Dynamic Characteristics Research On Electric Drive Fracturing Pump Pry Structure

At present,hydraulic fracturing is one of the most important means to increase oil and gas production.As the core equipment of the fracturing unit,the conventional fracturing truck has the disadvantages of high purchase and operation cost,so the electric drive fracturing pump pry is developed.In order to verify whether the vibration characteristics of this kind of fracturing equipment meet the national standards,this paper obtains the dynamic characteristics of the electric drive fracturing pump skid through theoretical analysis,simulation and experimental test,which provides a scientific basis for the use of the electric drive fracturing pump pry.In this paper,firstly,according to the discharge flow characteristics of five-cylinder reciprocating pump and the working principle of electric drive fracturing pump pry,the total discharge flow curve of electric drive fracturing pump pry with the relative installation phase of the crankshaft of the double-pump is derived with the phase of 0,π/10,π/5.The results show that the discharge flow of electric drive fracturing pump pry is more stable with the phase of PI /5.Secondly,according to the actual situation,the mode analysis of pry seat and high pressure manifold of electric drive fracturing pump is carried out.The results show that the modal frequency of the pry seat increases with the increase of the foundation stiffness,but some modal frequencies under the full constraint are smaller than other schemes because the physical model of the pry seat is changed.The modal analysis of the front outlet manifold shows that its natural frequency is low and there is a risk of resonance.In this paper,by observing the modal mode and improving the installation method,the natural frequency of the high-pressure manifold with the improved installation method is greatly improved by finite element calculation,so as to avoid the risk of resonance.Thirdly,according to the operating conditions of the electric drive fracturing pump pry,the fluid-structure interaction analysis of the high-pressure manifold was conducted with the help of the finite element simulation software.The UDF was written to simulate the discharge rate of the electric drive fracturing pump pry,and the influence of different flow rates,pressures and the relative installation phase of the double-pump crankshaft on the manifold was obtained.The results show that the influence of flow rate on manifold is small,and the deformation and stress of manifold increase with the increase of flow rate.The working pressure of the manifold is the main factor of the manifold deformation.The pressure has a linear relationship with the deformation and stress of the manifold.The increase of the working pressure will aggravate the manifold deformation and change the natural frequency of the manifold.The installation phase of the double pump crankshaft has very little effect on the manifold.Generally speaking,the manifold vibrates more smoothly when the phase is π/5.Finally,according to the field conditions and combined with their own conditions,the test mode analysis and dynamic test of the front row outlet manifold of the electric drive fracturing pump pry were carried out.Through experiments,the experimental modal analysis of the manifold shows that the maximum error between the natural frequency of the high-pressure manifold with the improved installation method and the simulation calculation is 13.72%.The dynamic test results of electric drive fracturing pump pry show that the vibration of electric drive fracturing pump pry is small,which conforms to the national standard.On the whole,the experimental results verify the accuracy of the simulation.