Factors influencing the precision of machining precision parts

Machining accuracy (referred to as machining accuracy for short) refers to the degree of conformity of the actual geometric parameters of the precision parts after processing to the ideal geometric parameters. The degree of deviation between them is the processing error. The larger the processing error, the lower the processing accuracy, and vice versa. In machining, the machining error is controlled to ensure the machining accuracy of the parts. Machining accuracy includes geometric accuracy and dimensional accuracy of parts and mutual position accuracy.

    The original error that affects the machining accuracy means that during machining, each part of the process system composed of machine tools, tools, fixtures and workpieces should maintain a strict relative positional relationship during the machining process. Due to the influence of many factors, every link of the system will inevitably produce a certain offset, which will affect the accuracy of the relative position between the workpiece and the tool, thereby causing machining errors. The original error is the general term for these factors that cause deviations in the processing of precision parts. Some of the original errors depend on the initial state of the process system, and some are related to the cutting process.

    When analyzing the processing accuracy, we must pay attention to the original error in the error-sensitive direction. The following are the factors influencing the error summarized by the operator

    The main original errors related to the initial state of the process system

     1. Principle error: the error existing in the processing principle.

     2. Geometric error of process system: mainly includes manufacturing error and wear of machine tool, tool, fixture, system adjustment error, workpiece positioning error, tool installation error, etc. In fact, the principle error in cutting is also a geometric error, but it is distinguished because of its special reason.

Main original errors related to the cutting process

     1. The deformation caused by the force effect of the process system: including the force deformation of the system and the stress deformation of the workpiece.

     2. Deformation caused by the thermal effect of the process system: the deformation caused by the influence of the heat source appearing in the system work.

In addition, the temperature conditions of the environment, the measurement methods and the skill level of the workers also have an influence on the processing accuracy of precision parts processing.