DEVELOPMENT OF DIES WITH DIFFERENTIATED CLAMP FOR CUTTING BLANKS FOR PRECISION STAMPING

Abstract

A large contribution to the final cost of machine-building products is made by the efficiency of blank production, in which a waste-free shear cut is used. The most promising for the implementation of the method of shear cutting are dies with a differentiated clamping of rolled products. The aim of the work is to develop a new die design with a differentiated clamping of rolled products with high technical and economic characteristics and recommendations for the design of such equipment. On the basis of the developed graph of constructions of dies with a differentiated clamping of rolled products, design features have been identified, which made it possible to create a new die design. Compared with the known structures, in the stamp of the DSEA structure, the transverse dimensions and weight are reduced by an average of 25%, and the height of the open stamped space – by 10%. In the process of dividing in the vertical plane, a constant position of the rolling axis is ensured. The transfer of force to the clamp through the rolling is excluded. The stamp has high rigidity. The stamps of the DSEA design have been introduced at the Odessa PJSC "Stroygidravlika". The economic effect of the implementation was 100000 UAH. Acceptance test results showed that the dies of the new design are efficient and reliable in operation. The quality of the cut workpieces corresponds to the quality indicators of the workpieces cut on modern similar equipment. On the basis of theoretical analysis, experimental studies and operating experience of dies with differential clamping of rolled products, known and formulated new recommendations for the design of such dies. The main ones are: it is necessary to provide a differentiated clamping of rolled products on both sides of the separation plane, subject to the condition that the clamping force should be one and a half times greater than the cutting force; the die body is preferably box-shaped to compensate for thrust forces and torsional moments of forces; the power parts of the stamp must be made in a closed form with stiffening ribs to ensure strength under cyclic stress conditions.