GLOBE VALVES OS & Y - FORGED - ISO 15761/API 602/B16.34
Australian Pipeline Valve - Installation, Operation and Maintenance Manual
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3. Bonnet bolt tension should be checked periodically when valves are used in high temperature
applications where creep may occur. (see Tables A & B, Appendix A, and Figure 10). Although leaks
through bonnet ring or spiral gaskets are rare, erosion or corrosion could cause bonnet seal to fail. In
these cases, a new gasket is required. Refer Sections 4.3.1 & 4.3.2 for replacing bonnet gasket.
4. With problematic service applications it is recommended that the valve be periodically at least
partially stroked to ensure valve functions and to ensure there is no product deposits entering into seat
or stem area which may render operating more difficult. Duration depends on service, criticality, etc.
However, it also must be factored in that if there are impurities or particulates in the line, likely to be
built up in the seat area, each operation could reduce seat life proportionately.
3.5 LUBRICATION
Regular maintenance of the valve is required to assure smooth operation. Stem threads should be
inspected and lubricated frequently to ensure ease of operation. APV valves are supplied with the stem
threads engaging the yoke nut pre-greased. These components should be kept constantly lubricated by
applying the grease directly on the stem when the valve is in the open position or through the grease
injector in the yoke nut when provided. Lubrication/greasing of the stem should be conducted every six
months or more often as needed, based on the environment the valve is installed. Inspection should
confirm that the valve is sealing properly. Stem packing should be inspected at least every six months to
ensure zero leakage from the packing chamber. For water & oil service, regular maintenance should be
scheduled every 3 months. For more corrosive mediums, inspection and maintenance should be completed
once a month.
3.6 BONNET BOLT TENSION
Bonnet bolt tension should be checked periodically when valves are used in high temperature applications
where creep may occur. Although leaks through bonnet ring or spiral gaskets are rare, erosion or
corrosion could cause bonnet seal to fail. In these cases, a new gasket is required. Refer Sections 4.3.1 &
4.3.2 for replacing bonnet gasket. Refer Appendix A, Tables A & B and Figure 10 for torque figures and
tightening sequence.
3.7 PERIODIC STROKING
With problematic service applications it is recommended that the valve be periodically at least partially
stroked to ensure valve functions and to ensure there is no product deposits entering into seat or stem
area which may render operating more difficult. Duration depends on service, criticality, etc. However, it
also must be factored in that if there are impurities or particulates in the line which are likely to be built
up in the seat area, each operation could reduce seat life proportionately.
APV globe valves have one point of lubrication, the stem/yoke sleeve threads. Lubricate as follows:
- For APV globe valves with grease fitting, lubricate through the fitting.
- For APV globe valves without grease fitting, open the valve to half stroke.
- Brush lubricant on the stem threads above and below the yoke nut.
- Run a complete “open-close” cycle, the stem/yoke are now lubricated.
