Rotary Rolling Mill Research Articles

Improving the Design of a Ø120-mm Mandrel for Piercing Semifinished Products in a Two-High Rotary Rolling Mill

The design of a O120-mm piercing mandrel is optimized for use on a two-high rotary rolling mill with mushroom-shaped rolls and Diescher guide discs. A numerical model of the piercing operation is constructed as well.

Modeling the Piercing of Semifinished Products in a Three-Roll Rotary Rolling Mill on a Hollow Mandrel

The piercing of a tubular semifinished product by a hollow mandrel in a three-roll rotary rolling mill is modeled on a computer in the software DEFORM 3D. An analysis of the results showed the advantages of using a hollow mandrel instead of the traditional solid mandrel when a continuous-cast semifinished product is being pierced. Use of the hollow mandrel can alleviate variations in the thickness of the wall of the resulting hollow semifinished products.

Evaluating the Adequacy of a Mathematical Model of the Piercing of a Billet Into an Ultra-Thick-Walled Shell on a Two-High Rotary Rolling Mill

A physical experiment involving the piercing of a billet into an ultra-thick-walled shell is carried out on two-high mill 130D at the Moscow State Institute of Steel and Alloys. With the same process parameters as in the experiment, a mathematical model of the piercing operation is constructed by using the finite-element computing system in the software Deform 3D. The degree of agreement between the mathematical model and the physical experiment is evaluated on the basis of such indices as the geometric parameters of the pierced shell, the helix angle, and one of the kinematic characteristics ‐ the time that elapses from the moment the billet contacts the rolls to the moment it contacts the mandrel.

Mini tube-production unit 40–80 with a three-high reeling mill

A new mini tube-production unit has been placed in service at the Sechang Steel Co., Ltd (in South Korea) to make seamless tubes ranging in diameter from 40 to 80 mm. The production process is based on the piercing of a semifinished product, reeling of the resulting shell on a rotary rolling mill to obtain a rough tube, and sizing of this tube on another rotary rolling mill. The technology was developed in the Department of Tube-Production Technology and Equipment at the Moscow State Institute of Steel and Alloys (MISiS).

Small mill for the high-temperature rotary rolling of semifinished products composed of refractory metals in protective media

A description is presented of a small vacuum-type rotary rolling mill designed for the high-temperature deformation of semifinished products to obtain bars 7‐10 mm in diameter. It is shown that the CAD software Autodesk Inventor is an effective means of performing a virtual study of a parametric 3D-model of the mill to evaluate its strength and stiffness.

Calculation of the geometric parameters of rotary rolling by using the automated design system autodesk inventor

A method is proposed for calculating the profile of the rolls of a rotary rolling mill with the use of the 3D-modeling program Autodesk Inventor. The universality of the method is shown for calculating the geometry of rotary rolling within broad ranges of values for the parameters that characterize the mutual position of the axes of the rolls and the semifinished product being rolled.

Study of the temperature regimes in the heating and piercing of steel ingots to obtain thick-walled shells

This article examines aspects of the use of thermal imaging and mathematical modeling to determine temperature inside a semifinished product as it is heated and pierced on a rotary rolling mill. A scheme is devised to thoroughly examine the thermal state of metal during shaping operations, and thermograms are obtained of the surface of metal at different moments in the piercing operation.

Determining the adjustment of piercing mills with driven guide disks (Disher mills)

A method is proposed for determining the basic adjustment for piercing on a rotary rolling mill with driven guide disks. Formulas are derived for the distance between the guide disks as a function of the piercing conditions.

Effect of the main parameters of helical rolling on the ductility properties of hypereutectic silumin alloys

The author examines how the number of cycles in which the work rolls of a rotary rolling mill load semifinished products made of hypereutectic silumin alloys depends mathematically on the degree of deformation e and feed angle in three-roll rotary rolling. Another mathematical model is proposed to describe the dependence of the dispersity (dimensions) of the silicon crystals (one of the two phases in the structure of hypereutectic silumins that adversely affects the ductility properties of these alloys) on the number of load cycles Nc, the feed angle α, and the deformation e. The proposed models adequately describe the experimental data, differing from the latter by no more than 5–7% and remaining within the permissible error.

Aspects of the piercing of shells made of hypereutectoid silumins on a universal 20–60 rotary rolling mill

The world’s first technology has been introduced for piecing hollows (tubes) of hard-to-deform hypereutectic silumin alloys (01390 and 01392). The tubes have the dimensions 80 mm diameter × 13.5 mm wall thickness and 74 mm diameter × 15 mm wall thickness. The are obtained on universal rotary rolling mill 20–60. The technology was developed by modeling the rotary rolling operation, studying the rheological properties of hypereutectic alloys, finding scientifically sound parameters (rolling scheme, feed angles, temperature-speed parameters) for an intermediate rotary-rolling operation performed to obtain bars with a crystalline structure and ductility properties 3–4 times better than those of the initial ingots, and the developing and introducing a piercing process that employs special spherical mandrels with a conical nose.

Method of Calculating the Gaps between the Rolls of a Rotary Rolling Mill

Method of Calculating the Gaps between the Rolls of a Rotary Rolling Mill

Reduce Rolling Characteristics of Hollow Piece by Rotary Rolling Mill.

Extra-thick-walled tubes, hollow rods, in which wall thickness to outside diameter ratio is 25% or more, are produced at steel rod rolling mills at large, as they cannot be manufactured into seamless tubes at any existing mill plant. They are currently produced by a process in which a square billet with an inserted mandrel of manganese steel is passed through a bar mill. Then, the hollow billet is finished to the desired diameter and wall thickness. After that, the mandrel is removed from the hollow billet. The unit tool requirement of this process is costly and uneconomical, and the dimensionally accuracy is low. In this paper, the reduce rolling characteristics of hollow piece by rotary rolling mill have been studied in detail. This process, in which a rotary rolling mill with three rolls has been used for reducing the outside diameter of hollow piece, makes it possible both to obtain hollow rods with high dimensional accuracy and to produce hollow rods efficiently. This rotary rolling makes it possible to reduce the outside diameter of hollow pieces and to control the wall thickness of hollow pieces with no internal sizing tool by only setting rotary rolling mill conditions. Hollow pieces having the desired dimensions can be produced with high accuracy.

Device to count semifinished products in the line breakdown stand of a rotary rolling mill

Device to count semifinished products in the line breakdown stand of a rotary rolling mill