Method for predicting residual life of in-service gas polyethylene pipelines

Abstract

The invention discloses a method for predicting residual life of in-service gas polyethylene pipelines, and belongs to the technical field of polyethylene pipeline life prediction. According to the method, an accelerated ageing experiment is carried out on a polyethylene pipeline having the same mark with an in-service polyethylene pipeline to prepare an aged polyethylene pipeline according to method requirements, and the ageing time, the temperature and the pressure are recorded; and a differential heat scanning method is used for testing an oxidation induction period of the aged polyethylenepipeline, and an oxidation induction period data set is recorded to obtain a residual life prediction formula (as shown in the specification); and finally, a few smalls are scraped from the surface of the in-service polyethylene pipeline to carry out a differential heat scanning method test, and an obtained oxidation induction period numerical value is substituted into the a0 of the residual lifeprediction formula to carry out calculation so as to predict the residual life of the gas polyethylene pipeline under operation state. The life prediction method does not influence the normal operation of urban gas polyethylene pipelines, is simple and time-saving, has a certain data distinguishing ability and is capable of providing technical support for the safe operation of in-service gas polyethylene pipelines.

Description

technical field [0001] The invention belongs to the technical field of life detection of polyethylene pipelines, in particular to a method for predicting the remaining life of polyethylene pipelines for in-service gas. Background technique [0002] Due to the characteristics of corrosion resistance, light weight and low frictional resistance of polyethylene pipes, polyethylene pipes have been widely used in urban gas pipeline transportation. However, polyethylene is a polymer material and is prone to aging, so polyethylene pipes have the problem of aging failure. At present, the transportation of gas-fired polyethylene pipelines in service needs to be operated under a certain pressure. The service life of gas-fired polyethylene pipelines under a certain pressure is a very important indicator in engineering applications. The national standard stipulates that the temperature is 20 ℃ The service life of polyethylene gas pipeline is not less than 50 years. At present, the ISO9...

AI Technical Summary

Problems solved by technology

This method has little integration with the actual working conditions, the test time is long, and the pipe needs to be cut from the in-service pipeline for the test, which will seriously affect the normal operation of the gas pipeline, and there will also be safety hazards in the secondary welding of the pipeline

[0005] Low-property aging polyethylene pipes have been used for decades, and gas polyethylene pipes are mostly distributed in densely populated areas. There have been many polyethylene gas pipeline explosions and leakage accidents at home and abroad, causing serious economic losses and even endangering Personal safety

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