Cause analysis of flaw detection disqualification of steel for DH36 offshore platform and process improvement
Utilizing ultrasonic flaw detection technology,a comprehensive inspection was conducted on steel plates after rolling,and a systematic analysis was performed to identify the causes of flaw detection.The causes of cracks and inclu-sions result from Nb and Ti were elaborated,revealing the microstructures and maromorphology of these defects.Adopting KR hot metal desulfurization:The hot metal adopts a full slag removal process,with the incoming S less than 0.005％,hot metal temperature more than 1 340 ℃,converter compound blowing throughout the process with argon,endpoint carbon content controlled between 0.04％-0.06％,utilizing a slide gate for slag retention,and a steel tapping time more than 4 minutes,etc.The implementation of these measures is vital for ensuring the safety and reliability of steel used in ocean platforms and contributes to quality control in the steel industry.
steel for offshore platformflaw detectioninclusioncrack
NETL
NSTL
万方数据
