空气钻井中气液合理转换时机和井壁失稳原因及对策

The Reasonable Transference Time of Gas-Liquid and Causes of Well Bore Instability and Strategy in Air Drilling

空气钻进技术在提高机械钻速和缩短油气井建井周期方面发挥了巨大作用,但在钻进过程中地层出水量大或钻遇含有大量的塑性石膏地层等原因,而需要将气基流体转换为气体型流体雾化液、充气,泡末流体或常规钻井流体,但转换时易诱发井壁失稳,导致井下复杂情况。因此,本文探讨了气液合理转化时机,对转化时井壁不稳定机理进行了深入分析,并据此提出了防止井壁失稳的技术对策。

Air Drilling is play the important role in the enhancement of penetration rate and the period of well construction in oil-gas well,but for the layer watering out or meeting the layer containing plasticity gypsum,it also shows the conditions in which the transference of the pure-gas fluids to the Gas-typed Drilling fluids(Aaerated-gas Drilling fluids,Mist gas Drilling fluids and foam Drilling fluids) or conventional mud drilling is very necessary,however when the transference of drilling muds in the operatio...