Australian Pipeline Valve - Installation, Operation and Maintenance Manual
13
FLOATING BALL VALVES - BV100 SERIES
If a gasket seal is disturbed while removing or adjusting gasketed parts, APV
recommends installing a new gasket while reassembling. A proper seal is required
to ensure optimum operation.
4.2.1 Body Gasket Tightening
Should leakage occur at the body joint, tighten bonnet bolts to the values shown in Table 1 (refer
Appendix). If after tightening body bolts, leakage continues, replacement of gaskets is recommended. A
new gasket is recommended anytime the valve is disassembled. The following procedure shown in 4.3 is
recommended for the replacement of the gasket and other trim components.
CAP
BODY
Gaskets
FIG 3. STRUCTURE OF GASKETS IN BODY JOIN
(example only, refer to as-built drawing)
4.3 INSPECTION AND REPLACEMENT OF TRIM COMPONENTS
Disassembly: -
1. Place the valve in the half open position and remove all pressure and drain the system. Make sure that
leakage of any residual material is caught in an appropriate container and disposed of properly.
2. For gear operator or power actuator operated: - remove the bolt fastening the gearbox or power
actuator. Remove the gear operator or power actuator. Remove the bolt fastening the yoke or yoke nut
(depending on size/class).
3. For lever operated: - remove the nut fastening the lever. Remove the lever. Remove the retainer/lock
nut/washer and the stop plate.
4. Follow disassembly procedure 4.4 below.
5. Remove the ball from the body. Check the ball for any damage. Remove the seat from the body. Check
the seat for any damage.
6. Remove the stem and thrust plate from the body. Remove the thrust plate from the stem. Check the
stem for any damage.
7. Clean and inspect body and retainer gasket surfaces. Check for erosion, corrosion, or damage,
especially near point where leakage occurred. If damage is found, those surfaces must be repaired
before continuing.
8. Replace or repair all damaged parts.
