SU1706739A1 - Pipe-welding mill roll - Google Patents

Abstract

The invention relates to the production of electric welded straight pipes, in particular to pipe welding mills with non-driven forming tools. The purpose of the invention is to increase the resource of the roll when it is used as a tool in mills with non-driven forming tools and preserve its exciting ability. The roll of the pipe-welding mill contains sections mounted on the shaft in the form of discs and an insert made of elastic material located between them. An insert made of an elastic material is impregnated in the form of a ring located at the bottom, a ring with a width of 0.25-0.55 and a height of 0.50-0.70 of the diameter. 1 ill., 1 tab. with Ј

Description

The invention relates to the production of electric welded straight pipes, in particular to pipe welding mills with non-driven forming tools.

Widely known are thinner rolls of a pipe welded mill made of structural steel.

However, the conditions of friction between the welded workpiece and the contact surface of the carrying roll do not ensure the creation of a sufficient condition for the joint, which leads to the workpiece slipping in the rolls and the stability of the welding process.

Known roll gauge mill for the production of welded direct-flow pipes containing the lower and upper composite rolls, each of which is made in the form of

on the shaft of the side metal sections and working sections of elastic material, mounted on a splined hub.

The implementation of the working sections of elastic elastic material leads to an increase in the contact forces of friction and, as a consequence, the magnitude of the pulling force of the rolls. However, at the point of contact of the roll with the welded workpiece, heat is generated, which is accumulated by the elastic material of the working sections, which has a high heat capacity and low thermal conductivity. Heating of the working sections leads to their plastic deformation and destruction.

A roll of a pipe electric mill is known; it contains disc sections mounted on a shaft.

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with

and an insert made of an elastic material located between them, while the insert is made with a surface profile under the working section similar to the profile of the working surface with an angle of coverage of the welded workpiece equal to 120-160 °.

Constructive execution of the roll, when the insert, is made of elastic material, has a large contact surface with disks of a material with high thermal conductivity, provides the necessary temperature difference between the heated insert and the disks. However, the uneven wear of the working surface of the insert requires its frequent replacement, although some parts can still be used.

The purpose of the invention is to increase the resource of the roll when it is used as a tool in mills with a non-invisible forming tool and to keep its gripping ability constant.

The goal is to accomplish the implementation of a pipe-welding mill comprising sections mounted on a shaft in the form of discs and an insert made of elastic material located between them, in which the insert of elastic material is made in the form of a downstream strand of a ring with a width of 0.25-0.55 height C, 50 0.70 from the diameter of the stream.

The drawing shows a roll of a pipe-welding mill, a general view.

The roll of the pipe welding mill contains sections 1 and 2 mounted on the shaft and an insert made of elastic material made in the form of a ring 3, whose width is 0.25-0.55, and h 0.50-0 in height; 70 from the diameter of the stream.

Polyurethane was taken as the elastic material for the insert.

With a BCTaeKk width of more than 0.55 of the diameter, the stream in the roll of the pipe welding mill is used as

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five

five

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or

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40

45

50

Blowing in the mills with a non-driven forming tool, nonetpei is lost. Hofl stability of a welded pipe billet (its squeeze), and if the insert width is less than 0.25 en-stream diameter, the contact area between the welded pipe billet and the roller does not provide sufficient gripping ability, which leads to the workpiece slipping .

When the insert height is more than 0.70 from the diameter of the stream, due to the low thermal conductivity of the elastic material (polyurethane), the insert is heated up, which leads to its deformation and destruction, and when the insert height is less than 0.50 from the diameter of the stream, the production of the ring becomes time-consuming and besides, its strength is insufficient, which also reduces the service life of the insert.

Comparative data on testing rolls made of structural steel and rolls made in accordance with the claimed technical solution are presented in the table.

Rolls with a polyurethane insert were tested in the production of thin-walled pipes in an argon-arc welding machine (ADST 5-55).

Claims (1)

Claims. A roll of a pipe-welding mill containing sections in the form of discs mounted on the shaft and an insert made of elastic material between them, characterized in that, in order to increase the life of the roll when it is used as a tool in mills with non-driven forming tools and preserve its gripping ability The insert of elastic material is made in the form of a ring, which is installed in the bottom of the stream with a width of 0.25-0.55 and a height of 0.5-0.7 of the diameter of the stream. Note. Roll 1 metal, roll 2 polyurethane, rolls with polyurethane insert. lo