|
Appearance
|
Cause
|
Remedy
|
|
Fact
|
Conditions
|
|
Breaking
|
Broken at one or two places on the circumference of the packing. |
|
(1) Packing twisted when installed.
(2) Assembled with improper packing installation. |
(1) Improve the method and tools of installation. |
| Fine cracks all over the surface of packing. |
|
(1) Ozone cracks by exposing packing to air too long.
(2) Ozone cracks by leaving installed with piston. |
(1) Avoid direct sunlight and store packings in a dark place. |
| The heel part on the sliding side is broken. |
|
(1) Extrusion gap was too large.
(2) Bearing worn too great causing a large gap.
(3) Too much pressure. |
(1) Reduce extrusion gap.
(2) Use a back-up ring.
(3) Change back-up ring to that of high wear resistant material. |
| Part of the heel on fixed side is broken. |
|
(1) The construction of installation part is inappropriate.
(2) Deformation occurred due to insufficient rigidity of support plate.
(3) Inappropriate back-up ring. |
(1) Correct chamfering.
(2) Improve rigidity of support plate.
(3) Correct the size of back-up ring.
(3) Change back-up ring material to appropriate one. |
| Both the heel of the sliding part of the packing and back-up ring are extruding. |
|
(1) Too much extrusion gap.
(2) Inappropriate back-up ring. |
(1) Reduce extrusion gap.
(2) Change back-up ring to that of a more rigid material.
(2) Make thickness of the back-up ring larger. |
