Development of a Method for the Evaluation of the Gap in the Course of Straightening of Sheet Products on Roller Leveling Machines

It is shown that there are two basic types of design of roller leveling machines (RLM) according to the principle of adjustment of the gap between the rollers, namely, with parallel and inclined arrangement of the rollers. We present the dependences for the numerical analyses of the curvature of reverse bend and the adjustment gap for the RLM both with horizontal and inclined positions of the rollers. It is demonstrated that, in the case of straightening performed in an RLM with horizontal arrangement of the rollers, the gap decreases from 38.8 to 7.8 mm as the thickness of the sheet made of 10KhSND steel decreases from 40 to 12 mm. For the sheet made of 10G2S1D steel, it decreases from 38.6 to 7.2 mm and for the sheet made of 14Kh2GMR steel from 38.6 to 6.2 mm. In the case of straightening carried out in an RLM with inclined arrangement of the rollers for a sheet made of 10KhSND steel with a thickness of 20 mm, the minimal gap constitutes C_min = 19.6 mm, while the maximal gap C_max = 20.0 mm. Moreover, for 10G2S1D steel, we get C_min = 19.5 mm and C_max = 20.0 mm. Finally, for 12G2MFT steel, we find C_min = 19.3 mm and C_max = 19.9 mm. We performed the experimental straightening of sheets of 10 steel 16 mm in thickness and 2400 mm in width on a seven-roller RLM (produced by Severstal’). The comparison of the experimental value of gap C_exp = 13.1 with its theoretical value C_calc = 12.8 mm shows that difference between these values is equal to 4.5%.