Papers by Keyword: Feed Angle

Abstract: In this paper the task of the study of the deformation during helical piercing of the metal was set and solved with the use of the DEFORM-3D software. Methodology, that allows to calculate the length of helix lead along the deformation zone, as well as determine for each lead absolute and relative reduction, the width of the contact area and the metal strain refinement indicator was developed. Based on the developed methodology application the following variation regularities were established: helix lead length (l_i), quotient reduction (Δr/r₀), ratio of the billet radius to the width of the contact area (r₀/b), as well as the length of the billet contact surface (l₀) with the roll in dependence of the feed angle (β), the roll number of revolutions (N) and the plug nose advancement over the gorge (C_g).

Abstract: Drill steel is a special steel specifically tailored for drilling rods. To understand the microstructure properties and dimensional accuracy of the drill steel, a rigid plastic finite element method was used to analysis Mannesmann piercing in steel drilling production. The three-dimensional thermal force coupling FEM models were computer generated with different feed angle. The metal deformation during the piercing process was analyzed in detail. The influence of feed angle on deformation, force, velocity and strain was obtained through simulations.

Abstract: Feed angle have a great effect on the flotation efficiency of self-priming centrifugal flotation cell.In order to improve the efficiency of flotation,the effect of feed angle on the flow field in a self-priming centrifugal flotation cell was investigated using STAR CCM+.The distribution law of velocity,pressure,turbulent kinetic energy under different angles was gotten.The turbulent kinetic energy and the pressure difference increased with the feed angle. Result shows that the feed angle acting on the interior flow field is significant and the feed angle of 20º is more conducive to flotation than others.Conclusion can provide a theoretical foundation for improving flotation efficiency and optimizing flotation structure.

Abstract: This paper deals with prediction of improvement in surface roughness in helical scan grinding by simulation of virtual ground surface with a 3D-CAD model. It has been found that, by choosing the value of parameters of several grit conditions such as grit arrangement, protrusion height, inclination angle and so on, randomly for a real wheel, the maximum unevenness of the virtual ground surface and tendency of its change with feed angle nearly coincide with the surface roughness in the experiment of helical scan grinding. It is found that this simulation method is effective for the prediction of a surface ground by helical scan grinding.

Abstract: This paper deals with prediction of improvement in surface roughness in helical scan grinding by simulation of virtual ground surface with a 3D-CAD model. It has been found that, by choosing the value of parameters of four grit conditions such as grit arrangement, protrusion height, apex angle and inclination angle randomly to a real wheel, the maximum unevenness of the virtual ground surface and tendency of its change with feed angle nearly coincide with the surface roughness in the experiment of helical scan grinding. Furthermore, it is demonstrated that this analyzing method can be applied to R-shaped groove grinding and suggested that helical scan grinding is effective in grinding bearing grooves.

Abstract: Estimation of mechanism of surface finish improvement in helical scan grinding, a method in which a good surface finish is obtained besides keeping a high grinding efficiency, is performed based on the virtual grinding trace using a 3D-CAD model. In three grit models, (a) a single grit on a wheel, (b) plural grits arrangement on a helical line on the wheel circumference, and (c) multiple grit arrangement in a triangular pattern, virtual grinding traces and their unevenness or surface roughness are investigated. The virtual grinding trace in helical scan grinding is made by interference of grit trajectories, and the results of the analysis are very similar to experimental results.