RU2333054C1 - Composite forming roll - Google Patents

Abstract

FIELD: technological processes.

SUBSTANCE: forming roll contains axis with pile and threaded section, binding installed at axis and coupling nut that is screwed onto threaded section of axis. The objective is achieved by the fact that in coupling nut on the side that faces hard-alloy binding, threaded openings are made that are evenly distributed along circumference and parallel to its axis, into which stop bolts are screwed in, and coupling nut is equipped with fixation elements in the form of screws that are screwed in through threaded radial openings. Binding is made as split and consists of two hard-alloy tubular elements installed on axis, on the surface of which streams are arranged, and is equipped with gaskets, which are installed on the axis on both sides of binding, at that annular cuts are made at the end portions of tubular elements.

EFFECT: increase of roll resource and simplification of its assembly and disassembly.

2 dwg

Description

The invention relates to rolling production, and more particularly to the design of the work roll used for hot rolling of steel sections.

Known composite rolling roll containing a housing, a bandage of carbide material, a flange and coupling elements. The end surfaces of the bandage and the surfaces of the body and flange facing them have a taper, and the vertices of the forming cones are located on the axis of rotation of the roll. In addition, the roll is equipped with rolling bodies located uniformly on both end surfaces of the bandage, and grooves of equal radius are made on the end surfaces of the housing and flange on the side of the bandage, in which the specified rolling bodies are installed [1].

A disadvantage of the known roll is its low resource, because during hot rolling, thermal deformation of its elements and rolling elements occurs. In addition, the disassembly and assembly of the roll of such a design is complex and time-consuming.

Also known is a rolling roll containing an axle with a shoulder, a carbide brace and a tightening nut screwed onto a threaded portion of the axis, and also an intermediate ring, seated on an axis with an interference fit. The axis is connected to the intermediate ring with the help of round pins installed on the press fit evenly around the circumference of the roll barrel along the joint between the intermediate ring and the shoulder. Also in the intermediate ring there is a groove in which a protrusion of a rectangular shape is placed on the brace [2].

The disadvantage of a roll of this design is the low operating life, since due to the difference in the thermal expansion coefficients of the carbide band and the axis, tensile stresses arise in the band, which cause increased wear, cracks and chips. Dismantling-assembling such a roll is difficult and time-consuming.

The closest in design to the present invention is a composite rolling roll containing an axis with a shoulder and a threaded section, a bandage mounted on the axis, and a coupling nut screwed onto the threaded section of the axis, with fixing elements in the form of screws screwed into through threaded radial holes nuts [3].

The disadvantages of such a composite rolling roll are its short service life due to low wear resistance, especially when rolling long sections, as well as the complexity of assembly and disassembly.

The technical problem solved by the invention is to increase the resource of the roll, simplifying its assembly and disassembly.

To solve the technical problem in the known design of a composite rolling roll containing an axis with a shoulder and a threaded section, a bandage mounted on the axis, and a coupling nut screwed onto the threaded section of the axis, with fixing elements in the form of screws screwed into threaded radial holes of the nut , according to the proposal, in the coupling nut on the side facing the brace, threaded holes are made evenly distributed around the circumference, parallel to its axis, into which the stop bolts are screwed, while the brace is made detachable, consisting of two carbide tubular elements planted on an axis with streams on their surfaces and ring cuts at the end sections, and gaskets are installed on the axis on both sides of the bandage.

The composite rolling roll contains an axis 1 (Fig. 1) with a shoulder 2 and a threaded section. A gasket 3 is put on the axis 1 and a detachable bandage is set with an interference fit, consisting of two carbide tubular elements 4 and 5 with round streams on the surface. Behind the tubular element 5, a second gasket 3 is placed on the axis. Thus, the gaskets 3 are mounted on the axis 1 on both sides of the bandage.

A tightening nut 6 is screwed onto the threaded portion of the axis 1, on the side of which, facing the bandage, six threaded holes 7 are uniformly distributed around the circumference (FIG. 2), into which the stop bolts 8 are screwed.

At the end sections of the tubular elements 4 and 5, annular cuts 9 and 10 are made. In addition, three through radial threaded holes are made in the coupling nut 6, into which the locking screws 11 are screwed.

The device operates as follows. Before starting the operation of the assembled roll, the coupling nut 6 is fixed relative to the axis 1 by screwing the three locking screws 11 until their pointed ends are pressed tightly onto the threaded section of the axis 1. Then, the locking bolts 8 are turned out, which, through their gasket 3, create preliminary axial compression stress in the tubular elements 4 and 5, clamping them together and pressing through the gasket 3 to the shoulder 2. In the same way prepare the second roll of the pair.

Pre-stressed rolls are installed in the bearings located in the pillows, dumped into the cage and connected to the drive of their rotation. Hot rolling varietal strip is carried out in one of the calibers formed by round streams on the surface of the tubular elements 4 and 5 of the upper and lower rolls.

In the process of hot rolling of the strip, the carbide tubular elements 4 and 5 are heated, especially intense in the surface layer in contact with the hot strip. Due to the presence of annular cuts 9 and 10, free thermal expansion of the most heated surface layers of tubular elements 4 and 5 is achieved, which eliminates the likelihood of cracking, favorably affects the resistance of the roll. Gaskets 3 mounted on both sides of the carbide brace provide uniform transmission of axial load on the surface of the ends of the carbide tubular elements 4 and 5 and prevent the formation of cracks and chips in them.

The thermal elongation of the roll axis 1 is compensated by the oppositely directed thermal elongation of the stop bolts 8, due to which, when the roll is heated, the favorable axial compression stress of the tubular elements 4 and 5 between the collar 2 and the coupling nut 6 does not decrease.

When the wear of the caliber in which the rolling was carried out, the transition to the second, then to the third and fourth calibers is carried out.

A composite roll with worn gauges is disassembled. To do this, the thrust screws 8 are screwed into the coupling nut 6, removing the axial stress of the pre-compression of the bandage. Then, the locking screws 11 are turned out and the loose coupling nut 6 is screwed from the threaded portion of the axis 1. After that, the gasket 3, the carbide tubular elements 5 and 4 with worn streams and the gasket 3 adjacent to the shoulder 2 are sequentially removed from the axis 1.

Carbide tubular elements 5 and 4 with worn streams are replaced with new ones and the composite rolling roll is assembled in the reverse order.

The technical and economic advantages of the proposed composite rolling roll are that the use of a bandage consisting of two carbide tubular elements in which a preliminary compression stress is created, the presence of annular cuts at the end sections of the tubular elements and gaskets mounted on the axis on both sides of the bandage, provide increase in roll resource, exclude the formation of cracks and chips in it. The presence of a coupling nut with thrust bolts screwed into it allows you to compensate for the thermal elongation of the axis and maintain the level of prestress during heating and cooling of the roll. Dismantling and assembling the roll of the proposed design is simplified, does not require large labor costs and the use of special equipment.

The prototype device was adopted as the base object. Application of the proposed design will reduce the expenditure coefficient of the rolls by 20-25%.

Literature

1. Auth. testimonial. USSR No. 1233207, IPC В21В 27/02, 1986

2. Japanese application No. 60-54211, IPC B21B 27/02, 1985

3. Auth. testimonial. USSR No. 2236920, IPC В21В 27/02, 2004

Claims (1)

A composite rolling roll containing an axis with a shoulder and a threaded section, a bandage seated on the axis, and a coupling nut screwed onto the threaded section of the axis, with fixing elements in the form of screws screwed into the threaded radial holes of the nut, characterized in that in the coupling nut on the side facing the bandage, threaded holes uniformly distributed around the circumference are made parallel to its axis, into which the thrust bolts are screwed, while the bandage is made detachable, consisting of two carbide tubular mounted on the axis elements with streams on their surfaces and annular cuts at the end sections, and gaskets are installed on the axis on both sides of the bandage.

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