Operation skills of seam compensation for waterjet cutting machine

When cutting with a waterjet cutter, the trajectory of the cutting path according to the numerical control instructions is the theoretical size.The actual cutting size will be slightly offset. This is because there is a slit during cutting, and the slit is the part lost during cutting. If the geometric dimension compensation is not performed, the length of the outer contour of the part actually cut will become smaller in the length direction and the inner contour size will be larger (the width of the two sides is exactly different from the width of the slit, and the width of one side is half of the width of the slit).
For example, if we want to cut a circular workpiece with a diameter of 100mm and a water beam diameter of φ1m, then the cutting trajectory of the waterjet is cut according to a circular trajectory with a diameter of φ101mm (the cutting motion trajectory is the path traveled by the center of the cutting water beam, CAD (The motion coordinates indicated by the G code generated in the / CAM software are the coordinates of the cutting motion trajectory), not a circle of φ100mm: if the motion trajectory is φ100mm, the diameter of the final cut workpiece is only φ99mm, and the peripheral ratio is less than the required φ100mm A smaller cutting radius (the radius of the cutting water beam). In order to compensate for this missing cutting radius, the CAD / CAM software needs to add a cutting radius based on the workpiece size (if it is a cutting hole, You should subtract a cutting radius), which is the so-called radius compensation, so that the final machined part can be processed in accordance with the required size.

Pay attention to the following points when setting the slit compensation:

1. After the software compensation is set, it is generally not necessary to compensate on the CNC system, otherwise the compensation repeat size will be biased again, but if the software compensation is still a bit smaller after cutting, it can be recompensated by the CNC system.

2. If it is compensated by the 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 material, measure the actual size and the programmed size to calculate the required compensation amount.

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 negative). In this case, you should consider modifying the part. Map, or consider using software compensation to detect problems in a timely manner.