Xiao Ping Zhang

Study on Short Stroke Control in Roughing Stage of Continuous Hot Strip Rolling

According to process requirements of edge rolling in roughing stage of continuous hot strip rolling, common methods of short stroke control were analyzed. A 3D elastic-plastic FEM model for roughing stage of continuous hot strip rolling was established using ABAQUS/Explicit, and research on deformation law of plate head and tailwidth lossin different working conditions was done. Besides, control effects of broken line SSC method and polynomial SSC method were analyzed. On the basis of them, a new polynomial SSC model was established. The model is effective in controlling width loss of plate head and tail and is beneficial to improve the quality of plate in some degree.

FEM Simulation of the Slab Edge Rolling in Unsteady Rolling Stage

According to characteristics of adjusting width by vertical roll at a certain steel corporation, unsteady deformation of head and tail of slab during edge rolling was analyzed by FEM simulation on base of a commercial software. The effect of several process conditions on the cross-section deformation and width loss of slab were also analyzed.

Study on Unsteady Deformation Law in Roughing Stage of Continuous Hot Strip Rolling

The vertical-horizontal rolling in roughing stage of continuous hot strip rolling is a common production technique of controlling slab width effectively. Vertical rolling will induce dog-bone, width loss and fish tail in unsteady deformation zone of slab head and tail. A 3D elastic-plastic FEM model for roughing stage of continuous hot strip rolling was established using ABAQUS/Explicit and research on the influences of those technical parameters such as slab width, slab thickness, reduction of vertical roll and horizontal roll on unsteady deformation of metal was carried out. The research work provides a scientific basis for the optimization of roughing rolling technical schedule.

Experimental Research on Hot Working Property of Monel K-500 Alloy

Monel K-500 alloy is an important nickel-based corrosion resistant material with excellent corrosion resistant ability in various corrosion circumstances (include electrochemical and chemical corrosion) and good mechanical properties. However, Monel K-500 alloy is also a sensitive material to high temperature. Hot working process has significant effect on its working character and quality. In view of existing problems in domestic manufacturing enterprises, some experiments were carried out in different working temperature, deformation degree and strain rate to investigate the performance of Monel K-500 alloy in hot working process. The research results show that moderate temperature, higher strain rate and deformation degree will be favorable to improve crystal structure and mechanical property of Monel K-500 Alloy.

Experimental Research on Heating Performance of Monel K-500 Alloy

Monel K-500 alloy is an important nickel-based corrosion resistant material with increasingly wide range of application in the areas of aviation, navigation and petroleum engineering. Comparing to other corrosion resistant metal material and nonmetal material, Monel K-500 alloy has excellent corrosion resistant ability in different corrosion circumstances (include electrochemical and chemical corrosion) and good mechanical properties. However, Monel K-500 alloy is also a sensitive material to high temperature. Its heating schedule has significant effect on heating quality and subsequent hot-working character. In view of existing heating problems of Monel K-500 alloy such as over-burning or non-uniform heating in domestic manufacturing enterprises, different heating velocities have been used to investigate its performance in heating process. The research results can provide more scientific basis for the setting up of reasonable heating schedule.

Development of a Combined Shape and Gauge Control Scheme Based on Function Φ

Combined shape and gauge control is a hot issue in continuous hot plate and strip rolling field. Due to the coupled function of shape and gauge control in rolling process, mutual effects must be considered when shape control is carried out. Traditional shape and gauge control theories are of independent and the control systems are also separated, so it is difficult to ensure the quality of shape and gauge simultaneously. Based on the shape theory of shape and gauge control and function Φ derived from the load distribution method of Ichiro Imai , a combined shape and gauge control scheme was developed, which can adjust rolling regulations on-line according to the deviation of strip crown measured at the exit of the rolling mill. The method can ensure gauge precision while strip crown is adjusted and the purpose of combined shape and gauge control is reached.

A New Approach of Combined Shape and Gauge Control

Due to the coupled function of shape and gauge control in rolling process, mutual effects must be considered when shape control or gauge control is carried out. Traditional shape and gauge control theories are of independent and the control systems are also separated, so it is difficult to ensure the quality of shape and gauge simultaneously. Based on the updated shape theory and a single parameter model of load distribution method, a combined shape and gauge control method was developed, which can adjust rolling regulations on-line according to the deviation of strip crown measured at the exit of the rolling mill. The method can ensure gauge precision while strip crown is adjusted and the purpose of combined shape and gauge control is reached.

Investigation on the Contour Curve of Straighter Roll by Conjugate Revolving Quadric Theory

Bar straightening is an important work before the bar is applied as qualified products. In this paper, the mechanics of the straightening process is analyzed in detail on the base of conjugate quadric theory. A simulation program is developed with the investigation of straightening process as well. The equations, which describe roll contour curve and the longitudinal section, are given and simulated in computer. And a brief method of designing and drawing the straightening roll contour curve is introduced.

Strip Profile Control in Asymmetrical Rolling by FEM Modeling

Asymmetrical rolling is usually used on some special rolling produce. It offers lower rolling pressure, more reduction and better crystallographic textures. In recent years asymmetrical rolling has become more important due to realization of improved properties of the strip. In this paper, a elasto-plastic finite element method code has been developed to simulate the asymmetrical rolling of strip, considering unequal roll radii, unequal speed ratio between the upper roll and lower roll, different exit thickness and different reduction. Meanwhile, The profile, crown and edge drop of strip, as well distribution of front tensile stress were discussed in different rolling process. It makes better preset values for the online control system and good results was obtained.