中原油田濮 7区块漏失井固井技术

中原油田濮 7区块漏涌并存，且油气层分散，水层发育，注水井多，出水现象严重，盐层分布散且段长，固井难度很大。针对区块特点，强化了一系列技术措施:完钻通井过程中调整钻井液性能，尽可能做到低黏低切低失水，以保证充分压稳油气层，并用钻进时的 1.2倍排量充分洗井，为水泥浆的胶结和提高顶替效率创造条件；合理选择平衡液达到防漏的目的；使用扶正器提高套管居中度；应用裸眼封隔器有效解决层间水窜问题；优化水泥浆设计，运用塞流顶替、采取分段加回压等项措施。在濮 7-侧 9等 8口井进行了现场应用，取得了固井优良率 100%的良好效果。

Cementing technology for mud loss well at Pu7 block in Zhongyuan Oilfield

Loss circulation and well kick coexist on the drilled wells in Pu7 block of Zhongyuan Oilfield. Cementing operation faces difficulties of dispersive oil and gas layers, developed water contained layers, many injection wells, severe water production, and scattered and long distributed salt bed. According to the area features mentioned above, a series of technology measures are strengthened: in wiper trip process adjustment drilling mud performance after finish drilling, as far as possible to reduce the viscosity, shear force and water loss of the mud, to guarantee the stability of oil and gas layer. Fully clean well by 1.2 times delivery rate of drilling to improve the bonding ability and displacement efficiency of cement slurry; select reasonable balance liquid to prevent loss circulation; use centralizer to enhance the centralization degree of casing; apply open hole packer to resolve the problem of water channeling between the layers; optimizing cement slurry design, displacing under plug flow, pumping back pressure piecewise and other effective measures have been done, that not only stop the oil-gas-water channeling, but also ensure the quality of cementing operation. By application of 8 wells such as Pu7-9 sidetracked hole, achieved good results of 100% fine/excellent rate of cementing quality.