How many errors do you know in the machining of these precision parts?

1. Processing principle error

The principle error of CNC machining is caused by the use of approximate machining motion methods or approximate tool contours. Due to errors in the machining principle, it is called machining principle error. As long as the principle error is within the allowable range, this processing method is still feasible.

2. A few errors in the machine tool

The production errors, installation errors, and wear during use of machine tools directly affect the machining accuracy of workpieces. The main reasons for this are the rotational motion of the machine tool spindle, the linear motion of the machine tool guide rail, and errors in the machine tool transmission chain.

3. Manufacturing errors and wear of cutting tools

The production errors, installation errors, and wear during the use of CNC machining tools all affect the machining accuracy of the workpiece. During the cutting process, the cutting edge and surface of the tool collide violently with the workpiece and chips, resulting in tool wear. When the tool wear reaches a certain value, the surface roughness of the workpiece increases, and the color and shape of the chips change, accompanied by vibration. Tool wear will directly affect cutting productivity, machining quality, and cost.

4. Fixture error

The fixture errors in CNC machining include positioning errors, clamping errors, fixture installation errors, and tool alignment errors. These errors are mainly related to the manufacturing and assembly accuracy of the fixtures.
CNC machining accuracy cannot be perfect, as long as errors are controlled within a certain range, it is irrelevant. Manufacturing errors and wear of cutting tools.

5. Positioning error

Positioning errors mainly include non coincidence errors of benchmarks and inaccurate positioning sub production errors. When machining a workpiece on a machine tool, several elements on the workpiece must be selected as the positioning reference for machining. If the selected positioning reference does not coincide with the design reference (the reference used to determine a certain external scale and orientation on the part drawing), a reference misalignment error will occur. The positioning surface of the workpiece and the fixture positioning element together form a positioning pair, because the inaccurate production of the positioning pair and the large directional variation of the workpiece caused by the fitting gap between the positioning pairs are called inaccurate manufacturing errors of the positioning pair. Inaccurate positioning errors in secondary production only occur when using the adjustment method for processing, and do not occur during trial cutting processing.

6. Adjust errors

In every process of mechanical processing, adjustments must be made to the process system in one way or another. Adjustment errors occur because it is impossible to make precise adjustments. In the process system, the mutual orientation accuracy of workpieces and cutting tools on the machine tool is ensured by adjusting the machine tool, cutting tools, fixtures, or workpieces. When the original precision of machine tools, cutting tools, fixtures, and workpiece blanks meets the process requirements without considering dynamic factors, adjusting errors plays a decisive role in mechanical processing errors.

7. Measurement error

When measuring parts during or after processing, the measurement accuracy is directly affected by the measurement method, tool accuracy, workpiece, and subjective and objective factors.

The above seven mechanical processing errors can be avoided to a certain extent, so operators who need to perform mechanical processing need to carefully detect and verify these six machining processes that are prone to mechanical processing errors in all aspects before performing mechanical processing operations. This can better reduce the impact of mechanical processing errors.