Design Of Pressure Straightening Device Of Wide And Heavy Plate And Researsh On Flatening Scheme

Wide and thick plates are widely used in shipbuilding,bridge construction and other industries.In the production process,wide and thick plates will be bent to different degrees due to rolling,heat treatment and other processes,and need to be leveled before use.In cold correction,steel plates over 40 mm thick cannot be straightened on a roller straightener,and the flattening machine is required to level the steel plate.At present,in order to make the steel plate can be reversed during straightening,the worker manually places the spacer under the steel plate and between the steel plate and the indenter.The amount of pressing is also determined by the experience of the worker,and often cannot be flattened once,and needs to be repeated several times.Reverse bending can make the steel plate meet the flatness requirement.In addition,the existing flattening machine has a large indenter.The indenter is driven by a large-diameter hydraulic cylinder.Due to the size limitation,the range of the indenter is limited.Since the steel plate is wide,it needs to be moved multiple times.The indenter and the pad can level the entire plate width.This has seriously affected the straightening efficiency and accuracy of the steel sheet.Therefore,it is necessary to improve the pressure straightening efficiency and precision of the wide and thick plates.Firstly,this paper proposes a multi-point reverse bending straightening process for the existing problems of pressure and straightening of wide and heavy plates,and deduces the calculation formula of the amount of backbending based on the multi-point reverse bending straightening model.Secondly,in order to realize the multi-point reverse bending straightening process,a multi-point flexible pressure straightening device is designed.The 3D model of the device was built using SolidWorks software and the thrust of the hydraulic cylinder was calculated.The minimum values of the head and fulcrum distances corresponding to different steel plate parameters are given,and a reasonable straightening workflow is developed.Then,the finite element software ABAQUS is used to simulate the multi-pointreverse bending straightening model,and the simulation results are analyzed in depth.The theoretical calculation formula of the amount of backbending is modified by finite element method,and the modified formula is verified by experiments.Finally,the effects of various parameters on the amount of backbending in the multi-point reverse bending straightening model are studied respectively,and the formula for calculating the amount of backbending in polynomial form is fitted.Based on ABAQUS software,the straightening scheme of steel plates with different curvature types was developed.