气体钻井钻柱振动特性及控制措施

为解决气体钻井钻柱频繁失效的实际问题，综合考虑钻柱纵横扭耦合振动，根据气体钻井全井段钻柱系统动力学模型分析了气体钻井钻柱的振动特性，并从减振抑振角度提出了空气锤钻井工艺和采用减振减阻工具两种振动控制措施。以川西某实钻井气体钻进段为例，在利用美国ESSO公司现场数据验证全井段钻柱系统三向耦合振动力学模型可行性与结果可靠性的基础上，量化评价了常规气体钻井和采用振动控制措施气体钻井工艺的钻柱振动特性。对比分析表明，这两种工艺措施的减振抑振效果明显，不仅能够有效减弱气体钻井中下部钻柱的振动强度，而且使上部钻柱的动态应力也大大降低。

Vibrating characteristics of drill string in gas drilling and its control measures

To solve an engineering problem of severe vibration and frequent failure of drill string in gas drilling,we analyzed vibrating behaviors of drill string during gas drilling based on a dynamic model for the whole-interval drill string in gas drilling,and presented two control measures against vibration in terms of anti-vibration and anti-drag,namely a well-drilling technique of air hammer and the adoption of anti-vibration and anti-drag tools.Taking a gas drilling section of a field well in west Sichuan as an example,we quantitatively evaluated vibrating characteristics of drill string both in conventional gas drilling and in drilling with vibration control measures,on condition that the feasibility and reliability of the triaxial coupling vibration mechanics model for the whole-interval drill string system were validated with the field data provided by the ESSO Production Co.A comparison indicates that these two technologic measures are of clear effectiveness in anti-vibration and anti-drag,they can not only effectively weaken the vibration intensity of the lower drill string in gas drilling but also remarkably reduce the dynamic stress of the upper drill string.