It is because of the importance of the positioning benchmark in the processing center operation process, so we must be careful to choose, effectively follow the loading and unloading parts convenient, simple size operation, ensure the processing accuracy of the principle, some of the selection skills, also need to master the operator.
One, as far as possible to choose parts design datum for positioning datum
The so-called design benchmark refers to the benchmark used in the design drawing. The selection of design benchmark is the positioning benchmark, which avoids the positioning error at the same time, but also ensures the machining accuracy of the parts, without repeated preparation and improve the processing efficiency.
Two, when it is not possible to complete the position processing including positioning datum and design datum at the same time, try to make it coincide
If the equipment is unable to carry out processing operations including positioning datum and design datum at the same time, it can choose the datum points which coincide with each other as far as possible, and meet the requirements of completing all the key parts processing with one clamping to avoid the damage of the workpiece caused by several non-important size processing.
Three, try to choose to complete multiple processing tasks of the reference point
When selecting the reference point, the positioning method of each machining surface of the parts is taken into full consideration. One positioning can complete multiple processing contents as far as possible, improve the processing efficiency and reduce the processing cost.
Fourthly, there is a certain geometric relationship between the origin of the workpiece coordinate system and the positioning datum
The origin of the workpiece coordinate system is the "programming origin" setting the main consideration is to facilitate programming and measurement, so the positioning reference does not need to fully coincide with it, but in order to complete the high precision requirements of the processing of the workpiece, in determining the positioning reference, or to consider whether the origin can be accurately measured through the positioning reference.
In the parts processing technology, whether it is the beginning of the crude benchmark, or the fine benchmark in the process, should ensure the stability and reliability of the positioning benchmark, while taking into account the fixture structure is simple, workpiece loading and unloading conditions, so as to better complete the processing task.