Press centering test method

Abstract

The invention discloses a press centering test method, which comprises the following steps of: testing and adjusting a pressing plate and a pressing block under the static state of a press and the working pressure of the press respectively, and quickly finding the central position of the working pressure transmission of a four-column press, namely finding the position of the pressure center on a press workbench; and then, a mold is arranged for compression molding according to the determined pressure center of the press, so that the unbalance loading problem of the mold is avoided, the pressing precision of compression molding is improved, the method can be used for near-net-size molding of parts, and post-processing procedures are saved.

Description

technical field [0001] The invention belongs to the technical field of powder metallurgy, and particularly relates to a centering test method for a press. Background technique [0002] Hydraulic press is a kind of mechanical equipment that uses Pascal's principle to transmit pressure through fluid. Usually, three beams, four columns and plungers are used to push the main structure. It is commonly used in molding, forging, stamping, plate pressing, press fitting, straightening and other processing procedures of metal, plastic, rubber, wood, powder and other materials. It is a high-pressure, high-efficiency, low-carbon, and green manufacturing equipment. all areas of the national economy. [0003] Compression molding is to place the molding material in the cavity of the female mold first, and then close the male mold. With the help of the pressure and heat provided by the press, the material is squeezed, deformed, occluded, softened and compressed to fill the cavity, forming ...

AI Technical Summary

Problems solved by technology

However, after long-term attention and use, it has been found that the pressing accuracy of the four-column press is generally low, and it can only be used for blank forming of parts, and is not suitable for near-net size forming with a small amount of processing or no further processing.

[0004] In order to improve the forming precision of parts, the patent 201410841510.1 adopts over-positioning forming technology, which improves the parallelism of the upper and lower working tables of the press under high pressure, and can be used for the pressing of small-sized parts (the size of the mold is less than 50% of the size of the working table of the press); the patent 202110906225.3 solves the problem of centering the mold relative to the four columns (the two axes are concentric), but there is still a phenomenon that the pressure center (referring to the center of the plunger) and the two centers (the center of the workbench and the center of the four columns) are not in the same axis (the three axes are not concentric) ), causing the press to be prone to pressure eccentric loads during work, which in turn affects the further improvement of pressing accuracy

[0005] In order to avoid the eccentric load problem that is common in compression molding, I checked the national standard GBT9166-2009 for the accuracy of four-column hydraulic presses, and found that the press standard with a maximum pressure of 100T and a worktable of 400*400mm only has the flatness and parallelism of the upper and lower worktables of the press under static conditions. Requirements, but there are no relative position indicators such as the flatness and parallelism of the upper and lower working tables under high pressure, the parallelism of the four guide columns, and the coaxiality of the three axes; in addition, there are many methods for determining the center of pressure in engineering (such as: based on Auto_CAD2000 The determination method of die pressure center, patent 201010039114.9), etc., but these methods are mostly drawing method, calculation method, or software analysis method, etc., which have little practical significance

The existing technology cannot accurately measure the position of the pressure center of the four-column press in the project, and a test method is needed to find the pressure center of the press

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