In the field of mechanical parts machining industry, there exists the concept of machining accuracy, and everyone should have an understanding of it. So today we share with you what are the process measures to improve machining accuracy!
1. Reduce the original error
This method is a basic method that is widely used in production. It is to identify the main factors that produce machining errors, and then try to eliminate or reduce these factors. For example, the turning of slender shafts, now using a large walking tool reverse turning method, basically eliminates the bending deformation caused by axial cutting force. If supplemented with a spring tip, the effect of thermal elongation caused by thermal deformation can be further eliminated.
2. Compensation of the original error
Error compensation method, is to artificially create a new error, to offset the original process system in the original error. When the original error is negative when the artificial error to take a positive value, and vice versa, to take a negative value, and try to make the two equal in size; or the use of an original error to offset another original error, but also try to make the two equal in size and opposite direction, so as to reduce the processing error, improve the processing accuracy of the purpose.
3. Transfer of the original error
Error transfer method is essentially transferring the geometric error, force deformation and thermal deformation of the process system. Error transfer method of many examples. Such as when the machine tool accuracy can not meet the requirements of the parts processing, often not just improve the machine precision, but from the process or fixture to find ways to create conditions so that the geometric error of the machine tool does not affect the machining accuracy of the aspects to transfer. Such as grinding spindle taper hole to ensure its coaxiality with the journal, not by the machine tool spindle rotation accuracy to ensure, but by the fixture to ensure. When the machine tool spindle and the workpiece with a floating linkage, the original error of the machine tool spindle is transferred away.
4. Equalization of the original error
In processing, due to the blank or the previous process error (hereinafter collectively referred to as the "original error"), often resulting in the process of processing errors, or due to changes in the material properties of the workpiece, or the process of the previous process changes (such as the blank refinement, the original cutting process cancellation), resulting in a large change in the original error. This change in the original error affects this process in two main ways.
(1). The error is reflected, causing the process error;
(2). Positioning error expansion, causing errors in this process.
To solve this problem, it is best to use the method of grouping and adjusting the mean error. The essence of this approach is to divide the original error into n groups according to their size, each group of blank error range is reduced to 1/n of the original, and then adjust the processing according to each group separately.
5. Equalize the original error
For shafts and holes with high requirements of fit accuracy, grinding process is often used. The grinding tool itself is not required to have high precision, but it can make relative movement with the workpiece in the process of micro-cutting on the workpiece, the high point is gradually ground off (of course, the mold is also part of the workpiece grinding) and finally make the workpiece to achieve high precision. This process of friction and wear between surfaces is the process of continuous reduction of errors. This is the error equalization method. The essence of it is the use of closely linked surfaces to compare with each other, check each other to find out the differences from the comparison, and then carry out mutual correction or mutual benchmark processing, so that the workpiece is processed surface error constantly reduced and even. In production, many precision benchmark parts (such as flat, straight, angle gauge, end teeth indexing disc, etc.) are processed using the error equalization method.
6. In-situ processing method
In the processing and assembly of some precision problems, involving the interrelationship between the parts or components, quite complex, if you focus on improving the accuracy of the parts themselves, sometimes not only difficult, or even impossible, if the use of in situ processing method (also known as their own processing repair method) method, it may be very convenient to solve the seemingly very difficult accuracy problems. In-situ machining method is commonly used in the machining of mechanical parts as an effective measure to ensure the accuracy of parts processing.
