Numerical Calculation of High-Strength-Steel Saddle Plate Forming Suitable for Lightweight Construction of Ships

Abstract

With the demand for construction of lightweight ships and polar ships, high-strength steel is increasingly applied in shipbuilding. There are a large number of complex curved plates to be processed in ship construction. The main method for forming a complex curved plate is line heating. A saddle plate is an important type of double-curved plate, which affects the resistance performance of the ship. The existing research on high-strength-steel saddle plates is lacking. To solve the problem of forming for high-strength-steel saddle plates, the numerical calculation of line heating for a EH36 steel saddle plate was studied. By combining it with a line heating experiment of low-carbon-steel saddle plates, the feasibility of numerical calculation based on the thermal elastic–plastic theory for high-strength-steel saddle plates was verified. Under the premise that the processing conditions such as the material parameters, heat transfer parameters, and the constraint mode of the plate were correctly designed, the effects of the influencing factors on deformation of the saddle plate could be studied by the numerical calculation method. The numerical calculation model of line heating for high-strength-steel saddle plates was established, and the effects of geometric parameters and forming parameters on shrinkage and deflection were studied. This research can provide ideas for the lightweight construction of ships and provide data support for automatic processing of curved plates. It can also provide inspiration for curved plate forming in fields such as aerospace manufacturing, the automotive industry, and architecture.

Deformation Intelligent Prediction of Titanium Alloy Plate Forming Based on BP Neural Network and Sparrow Search Algorithm

“…The independence of numerical model grids is verified. The mesh size of the dense area is set to 10 mm, The calculation of the deformation field includes shrinkage and deflection, the measurement method is referred to in reference [25]. The shrinkage of low-carbon steel and titanium alloy under different grid sizes is shown in Figures 6 and 7, respectively.…”

Deflection Intelligent Prediction for High-Strength Steel Saddle Plate Forming Applicable to Reducing Ship Weight

“…In the previous research [19], a numerical calculation model for the forming of highstrength steel saddle plates has been established, and the feasibility of this model has been verified through experiments. Therefore, without special instructions, the results of deflection and temperature in the following text are obtained through a numerical calculation model.…”

“…Zhang, S. et al [18] optimized the shape parameters of the inductor in induction heating and found that the deformation of the curved plate significantly increased through optimization. Wang, S. et al [19] established a numerical calculation model for high-strength steel saddle plates through experiments and studied the influence of geometric and process parameters on the deformation of the plates. Lee, J. et al [20] derived a formula for calculating the transverse shrinkage and angular deformation of curved plates by using plate thickness, heating velocity, and heating line spacing based on the results of multi-heating line forming experiments and numerical analysis.…”

“…Deflection is an important parameter to express the overall deformation of the saddle plate. To fill the research gap in the forming of high-strength steel saddle plates, the intelligent prediction model is established in this paper based on the numerical calculation model of high-strength steel saddle plates in previous research [19]. Firstly, the influence of forming parameters and plate geometric parameters of the plate on the deflection is researched.…”