Reasons Analysis and Solution Measures of Cracks of Petroleum Drill Pipe Weld

Formation causes of cracks found during drill pipe weld manufacturing inspection process were analyzed combining with the actual manufacture and heat treatment process analysis. The results show that mostly cracks were found at the joint ektexine near the weld line and resulted from the big inherent stress of the quenching process. To resolve this problem, the quench temperature was lowered to Ac1-Ac3, which was equal to subcritical quenching and high-temperature tempering. After adjusting the heat treatment process, the weld quenching cracking could be avoided completely. At the same time, the products performance also well met the technique requirements.