Analysis of flow field for electrochemical machining deep spiral hole with gradually changing groove section

The electrochemical machining (ECM) technology is applied to the rifling processing field to solve the problem that new structure rifling with gradually changing grooves cannot be processed. By establishing the mathematical and geometric models of flow field in ECM gap, the distribution state of the deep spiral hole with gradually changing groove flow field in ECM gap was studied. By analyzing the simulation results of the flow field, it can be seen that the electrolyte is not evenly distributed in ECM gap and the electrolyte flow rate is insufficient at the tail of cathode process zone. Therefore, the cathode structure was secondarily improved to improve the electrolyte flow field distribution, so as to establish an optimized cathode model. Carry out ECM experiments of the deep spiral hole with gradually changing grooves and test experiment results under different parameters. The relationship between process parameters and deep spiral hole with gradually changing groove size can be obtained by analyzing the test results. The test results show that when the voltage varies from 12 to 18 V, the section shape of gradually changing groove rifling is respectively changed to 0.54 mm in diameter and 0.31 mm in groove width; for every 2-V increase in voltage, the average increase in diameter is 0.18 mm and in groove width is 0.10 mm. The simulation in ECM gap by using COMSOL is effectively shortening the cathode development cycle. The realization of ECM deep spiral hole with gradually changing grooves lays a technical foundation for the leap from design theory to engineering practice.