蓄能液气泡钻井液流变性能研究

设计并研制了蓄能液气泡钻井液流变性能测试装置,该装置能模拟井下100℃、20 MPa环境,建立了高温(100℃)、高压(20 MPa)条件下蓄能液气泡钻井液流变性能的评价方法。研究表明,研制的蓄能液气泡钻井液表现出良好的剪切稀释特性,携屑能力强;泡沫质量对蓄能液气泡钻井液的流变性能影响很大;由于蓄能液气泡钻井液抗压能力强,因此压力对其流变性影响不大;温度对体系的流变性能是通过影响液相黏度来实现的;气体类型对蓄能液气泡的流变性能影响不大;此外,现场应用时可通过改变发泡剂加量(影响泡沫质量)和搅拌速率(影响泡沫粒径)来调节体系的流变性能。

Study on Rheology of Aphron Drilling Fluid

A testing device was developed for the measurement of the rheology of aphron drilling fluids. This device has the capacity of simulating downhole temperatures to 100 ℃ and downhole pressure to 20 MPa. A procedure for the testing of the HTHP rheology of aphron drilling fluids is established. A newly prepared aphron drilling fluid is tested using this device, showing good shear thinning property. Foam quality greatly affects the rheology of the aphron drilling fluid. Pressures, on the other hand, do not obviously affect the rheology of the aphron drilling fluid because of its high pressure resistance. Temperatures greatly affect the viscosity of the liquid phase, thus plays great role in determining the rheology of the aphron drilling fluid. Types of gases have little effect on the rheology of the aphron drilling fluid. In field application, the rheology of the aphron fluid can be adjusted by changing the amount of foamers and agitation speed.