The Design And Flow Field Analysis Of New Construction Machinery Hydraulic Counterbalance Valve

Hydraulic counterbalance valve as an important element in the loop, is widely used in construction machinery hydraulic system. There are many disadvantage in conventional counterbalance valve, such as greater control pressure, poor job stability and reliability, the cylinder can not synchronize the movement, and the structure is complex, difficult process. The article comparatives the advantages and disadvantages of the existing counterbalance valve, and counterbalance valve for excavator has been redesigned to make it smaller pilot control, the larger valve opening degree while working, and good synchronization and stability and master valve can achieve a better match, more coordination.The main contents are as follows:(1)Thesis by analyzing the current situation and existing problems of balance circuit and counterbalance valve, a detailed description of the new counterbalance valve works on excavator and its structural characteristics, and key parts of counterbalance valve were design calculations and simulation analysis.(2) The article also detailed analysis the influence of the number of pressure groove, specifications, groove depth, width and location on its clamping force and leakage. The study found the number of its hydraulic clamping force and leakage have a greater impact. when pressure groove specifications of certain, its hydraulic clamping force and leakage variations stabilized, the change of width have greater impact to leakage,and the groove depth changes are not obvious.(3)By using CFD numerical analysis method to achieve the different conditions, the state of the internal body fluid flow visualization. To different degrees and different flow openings were studied, The researchers found that the degree of valve opening is main factor on affecting its internal pressure distribution, velocity and the streamline, and flow change has little effect on the pressure distribution, streamline.(4)According to the results of visualization of internal flow, the structure has been improved, and oil flow more in line with the objective law of fluid flow, which provide a basis for optimizing the design of the flow channel.(5)Using Hydraulic comprehensive test-bed, the feasibility of its results verifies through a serious of experiment, and explained the reasons for the deviation occurs, which make simulation results more credible.(6) Based on the results of the flow field, using of fluid-structure coupling analysis of specific conditions, the spool of the forces carried out a detailed analysis. The study found that with the increase of the valve opening degree, spool deformation is gradually decreased, when the opening reaches a certain value, the deformation gradually stabilized.