The Quality of Metal Products Made on CNC Machines

Abstract

Contemporary market must provide products that adapt to customer needs, which requires large investments and long-term employment. Producers have to take care of the buyers’ different way of thinking. The quality of products and services is an important economic indicator. The paper presents studies and research in the field of bending of metal parts (thickness between 1 and 3 mm) on CNC machines. This paper tries to provide answers to the many problems arising in the companies due to the quality of the economic goods. In the technological flow of the achievement of a metal product, bending is very important, the quality and conformity of the product depending on this operation. The paper proposes laborious research and studies on determining the drawings of metal parts with the thickness between 1 and 3 mm, considering that other variables such: the temperature variation during the processes of punching and bending, tool usage, the tolerance between the surfaces of the bending tools, the vibrations of the machines, their usage and the roughness of the sheet metals may influence the quality and precision of the products. The calculation of the drawing (the geometry in plane of the piece) becomes important because it must include the deformation caused by the bending operation. Bending coefficients K_î must compensate for deviations from the final dimensions of the metal parts, because of the many variables that can adversely affect their execution. The bending coefficient K_î is determined by experimental tests and measurements.