Abstract: With microalloying composition design, intermediate test： 2 t medium frequency furnace-680 kg ingot forging and rolling-φ94 mm x5. 2 mm shell-cold drawn to φ89 mm x 5 mm tube-normalizing at 880°C , and commercial production: 50 t EBT EAF-LF-VD-210 mm x280 mm billet casting- rolled to φ 75 mm tube stock- piercing to φ 75 mm x 5. 5 mm shell- cold drawing to φ70. 2 mm x 5. 05 mm- tube-normalizing at 880 〜890 ℃. , the XGZT850 high strength toughness non-quenched-tempered drill steel tube (/% : 0. 35 ~0. 41C, 0.20 - 0.40Si, 1.40 ~ 1.70Mn, ≤O. 010P, ≤ 0.010S, 0.40 ~0. 60Mo, 0. 04 ~0. 10V, 0.03 ~0.05Ti) is successfully developed. Examination results show that of steel tube the tensile strength is 1 029 MPa, yield strength is 931 MPa and the elongation is 13.5% ; the structure of steel tube is fine and uniform granular bainite ； and the tensile fracture has the characteristic of ductile fracture, and the impact fracture is quasi-cleavage + ductile fracture. The properties of high strength-toughness non-quenched-tempered drill steel tube meet the requirement of user.

摘要： 通过微合金化成分设计,2 t中频感应炉-680 kg锭-锻轧-φ94 mm×5.2 mm管-冷拔至φ89 mm×5.0mm管-880℃正火的中间试验,和50 t EBT EAF-LF-VD-210 mm×280 mm方坯连铸-轧成φ75 mm管坯-穿孔成φ75mm×5.5mm毛管-冷拔φ70.2mm×5.05mm管-880~890℃正火工业生产,成功开发XGZT850高强韧性非调质钻探钢管（/%:0.35~0.41C,0.20~0.40Si,1.4~1.70Mn,≤0.010P,≤0.010S,0.40~0.60Mo,0.04~0.10V,0.03~0.05Ti）。检验结果表明,钢管的抗拉强度1 029MPa,屈服强度931MPa,伸长率达到13.5%;组织为细小均匀的粒状贝氏体;拉伸断口为韧性断口的特征,冲击断口为准解理+韧性断口。该高强韧性非调质钻探钢管性能满足用户的要求。

关键词: 微合金化, 高强韧性, 非调质XGZT85O钻探钢管, 研制