HFC electric-welded pipes made of structural steel with resistance to hydrogen cracking

Abstract

The results of studies carried out in laboratory and industrial conditions, the influence of an integrated approach consisting in the modification of liquid steel alkaline earth metals and rare earth metal, as well as double heat treatment (hardening from the austenitic region at 920 ºC and subsequent high tempering at 650 ºC) of pipes welded with high frequency currents from structural steel with a content of 0.18–0.22 % carbon on the resistance against cracking in H2S-containing media according to the NACE TM 0284 standard are presented. It is shown thatthe adjustment of the integrated approach in terms of limiting the casting rate made it possible to completely eliminate the formation of cracks of hydrogen origin in the metal (CLR = 0 %, CTR = 0 %). A technology for the production of rolled products and pipes welded with high frequency currents with requirements for cold resistance and corrosion resistance in environments containing hydrogen sulfide has been developed. The cost of pipe products made of structural steel with 0.18–0.22 % C, produced according to the developed technology, is less than 2000 rubles/ton compared to similar pipe products made of steel grades 05HGB, 13HFA, 09GSF.