Blank Size Benchmark Theoretical And Applied Research

For mechanical products design, blank manufacturing is the first step of the Mechanical Manufacture, it is important to improve the precision of the parts, reduce costs, ensure the whole manufacturing completed successfully. At present, the blank size design is mostly got with plus or minus total machining allowance in the basis of parts' drawing size. This design method is simple and widely accepted by society, People have formed the habit. But this method of select blank datum and calculate blank dimension is not very reasonable. Because it can't guarantee both the blank minimum tolerance of the machined surface rough machining allowance and the minimum size and positional error between the non-machined surface and machined surface.This paper each processing surface rough machining allowance requiremints of tolerance, as well as various the processing surface and processing surface position error between size and two aspects of optimization scheme for research. Using the method of establishing blank dimensions, conduct analysis and optimization, concluded that more reasonable mark mode. This method not only looking for simple, easy to blank size relations to express the structure characteristics, blank diagram for the realization of blank dimensions and computer optimization provides a feasible new ways.In this paper the completed the following job:(1) Through analyze the relationship between the blank ingredients, this paper defines the concept of the blank dimensions formula, and research the blank dimensions, mechanical machining allowance and tolerance grade in the national standard, provide theoretical and parameter support for the follow-up work.(2) In this paper, Chapter four and five through the method of blank size formula and route map of the position relations, take a detailed analysis of the rough machining allowance and tolerance of all the blank surfaces, and take a specific analysis of the size and location error between the non-processed surface and machined surface, propose the optimization programs and solutions. (3) With examples, with the use of VB and Access 2003 database as the development platform of the application software, developed a simple and practical procedure for the blank size calculation, and make a detailed implementation of the process of this program.