Technical Parameters Prediction Of Line-Heating Process For Analogue Spherical Hull Surface

For a long time, the double-curved hull plate forming in shipyards depends on skilled workers performing the line-heating process by their empirical intuition and handwork. With the development of modern shipbuilding technique and the transformation of shipbuilding mode, the manual and experiential technique pattern of line-heating can not meet the requirement of modern shipbuilding in processing speed and product quality, leading to the innovation of the line-heating technique in the last twenty years. At present, the research on line-heating process is mainly concerned in the field of small curvature and large-scaled curved plates, including amidships plates and bow plates and stem plates. Because of its small curvature and large size, heating lines spacing is far apart, thus, proper simplification is adopted in the study, ignoring some minor factors, getting a good result that can reach the requirements of production. Compared with these plates, the analogue spherical hull surface (The surface that near to bow and stem, that is similar to spherical surface or ellipsoidal surface is defined as analogue spherical hull surface)has the characteristics of little size and big curvature, it is harder to be formed, and there is few research on this field.In this paper, analogue spherical hull surface plate is expressed by cubic non-uniform B-spline curve, and then, meshing the surface in a radial method, presenting the radial expression method. And then researching a new method of calculating the intersection of flat surface and curve surface, based on meeting the requirement of calculation accuracy, the calculation is simple and will not produce accumulative error. After finishing the expression, locating the heating line and calculating the amount of shrinkage of the heating line is done, at last, the paper gives a report about the arrangement of the heating line.This paper develops a module named Technique Parameters Of Line-Heating Process For Analogue Spherical Hull Surface based on Windows XP and Auto CAD and with the help of VC++6.0, thus realizing these functions such as surface fitting, curved surface intersection meshing the surface, expression of surfaces, locating the heating line, calculating contraction of the heating lines, it's available for line heating process.