Workpiece Precision Oriented Analysis On Coupling Stiffness Of Dies And Press

Precision plastic forming is one of the latest trends of modern mechanical manufacturing technology. This technology can make shape,size and quality of the work piece close to the production furthest. Die and equipment constitute the tool system of precision plastic forming and coupling stiffness of the tool system is the critical factor to the precision of the product.Taking 100MN Numerical control Isothermal Forging Hydraulic Press and precise forming of titanium alloy-TC4 disk piece as the research object, this thesis establishes the FEMA model of Press and has a check on the design of Press. Firstly we obtain the forming force through simulating the forming process of titanium alloy-TC4 disk piece by using plastic FEM and then set up the simplified parametric die-equipment model utilizing the forming force and nominal pressure of the Press as the boundary condition of load. Through altering the height of dies and plates, we get the relationship between coupling stiffness of the Press and flatness precision of work piece and also establish the predictable model for the flatness precision by adopting the modeling method of response surface. The analysis results of coupling stiffness and deform about die-equipment system can be summarized as following:(1) The height of die has a greater effect than supporting sheet has upon the flatness precision.(2) The improvement to the precision of work piece goes weaker and weaker according to the increasing of the height of dies and plates.(3) There is an approximatly linear relationship between the coupling stiffness of die-equipment and the precision of work piece.(4) We can get several combinations between dies and plates when given a precision of work piece, and it makes the optimization of tool system available.