US3869895A

US3869895A - Arrangement for forming solids of rotation by a cross wedge rolling process with three rolls

Info

Publication number: US3869895A
Application number: US460168A
Authority: US
Inventors: Jiri Holub
Original assignee: VYZKUMNYUSTAV TVARECICH STREJU A TECHNOLOGIE TVARENI
Current assignee: VYZKUMNY USTAV TVARECICH STREJU A TECHNOLOGIE TVARENI; VYZKUMNYUSTAV TVARECICH STREJU A TECHNOLOGIE TVARENI
Priority date: 1973-04-13
Filing date: 1974-04-11
Publication date: 1975-03-11
Anticipated expiration: 1992-03-11
Also published as: CS171399B1; JPS5068942A; DE2415805A1; GB1432899A

Abstract

A rolling mill with three cylinders, supporting exchangeable wedge shaped forming bodies for cross wedge rolling of solids of rotation is provided with forming bodies having forming ledges and triangular cavities, enabling the external parts of one forming body to enter the cavity of an adjacent forming body so that the forming ledges may for rolling of objects of a small diameter come close to the axis of the rolled object.

Description

United States Patent [191 Holub [451 Mar. 11, 1975 1 ARRANGEMENT FOR FORMING SOLIDS OF ROTATION BY A CROSS WEDGE ROLLING PROCESS WITH THREE ROLLS [75] Inventor: JiriHolub,Prague,Czechoslovakia 73] Assignee: Vyzkumny ustav tvarecich streju a technologie tvareni, Brno, Czechoslovakia [22] Filed: Apr. 11, 1974 [21] Appl. No.: 460,168

[30] Foreign Application Priority Data Aprv 13, 1973 Czechoslovakia 2635-73 [52] US. Cl. 72/107 [51] Int. Cl. B2lh 8/02 [58] Field of Search 72/71, 107

[56] References Cited UNITED STATES PATENTS 412,626 10/1889 Jones 72/107 1,493,836 5/1924 Wurster 72/107 Primary Examiner-Lowell A. Larson [57] ABSTRACT A rolling mill with three cylinders, supporting exchangeable wedge shaped forming bodies for cross wedge rolling of solids of rotation is provided with forming bodies having forming ledges and triangular cavities, enabling the external parts of one forming body to enter the cavity of an adjacent forming body so that the forming ledges may for rolling of objects of a small diameter come close to the axis of the rolled object.

1 Claim, 7 Drawing Figures ARRANGEMENT FOR FORMING SOLIDS OF ROTATION BY A CROSS WEDGE ROLLING PROCESS WITH THREE ROLLS BACKGROUND OF THE INVENTION This invention relates to an arrangement for forming solids of rotation by a cross wedge rolling process with three rolls and with exchangeable wedge shaped forming bodies.

The forming of round or mutliedged objects by a cross wedge hot rolling process is performed by two or three rolls with wedge shaped tools, fixed or provided on said rolls. A twin roll rolling mill is capable of rolling one size of rolls products within the range of their size and within a large range of diameters and lengths. Three roll rolling mills are however in this respect limited both regarding rolled diameters and rolled lengths. The maximum diameters of three rolls and of the tools are limited by the capability of rolling the object of required diameter without a danger that the tools are making mutual contact. It is impossible to roll on actual three roll rolling mills products of small diameters with currently used tools of a large diameter and vice versa, i.e. with tools of small diameter to roll products of larger diameters, in the latter case due to lack of strength of the rolling device. Tools of a small diameter have a small circumference and consequently are capa ble of rolling short lengths only.

SUMMARY OF THE INVENTION It is an object of this invention to remove these drawbacks and to provide a rolling mill with three rolls arranged symmetrically with respect to the axis of the rolled object, supporting exchangeable forming tools and rotating in the same direction, capable of rolling solids of rotation having a relatively wide range of diameters and with lengths which are approximately equal for the largest and smallest diameters. According to this invention the wedge shaped forming tools have forming ledges of different thickness corresponding to the diameter dimension of the rolled object. The forming tools are also provided with a triangular cavity of sufficient depth and width to enable the rolling of objects of smaller diameter. A free passage of the external part of the wedge shaped tool through the triangular cavity of the adjacent wedge shaped tool is provided so that one wedge shaped tool may always enter the cavity of its adjacent wedge shaped tool. This enables the use a of one dimension of the diameter for the working cylinders of a rolling mill of a size determined by the range of diameters of objects to be rolled. Within this range objects from the smallest to the largest diameter at approximately equal lengths for both the smallest and the largest diameters of rolled objects may be rolled.

DESCRIPTION OF DRAWINGS An exemplary embodiment of the object of this invention is shown in the attached drawings where,

where FIG. 1 is a side view of the rolls, rolling an object of a larger diameter;

FIG. 2, the same view when rolling an object of medium diameter;

FIG. 3. the same view when rolling object of a small diameter;

FIG. 4 is a cross sectional view of wedge shaped forming bodies rolling a solid of rotation prior to their entrance into cavities of adjacent forming bodies, the

section being taken along a plane indicated in FIG. 6 by B-B;

FIG. 5 is the same view after parts of the wedge shaped forming bodies have entered cavities of adjacent forming bodies;

FIG. 6 is a top view of a forming body with a part of an adjacent body penetrated into its cavity, the latter forming body seen in a sectional view taken along a plane indicated in FIG. 5 by the line AA and FIG. 7 is a sectional view of the forming body taken along a plane, indicated in FIG. 6 by C-C.

DESCRIPTION OF PREFERRED EMBODIMENT FIG. 1 shows a three roll rolling mill where wedge shaped tools 1",2", 3" of equal dimensions and shape are fixed on three cylinders 4 of equal diameter D, rotating in the same direction and arranged symmetrically with respect to the axis of the rolled object 5". The rolled object 5" rotating in the opposite direction is situated in the space between the three cylinders. A product of relatively large diameter is rolled in this case, the tools on the three cylinders therefore do not come in mutual contact.

FIG. 2 shows the rolling ofa product 5' of halfthe diameter as in FIG. 1. The diameter D of the cylinders 4 is the same as in FIG. 1, the tools I, 2, 3' are however higher and mutually penetrating each other. The tool 1' penetrates into the space of tool 2, the tool 2' into the space of tool 3' and tool 3' into the space tool 1.

FIG. 3 shows the rolling ofa product 5 of the smallest diameter. The diameter of the cylinders 4 is the same as in the preceding cases, the

tools

1, 2, 3 are however still higher. The mutual penetration of the tools is also to a larger depth.

FIG. 4 shows a cross section of three wedge shaped forming

tools

1, 2, 3, the section taken along the plane, indicated in FIG. 6 by 8-8. The three tools move in the direction of the indicated arrows and are in a position where their tips 6 start to penetrate into cavities of neighboring tools.

In FIG. 5 the tools proceeded in their movements from the position shown in FIG. 4 and have entered by their tips deeper into cavities of neighboring tools.

The triangular cavities of all tools must be as large to enable a safe passage of the wedge of the neighboring tool into this cavity. The dimensions (width and depth) and the external dimensions of the entering wedges are determined by the width b of the forming ledges, which has to be conformed with the depth into which the tools are entering. The more the tools mutually penetrate (in case of rolling objects of small diameter) a smaller width b of the ledges and a larger depth c of the cavity is required and vice versa, for a smaller penetration, a larger width b of the ledges and a smaller depth c of the cavity is required. These rules are conforming with the forces acting on the forming ledges for rolling and also conform with the required dimensions of the mutually widening forming surfaces 10 and of the surfaces 11. A material of smaller diameter is formed with smaller forces and with smaller dimensions of the forming surfaces 10 and of the smoothening surfaces 11. Materials of larger dimensions are formed with larger forces acting on wider forming ledges having larger dimensions of the forming surfaces 10 and of the smoothening surfaces 11.

FIG. 6 shows a top view of the tool I viewed in the direction of the arrow S from FIG. 5 and a cross section 9 of the tool 3 along a plane indicated in FIG. 5 by A-A. As all three tools are of quite equal shape we use simultaneously the tool 1 from FIG. 6 for determination of the shape of the cross section 9 of tool 3 in the plane AA in order to have a safe clearance between the cavity of one tool and the other tool penetrating into this cavity. In FIG. 6 the points 7 8 shows the wides places of the penetrated tips of the tool 3 and points 7 8 shows positions of points 7, 8 with respect to the cavity of the tool 1. In the course of a further movement of the forming ledges in the direction of the arrows, the triangular cavity of the tool 1 will widen and the penetrating wedge of the tool 3 will simultaneously widen in the same manner. The tool 3 will freely pass through tool 1, tool 1 will pass through tool 2 and tool 2 will equally pass through tool 3.

What is claimed is:

1. An arrangement for forming of solids of rotation by cross wedge rolling comprising three working cylinders rotating in the same direction and symmetrically arranged with respect to the axis of the rolled object,

each of said working cylinders supporting an exchangeable wedge shaped forming tool, said forming tools having forming ledges converging in the direction of their rotating movement, saidforming ledges having a thickness corresponding to the dimensions of the diameters of objects to be rolled, a triangular cavity in each forming tool of sufficient depth and width between said forming ledges of each tool, to enable the rolling ofobjects of small diameter. a free passage in the external part of the wedge shaped tool through the triangular cavity of the adjacent wedge shaped tool so that always one wedge shaped tool may enter the cavity of its adjacent wedge shaped tool. whereby one dimension of the diameter of said working cylinders ofa selected size determined by the range of diameters of objects to be rolled within this range rolls objects from the smallest to the largest diameter of this range at approximately equal lengths both for the smallest and for the largest diameters of the objects to be rolled.

Claims

1. An arrangement for forming of solids of rotation by cross wedge rolling comprising three working cylinders rotating in the same direction and symmetrically arranged with respect to the axis of the rolled object, each of said working cylinders supporting an exchangeable wedge shaped forming tool, said forming tools having forming ledges converging in the direction of their rotating movement, said forming ledges having a thickness corresponding to the dimensions of the diameters of objects to be rolled, a triangular cavity in each forming tool of sufficient depth and width between said forming ledges of each tool, to enable the rolling of objects of small diameter, a free passage in the external part of the wedge shaped tool through the triangular cavity of the adjacent wedge shaped tool so that always one wedge shaped tool may enter the cavity of its adjacent wedge shaped tool, whereby one dimension of the diameter of said working cylinders of a selected size determined by the range of diameters of objects to be rolled within this range rolls objects from the smallest to the largest diameter of this range at approximately equal lengths both for the smallest and for the largest diameters of the objects to be rolled.