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Thermoplastic Valves Product Guide & Engineering Specifictions
Ball Valve Troubleshooting Guide
Made in the U.S.A. Suitable for Oil-Free air handling to 25 psi, not for distribution of compressed air or gas Page 764
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NOTES: Certain corrective actions of this guide may not be feasible with the Compact Ball
Valve (sealed unit).
Improper system operating temperatures and chemical incompatibility can cause a
variety of functional and structural failures. Be sure to use proper valve material-types
for both temperature and chemical resistance.
Most valve problems are traceable to improper system design or installation. Be sure
to have all design performed by a qualified Engineer and installation made by properly
trained personnel.
Spears
®
valve Installation Instructions and Maintenance/Service Procedures should be
followed in conjunction with all corrective actions.
Structural Breakage
Location Possible Cause
Corrective Action
Handle broken
Body Break
Frozen movements.
External impact.
External impact.
Excessive internal pressure.
System misalignment.
Inadequate valve support.
Chemical attack.
See “Frozen Movements” section. Replace.
Identify and correct source.
Identify and correct source.
Check system pressures and surge pressures;
check for entrapped air.
Check system alignment - end connector(s) must
be parallel.
Provide system support on each side of valve.
Check chemical compatibility of system fluids.
Handle Stripped Overextending open/close range.
Excessive exposure to direct-sunlight has soft-
ened handle material.
Replace handle.
Shield or screen valve from direct-sun exposure.
Stem Sheared / Broken Frozen movements; external impact. See “Frozen Movements” section.
Broken Union Nut
Nut has been over tightened to draw-up or align
end-connectors; external impact.
Inadequate valve supports.
Excessive internal pressure / Hydraulic Shock
Adjust spacing between end-connectors for proper
valve lay-lengths. Check system alignment - end
connector(s) must be parallel.
Provide system support on each side of valve.
Check system pressures and surge pressures; check
for entrapped air.
End Connector Break
System misalignment; external impact.
Over-tighten thread-joint connection.
Inadequate valve support.
Check system alignment - end connector(s) must be
parallel.
Install new end connector according to installation
instructions.
Provide system support on each side of valve.