Stability of Oil Film and Output Speed of Hydroviscous Drive Affected by the Pressure of Control Oil

Based on the theories of hydraulics and nonlinear control system, the model of hydroviscous drive (HVD) was established, the influences of small ripple of control oil pressure on the output speed of HVD and the stability of oil film between friction disks were analyzed. The conclusion presents that when the frequency of the control oil's pressure ripple is higher than 60?Hz and the peak is less than 0 05?MPa, HVD can work stably. The result is useful for studying the application of frequency conversion technology in regulation of control oil pressure.

二连盆地低渗碎屑岩储层低伤害压裂技术研究应用

二连盆地储层渗透率一般在1×10-3u㎡,有的甚至只有0.1×10-3u㎡。孔隙度平均10%,岩心实验表明80%吼道在0.1um,粘土含量在10-20%,且主要以蒙脱石为主,粘土膨胀性大,储层低孔、低渗特征明显,80%探井需压裂改造来认识储层。以往国内外研究表明针对该类储层低伤害的压裂技术成为该类储层改造的关键。通过多年的研究与实践,逐步形成了新型的综合低伤害压裂技术,具体表现在液体材料上的低伤害特征,压裂施工参数低伤害特征以及压后措施优化低伤害特征。通过利用该技术压后效果获得显著提高。