Do you know the precautions in the process of waterjet cutting compensation?

When the waterjet cutting machine is cutting, the trajectory of the cutting path according to the CNC command is the theoretical size. The actual cutting size will have a slight offset. This is because there is a slit during cutting, and the slit is the part that is lost during cutting. If the geometric size compensation is not performed, the actual cut part size will be smaller in the length direction of the outer contour part and the inner contour size will be larger (the two sides are just the difference between the slit width and the one side is half the slit) For example, we want to cut a φ100mm For a round workpiece, the diameter of the water beam is φ1m, then the cutting path of the waterjet is cut according to a circular path with a diameter of φ101mm (the cutting motion path is the path that the center of the water beam is cut through, G generated in the CAD / CAM software The motion coordinates indicated by the code are the coordinates of the cutting trajectory), not a circle of φ100mm. If the motion trajectory is φ100mm, the diameter of the final cut workpiece is only φ99mm, and the circumference is smaller than the required φ100mm by a cutting radius (ie The radius of the cutting water beam). In order to compensate for the missing cutting radius, the CAD / CAM software needs to add a cutting radius to the movement path based on the size of the workpiece (if it is a cutting hole, it should subtract one cutting radius), which is called radius compensation. In order to finally be able to process the processed parts with the required size.
 
Pay attention to the following points when setting slit compensation:
1. After the software compensation is set, there is generally no need to compensate on the numerical control system, otherwise the compensation repeat size will be deviated again. But if the software compensation is still a little bit smaller after cutting, it can be compensated through the CNC system.

2. If the compensation is done by CNC system, the compensation amount should be set to zero in the software.

3. If you are not sure how much size should be compensated, you can cut a rectangle on the waste, measure the actual size and the programmed size to calculate the required compensation.

4. The CNC system is more difficult to handle the compensation of small arcs. If the arc is smaller than the compensation radius, it cannot be cut, and it cannot be compensated correctly (theoretically, the radius becomes a negative number). In this case, you should consider modifying the parts. Figure, or consider using software compensation to find problems in time.