Papers by Keyword: Shaping Law

Abstract: The twiste angle has a great effect on shaping law and stability of Numerical Controlled Electrochemical Machining (NC-ECM) process. In order to avoid the disadvantages caused by twiste angle, a methode of study shaping law by dispersing cathode working face in NC-ECM was proposed, and a mathematical model of the shaping law with the effects of twiste angle has been established in this paper. The mathematical model disclosed the relationship of twiste angle β, feeding velocity v_f and thickness of removal material h in NC-ECM. Theoretical and experimental results show the the mathematical model of shaping law described in this paper can be considered as a useful reference and is helpful for the analysis of the NC-ECM and general ECM process.

Abstract: Lots of integral impellers are used in the new kinds of jets. The jet engine weight can be lightened much, and the thrust,work life and the safety coefficient can be increased remarkably. Based on the integral impeller’s structure features and the processing difficulties with special complex blades, the shaping law on electrochemical contour evolution machining the blades is analyzed and studied, the multi-axis linkage movement feed tracks are designed optimum by the shaping laws and the tests. The combined cathode with the reasonable flowing fields is designed, there is an eccentric between the cathode sole plate and cathode body, the bidirectional feeds method is adopted, the short circuit and electro-discharged sparks damages are eliminated. The redundant rests in blades back is removed by adding wobbly feeds. Machining tests are carried out. The blades satisfying precision are produced.

Abstract: While the surface of integral impeller blade was electrochemically machined, cathode cannot rotate in accordance with other movement axes, which results in nonuniformity in velocity of electrolyte and normal direction of the machining blade surface, thereby causing inaccuracy in the machined blade surface. In order to solve this problem, the shaping law was studied in Electrochemical Finish Machining. Then relative positions between cathode slot and blade surface were analyzed during the process of Electrochemical Machining (ECM). Three parameters, namely feed direction, feed velocity and initial machining inter-electrode gap, were adjusted to conduct the fundamental experiments when direction of cathode slot was changed. Afterwards machining accuracy as well as surface quality of workpiece was analyzed. Finally according to experimental results, direction of cathode slot was determined practically in electrochemical machining process and the integral impeller blades meeting the requirement were electrochemically machined.

Abstract: Numerical Controlled Electrochemical Contour Evolution Machining (NC-ECCEM) is one of the most important development in Electrochemical Machining (ECM). In order to improve the machining accuracy of NC-ECCEM technology, the research works on precision NC-ECCEM technology are needed, and especially the study on its shaping law is significant for improving the machining accuracy of workpiece profile. In this paper, the shaping law of machining the planar surface by use of a kind of inner-spraying cathode with rectangle section was studied. First, the basic differential equations of shaping law in the case of cathode movement were established. Then, considering the structure of the cathode, the methods for calculating the side gap in machining the planar surface was given. Finally, the experiments of machining the planar surface were carried out. Experiments show that the calculated side gaps are bigger than the actual values, but the change trend of calculated side gaps with machining process parameters is coincident with the actual side gap change trend.