ø73 mm小尺寸涡轮钻具叶型设计及优化

小尺寸涡轮钻具主要用于深部高温硬岩地层钻进,对我国油气、干热岩等深部能源矿藏的地质调查具有重要意义,在石油行业中小井眼钻井、老井加深及连续油管钻修井等方面具有较好的应用前景。目前,国内尚无ø73 mm小尺寸涡轮钻具,为推进涡轮钻具系列化,对ø73 mm小尺寸涡轮钻具的涡轮节中常规级定转子叶片及制动级定转子叶片进行设计优化,旨在研制长度短、转矩适中、转速适中、压降小、功率高及效率高的ø73 mm小尺寸涡轮钻具,使ø73 mm小尺寸涡轮钻具尽快在我国实现现场应用。设计出符合性能要求的3种常规定转子叶型方案和5种制动级叶型方案,通过理论分析及数值模拟,选出最优的常规定转子叶型及制动级叶型方案,并提出常规涡轮级与制动涡轮级复配的5种涡轮节结构方案,同时对涡轮节结构进行了性能分析及方案优选,优选的涡轮节方案在流量5.5 L/s,工作转速1 500～2 500 r/min时,输出转矩为109～140 N·m,平均压降为11.5 MPa,制动转矩为185.5 N·m,可满足小井眼钻井对ø73 mm小尺寸涡轮钻具的输出性能要求。

Design & Optimization of ø73 mm Diameter Slimhole Turbodrill Stator & Rotor’s Blade Profile

Slimhole turbodrill is mainly used in drilling deephigh-temperature hard rock formations, which is very important to the geological survey of deep energy minerals in China, such as oil and gas, dry hot rock and so on. It’s also applied in these prospects such as slim hole drilling, deepening of old wells and coiled tubing downhole operations in petroleum industry. There was no 73 mm diameter slimhole turbodrill in China. In order to promote the serialization of turbodrills, the design and optimization of 73 mm diameter tubine stage blade profile were carried out. The purpose is to design the slimhole downhole turbine motor with characters of long distance, high output torque, low rotating speed, low pressure drop, high output power and high efficiency, and make the small-size downhole turbine motor to be applied in fields practice as soon as possible. 3 schemes of conventional turbine stage and 5 options of braking blade stage were proposed. Through theoretical analysis and numerical simulation, the optimal conventional stator and rotor blade profile and brake stage blade profile were selected, and five turbine section structure schemes of the conventional turbine stage and the brake turbine stage were proposed. At the same time, the performance analysis and scheme optimization of the turbine section structure were carried out. The selected turbine section scheme has a flow rate of 5.5 L/s and an operating speed of 1 500～2 500 r/min, an output torque of 109～140 N·m, an average pressure drop of 11.5 MPa, and a braking torque of 185.5 N·m. It can meet the output performance requirements of ø73 mm small-size turbodrills for slimhole drilling.