离心式井下增压装置的系统设计

针对目前国内外超高压射流钻井技术采用柱塞式增压器普遍存在寿命短、工作可靠性差的问题,提出离心式井下增压装置的结构设计方案。这种增压装置由动力单元(涡轮动力机)、固液分离单元、增压单元(离心泵)和流道短节单元组成,通过钻井液驱动涡轮动力机旋转,并带动固液分离装置和离心泵高速旋转,使部分钻井液增压,达到提高射流压力和速度的目的。现场试验证明,这种离心式井下增压装置可使钻井液在井底的压力达到30MPa。

Systematic design for a downhole centrifugal supercharging device

In consideration of the problems of short life and poor reliability of the plunger supercharger used in ultra-high pressure jet drilling, a scheme for structural design of a downhole centrifugal supercharging device is proposed. The device is composed of a power unit (turbine plant), solid-liquid separation unit, supercharging unit (centrifugal pump) and a flow channel nipple. The drilling fluid is partially boosted for raising its jet pressure and velocity by rotating the turbine plant with the drilling fluid and bringing the high speed rotation of the solid-liquid separation unit and the centrifugal pump. Field test demonstrates that 30 MPa pressure of drilling fluid at bottom hole can be achieved by using the downhole centrifugal supercharging device.