Abstract：In the actual production process,the straightening efficiency and straightening accuracy of high-strength thick plates are low due to the lack of advanced straightening equipment and straightening technology. The traditional pressure straightening is based on the three-point back-bending straightening theory. The steel plate is supported by two fulcrums. In the middle,a large hydraulic cylinder is used to straighten. In the whole process,it mainly relies on manual operation. However,the error is quite large and the operation is more complicated. Many factories rely on their usual accumulated experience when determining the amount of back bending. It is also necessary to improve the analytical expression of the back bending. Therefore,we should study the straightening process of high-strength thick plates for improving the straightening efficiency and straightening accuracy of high-strength thick plates. This paper studies the craft of multi-point flexible pressure straightening of high-strength thick plates. First,in the straightening process,the main process parameters are determined by the straightening theory. The large hydraulic cylinder is discretized. Besides,multiple indenters and fulcrums are adopted to reduce the unstraightened area of the plate. Then,through the relationship between the bending moment,corner and the deflection in the straightening process,we can derive the analytical formula of the reduction. The back bending calculated by the formula is simulated in Abaqus. We can carry out sets of simulations by controling variables. The reliability of the formula is confirmed by studying the parameters such as the thickness of the plate,the distance between the fulcrums and the material properties in the multi-point flexible pressure straightening. Finally,we carry out experiments on the self-designed multi-point flexible pressure straightening device. It is verified that the static pressure delay strategy can reduce the residual deflection of the plate during the straightening process. At the same time,it is determined the feasibility of the craft by comparing the experimental results.
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2022, Vol. 57 
