The accuracy of a CNC machine is a crucial indicator of its performance, which also impacts the accuracy of the workpiece it produces.
CNC machine tool positioning accuracy refers to the ability of the machine’s axes under the control of CNC devices to achieve precise movement. This reflects the static accuracy of the machine tool and is an essential aspect of its original accuracy.
In the case of traditional machine tools with hand feed, positioning accuracy is primarily determined by reading errors. However, CNC machine tools rely on digital program instructions for movement, making the positioning accuracy dependent on both the CNC system and mechanical transmission errors.
The movement of the machine’s moving parts is executed under the control of the CNC device. The accuracy achieved by each moving part directly influences the accuracy achieved by the final machined part, making positioning accuracy a crucial component of testing.
There are seven primary methods for checking positioning accuracy:
- Positioning accuracy test of linear motion
- Repeatability test of linear motion
- Origin-return error accuracy test of linear motion
- Opposite error accuracy test of linear motion
- Positioning accuracy test of the rotary table
- Repeatability test of the rotary table
- ZRN accuracy test of the rotary table
