Causes of occurrence
Rotation of the material in the link hole when turning the bushing, the material in the link holes is pulled out by mutual rotation of the pin and the bushing. Factors contributing to the defect occurrence.
-
Dimensional deviations when boring holes in a link, press-fitting surfaces at pins and bushings at their manufacture,
-
Shear metal of the link instead of being pressed into the pin or bushing due to improper adjustment of the assembly press or assembly tool for assembling the track chain
-
Severe repetitive shock loads in service (overly wide shoes )
Produced effect
Loss of press interference fit in the link, which can lead to the release of the pins and the destruction of both track parts and parts and elements of other units of the undercarriage system. Loss of lubrication and inability to use links, bushings and pins for repair.
Prevention and elimination.
-
Control over the observance of dimensions in production of links, pins and bushings
-
Control over the correct adjustment of the equipment and the press when assembling the track chain
-
Elimination of controllable factors that accelerate defects appearance.