RU2384376C1 - Rolling mill of cold-rolling mill for pipes rolling - Google Patents

Abstract

FIELD: metallurgy.

SUBSTANCE: rolling mill of cold-rolling mill for pipe rolling contains movable force stand with bearing rails and rack bars and movable cartridge with working rollers, bearing assemblies, pinion gears and removable gages. Removable gages are implemented as segmented and are fixed on working rollers by bandages. Each bearing roller by width is implemented with additional bearing sections, enveloping bandages of gage. Each bearing rails allows longitudinal grooves doe passing of mentioned bandages, butt grooves for passing of gage and inclined groove at front butt for installation of movable cartridge into load-bearing stand.

EFFECT: invention provides increasing of quality of rolled pipes ensured by increasing of rigidity, to reduce steel intensity, labour-output ratio of its fabrication and power consumption during stand operation.

8 dwg

Description

The invention relates to the field of pipe production, and more specifically to the design of the working stand of the cold rolling mill of pipes with a movable roller cassette and power bed.

The transfer of rolling forces from calibers to the power bed is through the contact of the cylindrical bearing surface of the work roll with the plane of the supporting rail. Cold rolling of pipes of large diameter (D _tr > 200 mm) is carried out with significant rolling forces, which leads to the need to use work rolls with a large diameter of the supporting surface and weight.

The diameter of the supporting surface of the work roll determines the dimensions of the power bed and the length of its stroke. With an increase in the diameter of the supporting surface of the work roll, the dimensions and stroke length of the power bed increase, and this leads to a decrease in the rigidity of the work stand and to an increase in the load on the drive mechanism and the main drive. A decrease in the rigidity of the working stand affects the quality of the rolled tubes, and an increase in the load on the drive mechanism and the main drive increases the dimensions of these mechanisms and their energy consumption.

One of the ways to solve the problem is to create a new design of the working stand, in which the work roll has a small diameter of the supporting surface by increasing its length.

Known working stand of the cold rolling mill, see RF patent No. 2286219, IPC B21B 13/18, B21B 21/00, decl. 04/05/2005, publ. 10/27/2006

Known stand contains a movable power bed with support rails and a movable cassette with three deforming rollers. The deforming rollers have cantilever support pins from the ends contacting with the support rails.

A disadvantage of the known design of the working stand is the lack of strength and rigidity due to the high bending stresses in the cantilevered trunnions of the deforming rollers, which limits the productivity of the mill and reduces the quality of rolled pipes.

Also known is the working stand of the cold rolling mill described in RF patent No. 2061565, IPC B21B 21/00, decl. 03/19/1992, publ. 06/10/1996, which contains a movable power bed with support rails and gear racks and a movable cassette with work rolls and gears. In this stand, the width of the support rail is equal to the thickness of the caliber, and the supporting surface of the roll is a barrel of caliber.

The disadvantages of this design of the working stand are its insufficient rigidity, increased dimensions and mass of the stand, due to the small stroke of the rolls along the deformable pipe in comparison with the course of the power bed.

Of the known working stands of cold rolling mills, the closest in technical essence is the working stand described in RF patent No. 2297890, IPC B21B 13/18, B21B 21/00, decl. September 15, 2005, publ. 04/27/2007

This working stand of the cold rolling mill comprises a movable power bed with support rails and gear racks, a movable cassette with work rolls having a cylindrical support surface with bearing supports, gears interacting with gear racks, and interchangeable gauges.

The supporting surface of the work rolls is made maximum in diameter and equal to the outer diameter of the caliber, which increases the dimensions and weight of the working stand, as well as the stroke length of the power bed.

A disadvantage of the known design of the working stand of the cold pipe rolling mill is that it has insufficient rigidity due to the large size and weight, which negatively affects the quality of the rolled products. In addition, the increase in the stroke length of the power bed, the large dimensions and the mass of the mill increase the energy consumption of the mill when rolling pipes, increase the metal consumption and the complexity of manufacturing the mill.

The objective of the present invention is to create a working stand for a cold pipe rolling mill, which allows to improve the quality of rolled pipes by increasing stiffness, as well as reduce the metal consumption and the complexity of manufacturing a working stand and reduce energy consumption when rolling pipes.

The task is achieved by the fact that in the working stand of the cold pipe rolling mill comprising a movable power bed with support rails and gear racks and a movable cassette with work rolls, bearing bearings, gears and interchangeable gauges, according to the invention, interchangeable gauges are made segment and mounted on work rolls bandages, and each supporting rail in width is made with additional supporting sections covering caliber bandages, with longitudinal grooves for passing these bandages, with end grooves and for skipping the caliber and with an inclined groove at the front end for installing the movable cartridge in the power frame.

Such a constructive implementation of the working stand of the cold pipe rolling mill will improve the quality of rolled pipes by increasing its rigidity.

This is achieved by reducing the diameter of the work rolls and increasing the length of the supporting surface, which allowed to reduce the stroke length of the power frame. By reducing the diameter of the work rolls, the dimensions of the stand, its metal consumption and the complexity of manufacturing are reduced.

Performing segment gauges and fastening them to the rolls with the help of bandages, as well as making the support rail with additional supporting sections covering the bandages, allowed to increase the length of the cylindrical supporting surface of the work roll.

The implementation of the support rail with grooves for skipping bandages, caliber and for installing the cassette in the frame also allowed to reduce the dimensions and weight of the cage and to reduce the stroke length of the power frame.

Reducing the weight and dimensions of the stand reduces the metal consumption and the complexity of manufacturing the stand and increases its rigidity, which increases the quality of the rolled pipes. Reducing the stroke length of the power bed reduces energy consumption when rolling pipes.

To explain the invention, a specific embodiment of the invention is provided below with reference to the accompanying drawings, in which:

figure 1 - shows the working stand of the cold rolling mill;

figure 2 is a section aa in figure 1;

figure 3 is a section bB in figure 1;

figure 4 is a section bb in figure 3;

figure 5 is a section GG in figure 3;

figure 6 - section DD in figure 2;

Fig.7 is a view along arrow E in Fig.6;

Fig.8 is a view along arrow Zh in Fig.6.

The working stand of the cold pipe rolling mill comprises a movable power bed 1 with support rails 2 having a flat supporting surface and gear racks 3, a movable cassette 4 with working rolls 5 located in it. The working roll 5 comprises a shaft 6 with a cylindrical supporting surface “a” installed in the cassette 4 on two bearing bearings 7, a segment gauge 8, mounted on a rectangular protrusion 9 of the shaft 6 with shafts 10, and a gear 11 that engages with a gear rack 3. Each support rail 2 is made in width with an additional and supporting sections 12, covering bandages 10 of caliber 8, has longitudinal grooves 13 for skipping bandages 10, end grooves 14 for skipping caliber 8 and an inclined groove 15 made at the front end for mounting movable cassette 4 in a movable power frame 1. The supporting rail has a flat supporting surface "b". The length of the cylindrical supporting surface "a" of the work roll 5 is made equal to the width of the supporting rail 2. The supporting surface "a" of the work roll 5 is made the maximum length, overlapping the width of the caliber 8, this allowed for a given rolling force to make the diameter of the supporting surface "a" minimally acceptable.

Thus, the contact of the cylindrical supporting surface "a" of the work roll 5 with the flat supporting surface "b" of the rail 2 occurs in three sections - one section opposite the stream of caliber 8 and two additional sections located on both sides of the roll 5 beyond the dimensions of the bandages 10.

In the process, the power bed 1 performs a reciprocating movement using a crank drive (not shown). The cassette 4 with the work rolls 5 moves reciprocating along the power bed 1. The work rolls 5, mounted in the cassette on the bearing bearings 7, perform the reciprocating and swinging movement by means of gears 11 engaged with the gear racks 3 during the rolling process. The work rolls 5, rolling along the rails 2, deform the pipe with calibers 8. In this case, the bandages 10 are moved in the longitudinal grooves 13 of the support rails, and the segment gauges 8, making a rocking movement, alternately enter the extreme positions in the end grooves 14 of the support rails 2. When transshipment for installing the movable cassette 4 in the power frame 1, gears 11 engage with gear racks 3, while gauges 8 must be turned to a certain angle, which will ensure a normal turn of the gauge stream during rolling. For this, gauges 8 are inserted into inclined grooves 15 made in the front ends of the support rails 2.

The proposed working stand of the cold pipe rolling mill in comparison with the known ones allows to improve the quality of rolled pipes by increasing stiffness, reduce the metal consumption, the complexity of its manufacture and energy consumption during operation of the mill.

Claims (1)

The working stand of the cold pipe rolling mill, comprising a movable power bed with support rails and gear racks and a movable cassette with work rolls, bearing bearings, gears and interchangeable gauges, characterized in that the interchangeable gauges are segmented and mounted on the work rolls with bandages, and each supporting the rail in width is made with additional supporting sections covering caliber bandages, with longitudinal grooves for passing these bandages, with end grooves for skipping caliber and with an inclined groove and the front end for positioning the movable cassette into the power base frame.

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