1. The bearing pad is pressed into shape
The bearing pad was originally pressed and formed on a mechanical hydraulic press with a pressure of 110t and a workpiece tolerance of 0.02mm. Due to the drift of the bottom dead center position of the slider, it is often out of tolerance periodically; after the servo hydraulic press is used, the speed of the slider can be strictly controlled. And displacement, control the position of the slider at the bottom dead center, the actual deviation of the workpiece can be controlled within 0.01mm, but the load can be reduced by half, only 48t.
2. Optimal speed punching
For SPCC steel plate blanking parts, the best blanking speed is about 9mm/s. By setting the slider stroke of crank, six-bar and eight-bar hydraulic presses to 1200mm, and the number of continuous strokes to 18 times/min, analysis of its motion characteristics shows that the working speeds of hydraulic presses with different transmission rod systems are also different. The punching start point is 3mm from the bottom dead center, and its working speeds are 133.7mm/s, 118.5mm/s, 95.6mm/s, which are much higher than the best punching speed (that is, using traditional mechanical hydraulic presses, in It is difficult to achieve the best punching speed under the premise of ensuring the production cycle. However, the servo hydraulic press is used to achieve the best punching speed by rapidly reducing the speed of the servo motor before the punching point is reached.
3. Automobile panel production line
Japan's Amino Corporation has developed and produced large-scale mechanical multi-link servo hydraulic presses, which are well used in China. Currently, companies that have introduced such hydraulic presses include Dongfeng Motor Co., Ltd., Tianjin Automobile Mould Manufacturing Company, Chengdu Aircraft Manufacturing Company, and Guangzhou Hino Motor Company and Hubei Pioneer Mould Company, etc. Among them, Dongfeng Motor Company introduced a panel production line composed of one 10000kN and four 6000kN mechanical multi-link servo hydraulic presses in 2007. This production line undertakes the production tasks of small and medium-sized stamping parts for the body-in-white of Dongfeng Xiaobawang series, Dongfeng Star series, Dongfeng Dream Card series and other models. The main processes include blanking, drawing, trimming, punching, beveling, correction and crimping, etc. After actual processing and production verification, this series of servo hydraulic press has significantly improved the production efficiency of the production line, achieved a major breakthrough, and has the advantages of energy saving, low noise, high productivity, and controllable production process management.
4. Magnesium alloy extrusion forming
It is difficult to form magnesium alloy materials on ordinary crank hydraulic presses. Japan's Komatsu successfully realized the reverse extrusion forming of magnesium alloy cup-shaped parts on the HCP3000 servo hydraulic press developed by it. First put the blank into the concave mold, the convex mold descends slowly, and press the blank between the punch and the ejector. During the descending process, the blank is heated to 300°C; when the ejector reaches the lower limit position, it slides. The block descends at a constant pressure and a low speed, and the extrusion process is started until the back extrusion process is completed; then the slider quickly returns. The slider has experienced four different speeds in one cycle, and the constant pressure controls the extrusion process. This process puts forward high requirements for speed control, which is difficult to achieve on ordinary crank hydraulic presses.
5. Low noise blanking
When the blanking process is carried out on an ordinary mechanical hydraulic press, due to the sudden fracture of the material, large vibration and noise will be generated, which will not only affect the processing quality of the parts, but also cause noise pollution and endanger the health of workers. If the movement speed of the slider can be effectively controlled so that the stored variable properties of the part during the deformation process are basically released before the material is completely broken, it will be possible to greatly reduce the vibration and reduce the noise.
6. Fine blanking
A comparison test of precision blanking was carried out on the ordinary mechanical hydraulic press and the HAF servo hydraulic press. The workpiece was an air conditioner cam, the size was 40mm×13mm, the load was 80t, and the material was SPC. The lower the punching speed, the greater the thickness of the cutting section and the better the section quality. Cracks will appear on the surface of the ordinary hydraulic press after 2,000 to 3,000 pieces, but the cross-section of the servo hydraulic press remains intact after 3,000 pieces.
