无围压射孔技术研究

为了保证施工安全,在射孔完井施工时井筒内要预留一定高度的射孔保护液,这样对于地层压力较低的井,负压值将难以实现,在射孔后射孔液就会进入地层,对地层造成伤害,影响油气井的产能.无围压射孔技术就是研究在高负压甚至无围压条件下实现射孔完井.介绍了无围压射孔技术的研究和初步应用,着重介绍通过对枪体、弹架材料的优选和结构设计,实现了射孔器在无围压条件下射孔完井.无围压射孔枪穿孔后,枪身孔眼、胀径符合SY/T5128-1997标准规定.应用无围压射孔技术对套管和水泥环的伤害较小,满足要求.通过现场应用取得了较好的效果,该工艺技术对低压、低渗油气藏特别是气井的射孔完井具有重要应用价值.

Investigation of Confining Pressure-free Perforating Technique

Under perforating completion there must be certain perforating protective fluid in well bore to assure the operating safety. When formation pressure is lower, the negative pressure will realize difficultly;after perforation the perforating fluid enters into formation to damage formation and effect productivity of the oil and gas well. To solve this problem we developed a high negative pressure and confining pressure-free perforating process. The paper introduces investigation and application of confining pressure-free perforating technique. By optimizing gun and carrier materials and structural design the perforator realizes perforating completion under comfining pressure-free conditions. Post perforation,opening and expending radius of the gun coincide with SY/T 5128-1997 standard. Log information indicates that the confining pressure-free perforating has a little effect on casing and cement mantle, therefore meeting design request. Oilfield application obtained better results. For low pressure and low permeability hydrocarbon reservoirs, especially gas well, this perforating completion process has important application value.