Page 161 - GarlockFluidSealing2010

One of the best methods for determining the cause
of joint leakage is the careful examination of the
gasket where the leakage occurred.
Observation Possible Remedies
Gasket badly corroded • Select replacement material with improved corrosion resistance.
Gasket extruded excessively • Select replacement material with better cold fow properties.
• Select replacement material with better load capacity—i.e., more dense.
Gasket grossly crushed • Select replacement material with better load carrying capacity.
• Provide means to prevent crushing the gasket by use of a stop ring
or redesign of fanges.
Gasket mechanically • Review gasket dimensions to insure gaskets are proper size.
damaged due to overhang • Make certain gaskets are properly centered in joint.
of raised face or fange bore.
No apparent gasket • Select softer gasket material.
compression achieved • Select thicker gasket material.
• Reduce gasket area to allow higher unit seating load.
Gasket substantially thinner • Alter gasket dimensions to move gasket reaction closer to bolts to
on OD than ID due to exces- minimize bending movement.
sive fange rotation or bending • Provide stiffness to fange by means of back-up rings.
• Select softer gasket material to lower required seating stresses.
• Reduce gasket area to lower seating stresses.
Gasket unevenly compressed • Make certain proper sequential bolt-up procedures are followed.
around circumference
Gasket thickness varies • Provide reinforcing rings for fanges to better distribute bolt load.
periodically around • Select gasket material with lower seating stress.
circumference • Provide additional bolts if possible to obtain better load distribution.
• If fanges are warped, remachine or use softer gasket material.
Troubleshooting
Leaking Joints
D-43