Limited by the harsh downhole working environment and its structural feature, the sliding vane pump (SVP), which is an all-metal artificial lift method considered to be widely used in thermal recovery well and high gas/oil ratio well, has not been widely applied as expected. To further improve the efficiency of SVP, this study explores how to optimize the structure parameters and the usage of the pump based on its lifting characteristics, in view of the stagnation in the development of SVP. The main results show that (a) optimization of the inlet (outlet) position parameters will bring effective pre-expansion (precompression) of each chamber once it enters the closed state, to avoid ineffective suction and high-pressure backflow. (b) The mathematical model of the pressure difference between the two sides of the vane at any position is derived by means of piecewise function. (c) Increasing the number of vanes can not only increase the mean value of instantaneous displacement but also shorten the discharge period and reduce the flow pulsation. Compared with the adjacent even number of vanes, the odd number of vanes has a more uniform instantaneous displacement. (d) A larger cross-sectional area of the rotor groove can result in a lower volume efficiency at the same gas-liquid ratio, and the effect of rotor groove on volume efficiency is more significant under high gas-liquid ratio conditions.

In the field application of oil and gas well drilling, it is found that the previous mechanical specific energy (MSE) model cannot well monitor the data of rotary impact drilling, and there are great errors. The main reason is that these MSE models focus on the correction of hydraulic and rate of penetration (ROP), ignoring the impact energy generated by hydraulic impactor, thereby reducing drilling efficiency (DE). Therefore, this paper improves weight-on-bit (WOB) and hydraulic parameter displacement Q to establish the rotary hydraulic impact specific energy model (RHISE) of polycrystalline diamond compact (PDC) and roller cone bits, and establishes the corresponding bit optimization model (BO) considering drilling cost (CT), RHISE, wear evaluation index (WI) and ROP. Applying this model to four wells in Shunbei, results show that the ROP of roller cone bits increases by about 10% and the DE increases by about 8% compared with the PDC bit. Compared with the combination of staggered PDC and roller cone bits (RCB) with hydraulic impactor, DE increased by 16% and BO increased by 4%. Therefore, the comprehensive efficiency of RCB combined with hydraulic impactor is better than that of PDC bit combined with hydraulic impactor.