Dimensional aspect of the capability of CNC-machining technologies

Abstract

The paper refers to the dimensional aspect of ensuring the CNC machining capability of parts with complex dimensional structures. CNC machining capability is treated as a correlated pair of characteristics: machining allowance – machining accuracy. In complex technological dimensional structures, 3 structural effects are manifested: 1) increasing the precision requirements imposed on technological dimensions, 2) increasing the machining allowance tolerances, and 3) reducing the machining allowance tolerances and technological dimension tolerances due to error compensation mechanisms. These structural effects for the dimensional structures “fan-shaped”, “displaced fan-shaped,” and “chain” have been analyzed and characterized. The possibility of increasing the CNC machining capability by equivalently replacing dimensional structures that do not ensure CNC machining capability with others is demonstrated. The positive effects of the structural transformations: “fan-shaped”-“displaced fan-shaped”, “chain”-“fan-shaped”, and “chain”-“displaced fan-shaped” are analyzed.