【摘要】 详细分析了新日铁生产的J55套管的化学成分、机械性能及金相组织，指出由于化学成分设计不合理以及热轧工艺不当所造成的晶粒粗大、组织不良等是引起套管韧性低劣并导致射孔开裂的主要原因。同时还应用射孔安全韧性判据的研究成果，论证了该J55套管射孔开裂的必然性。更多还原

【Abstract】 Based on detail analysis of the chemical composition, mechanical properties and metallographic structure of the J55 casing made by Nippon Steel Corp.,Japan,it is concluded that the major causes responsible for the poor toughness and perforation cracking of the said casing areinappropriately designed chemical composition and coarse gains and poor structure due to inadequate hot-rolling process. Also discussed is the inevitability of the said J55 casing perforation cracking on the basis of result from research concerning perforation safe toughness.更多还原