Study On The Process Optimization In Forming Grinding Of Premium Thread Gauge

The premium thread gauge are important measuring tools in manufacturing processof the premium thread joints with high value and the most important passing judgmenton the Premium thread inspection. Grinding burn and micro-crack appears on threadgroove, they become the biggest problem in thread forming grinding. This will affect thegauge’s performance and shorten its service life seriously. Thereby, it is necessary tostudy the grindabilty of workpiece material, optimize the grinding parameters andprocess. These works would reduce the production costs, improve the workpiece qualityand bring significant economic value and practical significance. The main contents inthis study include:(1) This paper aims at cold work die steel9Mn2V, and starts with single graincutting finite simulation from four aspects, the chip morphology, grinding force, grindingtemperature and residual stress on the surface. The influences of different cuttingparameters on critical cutting depth, cutting force (ratio), material deformation, cuttingtemperature and residual stress were researched by the simulation single grain cutting.(2) Grinding performances were tested by integrated the simulation result of singlegrain cutting. Firstly, the forms of organization and grinding performances of9Mn2Vunder different heat treatment technics were tested. Then, the comparison of the grindingforce and the grinding surface quality (roughness, residual stress, metamorphic layer)under different grit size, number of reciprocating, feed rate parameters was made. Finally,combining the above results of experimental process, the analysis of the causes andpreventive measures of the grinding cracks can be carried out.(3) The carbide distributional pattern, metallographic structure, and austenitecontent of the workpiece were analysed and compared by different heat treatment process.The relation between the roughness of workpiece and grinding wheel finishing ratio wasverified through experiments. Also, the DOE full factorial experiment was applied to findthe main influence to the quality of grinding wheel dressing. On the basis of optimizeddressing parameter, the target function and constraint condition in two different stageswere established according to rough grinding and precision grinding. Thread grindingprocess parameters were optimized based on the MATLAB. The validity of optimizationwas verified through thread form grinding experiment.