150t BOF-LF-RH-CC-CR工艺试制石油钻杆连接套用钢SAE4137M

Pilot Production of Steel SAE4137M for Petroleum Drill Pipe Connecting Sleeve by 150t BOF-LF-RH-CC-CR Process

本钢采用铁水预处理-150t复吹转炉-LF-RH-350mm×470mm连铸、M-EMS-连轧工艺生产φ130～170 mm石油钻杆连接套用钢SAE4137M(/%:0.35～0.38C、0.15～0.35Si、0.85～1.00Mn、≤0.015P、≤0.008S、0.90～1.20Cr、0.28～0.33Mo、≤0.005Ca、≤0.0090N)。通过转炉出钢过程加复合脱氧剂,LF扩散脱氧全程吹氩搅拌,RH"软吹氩",严格控制喂钙线量,控制连铸钢水过热度20～30℃,使钢材中氧含量为(13～15)×10^(-6),氢含量(0.4～0.5)×10^(-6),氮含量为(35～44)×10^(-6),残余钙含量(12～18)×10^(-6),并保证钢中Al/N≥2,满足石油用钢的要求。

Abstract The O130 - 170 mm bar of steel SAE4137M for petroleum drill pipe connecting sleeve （/% ： 0. 35 - 0.38C,0.15-0.35Si, 0.85-1.00Mn, ≤0.015P, ≤0.008S, 0.90- 1.20Cr, 0.28-0.33Mo, ≤0.005Ca, ≤ 0. 009 ON） has been pilot-produced by hot metal pretreatment-150 t top and bottom combined blown converter-LF-RH-350 mm × 470 mm casting with M-EMS-continuous rolling process at Bengang. With adding compound deoxidizer during con- verter tapping, diffusion deoxidizing with argon stirring in LF refining, soft argon blowing and strict-controlling feeding cal- cium wire amount in RH refining, and controlling liquid overheating extent within 20 - 30 ℃, in steel products the oxygen content is （13-15） × 10-6, hydrogen content （0. 4-0. 5） × 10-6, nitrogen content （35-44） × 10-6, residual calcium content （12 - 18） × 10-6 and A1/N is ensured ≥12, that all meet the requirement for petroleum steels.