FS9000 SERIES
Australian Pipeline Valve - Installation, Operation and Maintenance Manual
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Sealant injection is a temporary measure, remove the valve at first opportunity and
repair. Greasing the seats can then attach more debris onto the seats so only grease
in an emergency unless flushing with light grease as detailed in section 2.4.
In most cases, sealant injection in the upstream seat will be enough to stop a small leakage. However, it
would probably be necessary to inject sealant each time the valve is operated to keep leakage under
control. If standard grease does not work there are many PTFE composite greases with advanced sealing
capabilities available.
The procedure for injection of sealant in the seats is as follows:
1. Before injection of sealant, ensure that the ball stops are not out of alignment. A small misalignment of
2 or 3 degrees may open the bore hole to the line pressure, causing continuous leakage.
2. Use an appropriate high pressure sealant-injection pump, capable of overcoming the pipe pressure and
the high pressure build-up caused by the sealant itself, during it’s injection in the sealant passages.
3. Confirm that the ball is in the closed position (unless, as is sometimes the case with valves 80NB (3”)
and under, the valve has a single sealant nipple only on body cavity, then it must be in full open
position, see 8.4.1 paragraph 2. Otherwise, the grease will go down the pipeline and the whole
procedure will not be effective.
When removing the safety cap of the grease fitting, be careful not to unscrew the
complete grease fitting out of the body, because it is under pipe pressure. Use a
back-up wrench.
4. Remove the safety cap of the grease fitting.
5. Start injecting a light grade sealant. If you do not succeed, gradually work up to heavier sealants.
6. Recommended quantity is 29 cc (1 oz) of sealant per inch of valve size per seat ring, without
considering the quantity required to fill pump and hoses.
7. Inject only enough sealant to stop the leakage. An excess of sealant is wasteful, and contaminates the
installation downstream.
APV ball valves optionally feature another sealant injection point in the shaft area (see Appendix 3), to
help stop leakage through the O-rings located there. The quantity of sealant required is proportional to
the diameter of the shaft (much smaller than the amount required in the seats).
8.5 DOUBLE BLOCK-AND-BLEED
Whilst trunnion ball valves are double block & bleed capable, the valve needs to be ordered and tested
as a double block & bleed valve and fitted with a drain valve. A special drain ball valve should be
specifically fitted to the lower drain plug.