中文摘要：

气体钻井连续循环短节主通阀可能会遇到阀本体强度失效、阀球转动失效和密封失效等问题.对气体连续循环短节主通阀阀球进行了力学分析,计算出靠人工转动阀球打开主通阀时阀体上、下所需的压力差.对主通阀阀体进行了局部三维分析,分析结果表明,最大应力出现在4个上开口挡圈与阀体的作用面上靠近凹槽根部,最大应力达192.8 MPa,满足强度条件.对主通阀密封进行了设计和计算,主通阀在内、外压差从5 MPa到35 MPa的变化过程中,主通阀的密封副所受作用力都大于密封面必须作用力,保证了所设计的主通阀满足密封性能要求.

英文摘要：

The main valve of continuous circulation joint for gas drilling may encounter issues like valve body failure by lose strength, failure in ball valve turning and seal failure. Mechanical analysis is conducted for the main valve. The pressure difference between top and bottom of the main valve necessary for manually opening the valve is calculated. The three-dimensional analysis of the main valve body shows that the maximum stress occurs on the part of acting surface of the up four split washer and the valve body which close to the groove root. The maximum stress meets the strength requirement with the value of 192. 8 MPa. The main valve seal is designed and calculated. As the external pressure increases from 5 to 35 MPa, the applied forces of sealing pair of the main valve is greater than the necessary force on the sealing surface, which ensures the sealing performance of the designed main valve.