Structure Optimal Design Of Key Components Of High Pressure Fracturing Pump

Petroleum shortage along with environment destruction is becoming more and more serious.It is emergent for human beings to promote the ability of exploiting the fossil fuel and seek the alternatives.At this point,fracturing technology come into being,a technology which can significantly enhance oil extraction of oil land.In the meantime,fracturing technology is the key issue of exploiting shale gas.Fracturing pump is the central section of fracturing sets,the prosperity of which can directly affect the efficiency of oil exploitation.In this paper,the key components of high pressure fracturing pump power end are taken as the research object,structural topology optimization design and size optimization design are carried out.Based on the lightweight,the fracturing pump box components with superior performance are obtained.The force analysis model of the hydraulic pump end is established,and the force analysis is carried out by the analytic method.As crankshaft is a statically indeterminate structure with multiple supports,under appropriate hypotheses,applied forces between components,such as reactions of bearing pedestals,can be identified using “the segmented capitation method”.Meanwhile,based on the Lagrange equation method in dynamic theory,virtual prototype model of the power end of the fracturing pump is established using dynamic analysis software ADAMS.To solve the statically indeterminate problem,crankshaft is segmented and connected with dumb elements.The loads obtained in ADAMS simulation basically coincide with theoretical analysis results,which verifies the correctness of the analytic method,and provides significant theoretical basis for the structural optimization design of key components in following passages.A mathematical model of multi-objective optimization for the design of the pump casing is established based on the variable density method and in the meantime the static stiffness and the low order natural frequency of the multi operating conditions are taken into account.The topology optimization design of the fracturing pump box is carried out by using the optimization software Optistruct,and the optimal topology structure of the pump case considering the structural stiffness and dynamic performance is obtained by the iterative calculation.According to the topology optimization results,the structural design of the pump casing is established,which lays the foundation for the optimum design of the box structure.The parameterized modeling is completed based on topology optimization in the design of fracturing pump box.The use of the response surface method,in the box of fracturing pump mass,the maximum equivalent stress and maximum deformation of the most optimized target,is introduced to establish the optimization mathematical model of fracturing pump box size.With the experimental design method to get the box size design response space,addition to genetic algorithm,fracturing pump key dimensions by multi objectives are obtained,dynamic and stable performance of the box structure before and after optimization are compared,which indicates that the optimized box structure not only reached the target weight,but significantly promote its strength and stiffness,which provides an effective method for the structure optimization design of fracturing pump key components.