The test of tensile, impact and low temperature drop weight tests on X65MO steel 22. 2 mm and 24. 0 mm plates, ϕ558. 8 mm pipes and welded joints and the analyzing on structure and performance have been carried out. Through thermomechanical controlled rolling and cooling technology, i. e. the thickness of the billet to be warmed is 88 mm, the re¬duction ratio is greater than 10, the second beginning rolling temperature is set to 870 ~880 ℃ , and the final rolling temperature is set to 820 ~ 830 ℃ , using ultra-fast cooling for cooling i. e. the inlet water temperature is set to 750 ~760 ℃ and the final cooling temperature is 460 ~ 500 ℃ , the mixed structure of ferrite and bainite is obtained, the ferrite content is 50% ~ 60% , and the strength and toughness of pipeline steel pipe meet the customer requirements.

对X65MO钢22.2mm和24.0 mm钢板、Φ558.8 mm钢管及焊接接头进行了拉伸、冲击与低温落锤测试和组织性能分析。通过热机械控轧控冷技术,待温坯厚度88 mm,压缩比大于10,二开温度设定为870～880℃,终轧温度设定为820～830℃,采用超快冷进行冷却,入水温度设定为750～760℃,终冷温度460～500℃,获得铁素体、贝氏体的混合组织,铁素体含量50%～60%,满足了制管后的强韧性要求。