High-pressure natural gas pipeline fracture critical dimension and service life evaluation method

A technology for natural gas pipelines and critical dimensions, applied in the direction of applying stable tension/pressure to test material strength, special data processing applications, instruments, etc., can solve the problems of calculation result errors, toughness characterization without considering the crack growth process, etc., to achieve calculation Accurate process, saving time and economic cost, simple and convenient processing

Pending Publication Date: 2020-10-30
BC P INC CHINA NAT PETROLEUM CORP +1
View PDF0 Cites 5 Cited by
  • Summary
  • Abstract
  • Description
  • Claims
  • Application Information

AI Technical Summary

Problems solved by technology

The above method does not consider the crack growth process and the toughness characterization o...

Method used

the structure of the environmentally friendly knitted fabric provided by the present invention; figure 2 Flow chart of the yarn wrapping machine for environmentally friendly knitted fabrics and storage devices; image 3 Is the parameter map of the yarn covering machine
View more

Image

Smart Image Click on the blue labels to locate them in the text.
Viewing Examples
Smart Image
  • High-pressure natural gas pipeline fracture critical dimension and service life evaluation method
  • High-pressure natural gas pipeline fracture critical dimension and service life evaluation method
  • High-pressure natural gas pipeline fracture critical dimension and service life evaluation method

Examples

Experimental program
Comparison scheme
Effect test

Embodiment Construction

[0029] The present invention is described in further detail below in conjunction with accompanying drawing:

[0030] A method for evaluating the fracture critical size and service life of a high-pressure natural gas pipeline, comprising the following steps:

[0031] Step 1), take the circumferential material of the natural gas pipeline to be tested and carry out the fracture resistance test, obtain the crack growth resistance curve of the natural gas pipeline to be tested, obtain the parameters k1 and k2 (k1 and k2 average constants) of the crack growth resistance curve according to the fracture resistance test, Let y be the opening displacement of the crack tip, x be the crack growth amount, and the crack growth resistance curve obtained by fitting is y=k1*x^k2;

[0032] Among them, the unilateral notch tensile test is used for the fracture resistance test, the defect depth a0 / W=0.5, a0 is the depth of the opened defect, and W is the height of the unilateral notch test;

[0...

the structure of the environmentally friendly knitted fabric provided by the present invention; figure 2 Flow chart of the yarn wrapping machine for environmentally friendly knitted fabrics and storage devices; image 3 Is the parameter map of the yarn covering machine
Login to view more

PUM

No PUM Login to view more

Abstract

The invention discloses a high-pressure natural gas pipeline fracture critical dimension and service life evaluation method; the method includes obtaining a crack propagation resistance curve of the to-be-tested natural gas pipeline through a fracture resistance test; obtaining the yield strength and the tensile strength of the to-be-tested natural gas pipeline through a tensile property test; calculating the parameters of the fracture toughness of the material according to the crack propagation resistance curve of the natural gas pipeline to be measured, the parameters of the resistance curve, yield strength and tensile strength; establishing a crack tip opening displacement relation; obtaining crack tip opening displacement under different crack depths under the action of fixed internalpressure; determining the critical dimension of the crack when the pipeline fails according to the competitive relationship between the crack propagation driving force and the resistance; and reflecting the whole service process from the growth of failure cracks of the pipeline. According to the invention, the material crack propagation resistance of the pipeline is considered in the calculation process, the calculation process is more accurate, tests required by the method belong to conventional tests and are easy to carry out, the treatment process is simple and convenient, and time and economic cost are saved.

Description

technical field [0001] The invention relates to the field of natural gas pipeline hazard assessment, in particular to a high-pressure natural gas pipeline fracture critical size and service life assessment method. Background technique [0002] During the service of natural gas pipelines, due to geological disasters, corrosive media, human factors, quality problems, etc., the pipelines may break, deform, fail, corrode, etc., resulting in continuous loss of metal in pipeline materials (pipeline crack growth), which has Serious hidden danger. [0003] When there are defects in the pipeline, under certain conditions, the pipeline will experience unstable expansion at the crack, which will cause the pipeline to break. How to accurately calculate the critical size of the pipeline crack instability and estimate the service life of the pipeline is a key issue in the study of the safe service behavior of the pipeline. [0004] In engineering, the method of residual wall thickness a...

Claims

the structure of the environmentally friendly knitted fabric provided by the present invention; figure 2 Flow chart of the yarn wrapping machine for environmentally friendly knitted fabrics and storage devices; image 3 Is the parameter map of the yarn covering machine
Login to view more

Application Information

Patent Timeline
no application Login to view more
IPC IPC(8): G06F30/20G01N3/08G06F113/14G06F119/02G06F119/04G06F119/14
CPCG01N3/08G06F30/20G06F2113/14G06F2119/02G06F2119/04G06F2119/14
Inventor 杨坤陈宏远池强封辉来建刚贾鹏军
Owner BC P INC CHINA NAT PETROLEUM CORP
Who we serve
  • R&D Engineer
  • R&D Manager
  • IP Professional
Why Eureka
  • Industry Leading Data Capabilities
  • Powerful AI technology
  • Patent DNA Extraction
Social media
Try Eureka
PatSnap group products