Factor 3: Process and operation
The processing of shearing machine has its precision range, you should select the processing method reasonably and economically according to your own requirements.
Shearing positioning method:
The positioning methods of guillotine metal shears mainly include back gauge cutting method and line cutting method.
Due to the need for visual measurement of the positioning of linear shear accessories, line cutting accuracy is obviously not as good as that of relying on the back gauge mechanism.
So the special-shaped work parts, large parts, and tails all require guillotine shear back gauge cutting.
Especially for thick plate and large plate, it is difficult to fine tune and position the liner shear because of its heavy weight. To prevent poor machining accuracy, users need to be very careful or customize special positioning device during operation.
Movement and deformation of plates:
Plate cutting is an extremely complex process. For sheet metal parts, it is difficult to avoid the edge and section defects and deformation. It mainly includes section slope, bed surface uplift and shear edge deformation.
Also, the plate may move randomly because of the factors such as too large shear force required by thick plate, less presser foot on parts, and failure of presser foot. This will all lead to shearing parallelism error, thus affecting the size of the part.
As we all know, manual operation has a great influence on the accuracy of plate shears. Therefore, customers should standardize the operation in production and strengthen the inspection of accessories.
In addition, the impact and vibration during the positioning of the back gauge, the droop effect caused by the large shear width (large gravity), positioning error of manual measurement and so on. Above all have an impact on the cutting accuracy.
2. How to improve guillotine shearing accuracy?
Standard blade installation and adjustment
– The installation is firm without looseness.
– The joints of the upper and lower blades must be flush. That is, the entire blade mechanism maintains a straight line.
– Adjust the gap to make it uniform and stable.
– Before working, the user should adjust the shearing clearance according to the thickness of the plate.
– Master the turning time of the blade. If there is not too much damage, it can be used again after polishing.
– Whether it is a new edge or a polished edge, should be installed, adjusted and used according to the specifications.
These measures can not only improve the working speed and quality, but also greatly reduce the damage degree and frequency.
Operation and maintenance of guillotine shears
Correct use of sheet metal guillotine shearing machine can achieve normal cutting accuracy. Wrong operation will not only lead to poor machining accuracy, but also cause safety accidents and machine failures.
– Work in accordance with official operation manual of guillotine shears.
– Prohibit all non-standard operation! Do not cut sheets that exceed the specified thickness and multi-layer stacked sheets.
– Make sure that the equipment works well, especially the tool holder, eccentric sleeve and other key parts.
– Check the adjustment of blade clearance regularly. Solve the problems in time when found.
– It is necessary to change the blade regularly and maintain the machine.
Different plates use different blades
– When the hardness of the plate increases, the manufacturer should increase the edge strength to meet the production needs.
– At the same time, we should also consider increasing the strength of the cutting blade according to the material of the plate, so as to reduce the wear degree and frequency.
Error control and correction
Plate processing can not completely avoid any deformation and movement, which will lead to errors. Inconsistent deformations make dimensional tolerances.
In production, we should put thick or large plate in the position where there are more presser feet and the pressure foot force is relatively stable to obtain better dimensional accuracy.
Accurate measurement of data is essential for precision. We should pay attention to observation, comprehensive analysis and calculation.
Please measure two or three positions to reflect the sheet size correctly. Analyze the effect of cross-sectional tilt to avoid defects such as boss, end plate, and excessive burrs.
The system of CNC guillotine metal shearing machines can automatically calculate and compensate the cutting angle by inputting sheet data to improve the accuracy.
CNC system controls the cutting angle and stroke with linear encoder feedback data. The computer stores the corresponding list of shear angle and blade clearance with material. So, that can control the adjustment of blade clearance to improve the cutting precision.
At the same time, we can also increase the configuration to improve the cutting accuracy and quality. For example, add the following devices: anti-twist device, sheet supporting device and front feeding device…