In order to improve the quality of precision machining, to identify the main factors causing processing errors (original error) is the key, however, how to take the appropriate process technology measures to control or reduce the impact of these factors? The following editor will work with you to understand how to effectively improve the quality of precision machining six methods.
First, error grouping method
This method reported gross bad or the previous process processing work size is measured according to the size of the error into n groups, each group of workpiece size error range is reduced to the original indeed / n; and then according to the error range of each group respectively adjust the position of the tool relative to the workpiece, so that the name group of workpiece size dispersion range center is basically the same. So that the size dispersion range of the whole batch of workpiece is greatly reduced. This method is often more economical and easy to use than to improve the vigilance of the gross bad precision snow. Such as in the finishing tooth shape, in order to ensure that the coaxiality of the gear ring and gear bore after processing, should reduce the gear inside also with the mandrel of the fit clearance. In the production is often grouped according to the size of the gear inside also, and then with the corresponding grouping mandrel, which evenly divided the original error due to the gap, improve the position of the gear ring accuracy of vigilance.
Second, the error compensation method
This method is to artificially create a new original error, support offset the original process system inherent in the original error, so as to achieve the purpose of reducing the processing error, processing accuracy.
Third, the error transfer method
This method is essentially the geometric error of the process system, force deformation and thermal deformation, etc. to transfer to the direction that does not affect the machining accuracy. For example, for multi-station processes with indexing or indexing or processes using indexing tool holders, the indexing and indexing errors will directly affect the machining accuracy of the relevant surface of the part.
Fourth, the error equalization method
This method uses closely linked surfaces to each other, mutual correction, or use each other as a benchmark for processing. It can make those local larger error more uniformly affected the entire processing surface, so that the processing error transmitted to the surface of the workpiece is more uniform, and thus the workpiece processing accuracy is greatly improved accordingly.
Five, in situ processing method
In the processing and equipment with some precision involved in the interrelationship between parts, quite complex. If you focus on improving the precision of the parts themselves, sometimes not only difficult or even impossible, and the use of in situ processing hair can solve this problem. The main point of in-situ machining hair: to ensure what kind of position relationship between the parts, on such a position relationship using a part mounted on a tool to process a part. For example, in the manufacture of hexagonal lathes, the axis of the six large holes on the turret mounted tool holder must ensure that the machine tool and spindle rotation line overlap, the end face of the large holes and must be perpendicular to the spindle rotation line.
Six, direct error reduction method
This method is widely used in the production of a basic method. The method is to identify the main original error factors affecting machining accuracy, and then try to eliminate or reduce it directly. For example, the turning of long and thin shafts, due to the force and heat, causes the work to bend and deform. Now the "big straight tool reverse cutting method" is adopted, which basically eliminates the bending caused by cutting force. Supplemented by a spring tip, the harm of thermal elongation can be further eliminated.
