The three element drive pump failure was the main reason to reduce inspection cycle of the pump. In this paper, a law of pump valve motion in one stroke was acquired through the establishment of the motion equations of the pump valve in the oil well pump, by making it as the pump valve boundary conditions and using ANSYS / LS-DYNA software, the stress state of the valve housing under the conditions of pump valve impact on the valve cover was analyzed, and as the calculation was shown, under the same conditions, the groove valve cover has the stronger impact than the extended grooved valve housing. The inspection cycle of groove valve housing was 457 days shorter than the extended grooved valve cover according to the theory of the fatigue life, therefore, the extended valve housing can effectively extend the check period.

Fracture initiation is a key factor of hydraulic fracturing, as lack of research on fracture initiation position.The perforation geostress mechanical model of low permeability reservoir is built according to the rock mechanics, seepage mechanics, elastic-plastic mechanics, considering solid-fluid coupling and rock material nonlinearity. Adopting the transient analysis, low-permeability reservoir geostress distribution of different stages is obtained using the finite element, such as drilling - cementing - perforation –fracturing. Determine the fracture initiation position and fracture pressure combining with the rock failure criterion. Calculated on well Ao332-32, the error rate of initiation pressure between test and calculation is 3.5 percent. It is proved that the model is reasonable.

Propagation characteristics of crack cross different elastic material interface is important to hydrodynamic fracture of control technology .It makes the specimens of rock and similar materials including interfacial layer to do theItype crack through three-point bending experiments. The text shows that the crack occurred deflection through the interface. Based on damage mechanics, establish the plasticity damage model to describe the sand-mudstone damage behavior. Using the numerical solution technology to simulate the loading cracking process, the experimental and numerical simulation results are in good agreement. The main reason causing the fracture deflection is that the difference of sand-mudstone mechanics of materials property results in interface shear stress increasing, and result in the Itype crack expand transform to the I-IImixed type mode crack. TheII type shear crack makes the crack lateral spreading on the interface. Finally, leading to fracture deflection, the extent of deflection is associated with materials properties of mudstone, Shale content is more low, the deflection is more weak, and vice versa. It is important significance to controlling hydro-fracturing fracture extension.

Horizontal well hydraulic fracture construction technology has already become the main development means of low permeability reservoir, and the crack initiation pressure is a key factor in fracture construction. Taking ABAQUS as the platform, combined with rock mechanics, elastic mechanics, fracture mechanics, damage mechanics and fluid-solid coupling theory, to establish horizontal well mechanical model, crack initiation law of horizontal well under different conditions were obtained by using finite element method. According to the horizontal well fracture tested data in Daqing peripheral oil fields, the crack initiation pressure and numerical simulation results are in good agreement, it shows that the numerical simulation method is reasonable, then analyze influence factor of crack initiation pressure on the basis.

Rational and efficient use of the sucker rod vibration energy is one of the effective ways of pumping unit energy saving. The vibration mechanics as the basis for establishing three-dimensional coupled vibration mathematical model of sucker rod-tubing-liquid column, and using difference solution to reproduce vibration process within one stroke of the sucker rod string, on this basis, analyzing the variable stiffness sucker rod string to the impact of the polished rod load and the pump stroke, and gaining reasonable parameters of the sucker rod string vibration energy, and combining with the working conditions of the sucker rod string to establish the match conditions of the sucker rod string liquid column incentive and polished rod incentive, and proposing the condition of pump to generate over-stroke to provide the theoretical basis for rational use of the sucker rod string vibration energy.