青海油田深探井优快钻井关键技术

青海油田柴达木盆地油藏勘探领域和深度不断加大，其主要勘探领域存在地层倾角大、高压盐水层发育、压力系统复杂多变、地层对比性差、地温梯度高、基岩目的层可钻性差等特点。为解决制约钻井提速、导致事故复杂的技术瓶颈问题，开展了非常规井身结构优化技术、防斜打快技术、高压盐水控制技术、优质钻井液技术、高含二氧化碳地层安全钻井技术、提速工具优化集成技术、深层基岩提速技术等方面研究工作，形成了青海油田深探井优快钻井关键技术。2020年成功钻探4口深探井，平均井深6 017 m，事故复杂率3.41%，平均井底位移110.88 m，应用效果良好。该研究为青海油田后续深探井施工提供了宝贵经验。

Key technologies for optimized fast drilling of deep exploration wells in Qinghai Oilfield

As the oil reservoir exploration field and depth of Qinghai Oilfield in the Qaidam Basin increases continuously, its main exploration fields are characterized by large formation dip angle, developed high-pressure saline aquifer, complex and diverse pressure system, poor stratigraphic correlation, high geothermal gradient and poor drillability of basement target layer. To solve the technical bottleneck problems restricting rate of penetration (ROP) improvement and leading to complex accidents, a series of studies were carried out from the aspects of unconventional casing program optimization technology, deviation control and fast drilling technology, high-pressure saline control technology, high-quality drilling fluid technology, safe drilling technology for formations with high CO2 content, ROP tool optimization and integration technology and ROP technology for deep basement formations, so as to form the key technologies for the optimized fast drilling of deep exploration wells in Qinghai Oilfield. In 2020, four deep exploration wells were drilled successfully with average well depth of 6 017 m, complex accident rate of 3.41% and average bottom hole displacement of 110.88 m, indicating good application effects. The research results provide valuable experience for the construction of subsequent deep exploration wells in Qinghai Oilfield.