摘要 |
FIELD: metallurgy.SUBSTANCE: in order to increase the level of viscoplastic properties, provide operating reliability of metal in a weld joint zone of drill pipes with friction-welded locks, heat treatment of the weld joint zone is performed, which involves heating for austenisation to the temperature of Ac3+(70÷120)°C, cooling and tempering in the temperature range Ac1÷80°C, and as per the second version, heating for austenisation to the temperature of Ac3+(70÷120)°C, cooling, additional heating at intercritical interval of temperatures Ac1+(30÷80)°C, and tempering.EFFECT: invention allows increasing level of impact operation so that stable values of at least 16 J are obtained and at least 42 J at increased test temperature of minus 20°C, and the invention allows increasing structural service life of weld joints of drill pipes.2 cl, 1 tbl, 1 dwg, 2 ex |