The Research And Manufacture Of 200T Automatic Powder Metallurgy Press

The property of powder forming press is a decisive factor for the quality of compacts as a key equipment of powder parts products line,wherever which restricts the development of powder metallurgy industry. At present, developed countries at abroad have produced powder presses that can applied to complicated shape,high required geometric tolerance,large batch compacts, and these countries possess mature hydraulic press based on the proportional technology that has been blockaded. The universities and institutes in the domestic which undertake the research for the high property powder press are few, in addition partial enterprises produce the powder press that has no perfect property and small scale, moreover the research of powder press at home and abroad focuses on improving the motion precision of the forming hydraulic press. In the thesis, the theory of powder pressing is analyzed based on the referencing the relative information in a few domestic universities which have been developing the powder press field, so the thesis has done a little preliminary research and designed the hydraulic system according to the theory.The thesis introduces the theory of pressing for the 200t powder press, servo adaptor and the craft of producing the compacts, the design and calculation of hydraulic system are completed on the basis of practical operation condition of the 200t powder press specificity and referencing the powder press hydraulic system at home and abroad. Starting guarantee the same pressing velocity for obtaining uniform compact density, the control system of the proportional direction valve is selected combining the advantages of the electric and hydraumatic, which has good control property to be controlled easily. Through calculating the parameter such as the flow and pressure of the hydraulic loop and components, the main components type are selected. The proportional position control of the main cylinder is the important composition of hydraulic control system of powder press, based on the consecutive flow equation of hydraulic system and force balance equation, the transferring functional mould of each link is set up, at last the block diagram of the transferring function is deduced for the whole valve controlling cylinder system, and the main parameter values in the model are determined.The builded system model is simulated and the property is analyzed and rectified using MATLAB and SISO TOOL for improving the system response velocity and stability, in the last, the position stiffness disturbed by the load is analyzed for the rectified system, the simulation result satisfy the control requirement of the powder press.