Common faults of pipe joint

In addition to the problems mentioned in the rubber hose assembly and steel pipe assembly, there are two common faults of pipe joint: Cracking of pipe joint and leakage caused by fitting accuracy.

1. Pipe joint cracking

Cracking of pipe joint is a common problem! Impurities and other material defects as well as the strength of the blank! The structure and morphology will cause the cracking of the material! Serious sand holes will directly affect the performance of pipe joint. "When the material is not selected properly, it is easy to cause pipe joint cracking". For example, cold drawn blank is selected for thin-walled parts, its metallographic structure is elongated along the axis, the radial bearing strength is weak, and it is easy to cause cracking during assembly and tightening. "For example, z14 ferrule welded end straight pipe joint produced by a factory is made of cold drawn hexagonal steel, and the user directly welds the joint When it was connected to the oil cylinder, it was found that there were longitudinal axial cracks at the fitting thread of the joint during the test. "The number of cracks was not many, one or two occasionally, less than 1%, but it took time and effort to rework, cut and reassemble" and no cracks were found in the material through flaw detection. After that, more than 1200 joints in stock were extruded with specially designed inner cone indenter (without damaging the fitting surface), and 8 joints were found It was found that the reason for the cracking was that the radial strength of the joint was not enough, and then the forging blank was used to improve its metallographic structure. The problem was solved, and no cracking occurred again.

2. Leakage caused by fitting accuracy

The problem of the dimensional accuracy of the pipe joint is easy to cause oil leakage at the joint. Even if the dimensional accuracy of the pipe joint meets the requirements and ignores the matching accuracy with the steel pipe assembly, rubber hose assembly or other parts, there will be problems. "Therefore, it should be designed reasonably! Production and strict control of its size accuracy problems, in order to reduce and prevent the occurrence of leakage.