Stress oriented hydrogen induced cracking
Tianjin Rong Da Testing Co., Ltd. contact: Wang Jingfu
Cell phone: 13102238283 QQ:3144667033
Telephone: 022-23892103
HIC anti hydrogen induced cracking is suitable for hydrogen corrosion resistance.
Hydrogen induced cracking test is an analysis of the influence of the corrosion resistance of steel on the corrosion resistance of the sample under wet hydrogen sulfide environment. The effect of hydrogen absorption on the corrosion of hydrogen is determined by the performance of steel.
Hydrogen: hydrogen embrittlement is steel by high temperature and high pressure hydrogen, metal steel caused by chemical changes, the strength and plasticity of steel decreased fracture to brittle fracture phenomenon called hydrogen embrittlement.
Hydrogen embrittlement conditions:
Hydrogen does not produce obvious corrosion of steel under the normal temperature, but when the temperature is over 300 DEG C and a pressure higher than 30MPa, this will produce hydrogen embrittlement corrosion defects, especially under high temperature conditions.
The values of the following hydrogen corrosion of the standard is NACE TM 0284-, NACE RM0175, created by GB/t8650:
1, crack sensitivity ratio CSR
2, crack length ratio CLR
3, crack thickness ratio CTR
Hydrogen induced cracking for an adverse effect of pipeline and pressure vessel steels are cracks along the rolling direction. A planar crack tends to crack near the connection level. To produce a ladder shaped crack along the thickness direction. These cracks reduce the effective wall thickness of pipeline steel or until the pressure vessel stress service or sometimes accompanied by surface crack damage. Hydrogen bubble will appear at the same time. There have been reports of service failure attributed to the crack.
Before the ladder shaped crack. The pressure of hydrogen bubble and crack crack. Hydrogen induced crack description stepped pipeline and pressure vessel steel crack type. But now it has been abandoned. Now is widely used in hydrogen induced cracking (HIC) to describe the crack type. And by international organizations using NACE