Australian Pipeline Valve - Installation, Operation and Maintenance Manual
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 stem shaft area (25A), 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.
The pressure trapped in the body cavity can be vented to the atmosphere while pressure, is maintained in
the pipeline, both in the fully open and fully closed positions.
This characteristic is used to:
1. Ensure that the seats are providing an effective seal.
2. Drain or flush the body cavity of an in-service ball valve.
8.5.1 Venting Procedure
1. Operate the valve to fully open or fully closed position, whichever is more convenient for you.
2. Turn loose the head of the vent fitting (where fitted) (39) located at the top of the body, to release
cavity pressure.
Use extreme caution when venting the body cavity of a pressurised valve.
Continue venting until body cavity pressure is atmospheric. It will take some time to depressurise the
body cavity. It depends on the size of the fitting, body cavity pressure and field compressibility.
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SIDE ENTRY 3P TRUNNION BALL VALVES API6D STANDARD - BVF100 SERIES
