The precision machining industry is the pillar industry of the national economy and has very promising prospects. When processing precision mechanical parts, the processing plant will have many requirements and rules for the processing technology to ensure the pass rate of the factory parts.
So do you know what are the factors that affect precision machining? Let's take a look!Precision machining technology was proposed in the 1960s. It is an important way to improve the performance, quality, service life and reliability of electromechanical products, and the cross-section of bars can be an important method. Fine machining means that the machining error is less than 0.1 m, the surface roughness is less than RA0.025IXM processing technology, also known as sub-micron processing. The degree of fine parts processing is an important indicator of the degree of national manufacturing.
In addition to the shaking of hydraulic and pneumatic sources in precision machining, the working environment has a great influence on the processing quality. Therefore, the working environment is a necessary condition to ensure the processing quality. The working environment mainly requires temperature, purification and anti-vibration requirements. The environmental temperature change has a particularly significant impact on the accuracy of the machine tool, including the temperature change of the thermal element caused by the machining error. The dust of the total machining error (40 70)% will cause the surface of the workpiece to be scratched and affect the appearance quality. Vibration, stripes or fabric traces have been processed on the surface of the workpiece, and the surface brightness is significantly reduced.
With the high precision of parts processing requirements, the requirements for the processing environment are becoming more and more severe, only from the analysis of the impact of precision machining on gas pressure fluctuations, environmental temperature changes, external and natural vibration, and the analysis of fine parts processing elements There are many influences. In order to improve the precision of ultra-fine processing, it is not only necessary to understand the influence of the elements, but also to control the processing plan. The quality of fine parts processing is expressed by the accuracy of processing.
1. The interchangeability of parts
According to precision machining manufacturers, after long-term consumption and operation of the machine, some parts will inevitably be worn, deformed and scrapped. Replace with new parts. These parts are called accessories or spare parts. Fittings or spare parts can be installed on the machine without repair or selection, which is called interchangeability.
In order to achieve interchangeability, when manufacturing parts, the dimensions and geometric shapes of the parts must be made different. The so-called divergence is not to request that the score is not bad (this is neither economical nor possible). It is only necessary to control the size and geometric shape of the part within an allowable range, so that the part and other parts have the same The separation performance will do. The allowable error range is the form and position tolerance.
2. The quality of precision machining is expressed by machining accuracy
1.Geometry accuracy
The accuracy of geometric shape refers to the precise level of geometric shapes such as the appearance or axis of the component parts, such as whether the line can be straight, the surface can be flat, and the cross section of the cylinder can be round. The allowable range of variation is represented by "shape and position tolerance". The smaller the shape and position tolerance number, the higher the shape accuracy.
2. Dimensional accuracy
According to the analysis of precision machining manufacturers, dimensional accuracy refers to the accurate level of the dimensions of the parts after processing, which is expressed by "dimension tolerance". When the dimensions of the parts are the same, the higher the accuracy, the smaller the tolerance number.
3. Position accuracy
According to the manufacturer of fine parts, the position accuracy refers to the precise level of the mutual position of the various appearances of the components, such as whether two planes are parallel, vertical, and coaxial, etc., expressed by "position tolerance".
The above-mentioned shape and position tolerances are referred to as "shape and position tolerances".
