Australian Pipeline Valve - Installation, Operation and Maintenance Manual
19
LUBRICATED PLUG VALVES - SAPM/SAPL
4.2.3 Adjustment of gland
The gland has two functions, to effect a seal on the stem and also to give a plug loading into the body.
The gland should always be reasonably tight to give correct resistance for the sealant system - if the
gland is loose then the sealant film will not properly form between the seats. Over a period of time -
particularly if the valve is subject to elevated or cyclic temperature fluctuations - the gland will need to
be tightened.
Using a wrench, tighten with reasonable hand force. Take care not to over tighten or the plug will not
turn. Once the gland has been tightened, sealant should always be injected and the valve operated to
check that the valve is working correctly.
5 . 0 R E P A I R
Only minor repair should be attempted. Major repairs should be undergone by an APV approved plug
valve specialist repairer. This is a general guide.
5.1 DISASSEMBLY
During disassembly care must be taken to avoid damage to individual component surfaces. Similar care
should be taken with gasket contact areas of flanges. For drawing refer to our as-built drawing for each
item supplied with order. The below procedure is a general guide, parts vary according to size & class.
Disassembly should be performed by an APV approved service centre. Refer Appendix A, B & C as a guide
but consult the as-built drawing as designs vary according to size, class & style.
1. Remove the valve from pipeline with plug in the OPEN position. Before removing valve bleed off
residual pressure that may be in the body cavity.
2. Remove valve operator (gearbox or wrench).
5.2 INSPECTION & REPAIR
1. Degrease and clean all components of the valve. Particular attention should be paid to the cleanliness
of the sealant grooves in the plug.
2. Clean and degrease the upper and lower chambers in the body and visually check for signs of damage
or wear.
3. Visually examine the plug surfaces and the contacting surfaces of the valve body for damage or wear.
4. There should be no deformation or wear on cover.
5. Replace any worn or damaged parts such as: O-rings, thrust bearing, diaphragm, etc.
