RU2291005C2 - Tube cold rolling mill rotation and feed mechanism - Google Patents

Abstract

FIELD: equipment of tube cold rolling mills.

SUBSTANCE: rotation and feed mechanism includes housing where are arranged: unit for converting continuous rotation to intermittent one, feed and rotation chuck, rotation chuck, each chuck has inner and outer spindles and clamp for blank with two inserts. One insert is driven from eccentric shaft with pinion. Mechanism also includes leverage systems for reciprocation motion of feed and rotation chuck; gear transmissions. Each chuck is provided with additional body mounted in outlet end of spindle for placing eccentric shaft with one insert of clamp and lever which is mounted in rocking axle and has surfaces for supporting second insert of blank clamp. Said lever is forced to additional body with the aid of elastic member creating controlled effort. Wedge for regulating position of second insert in radial direction is arranged between supporting surfaces of second insert and of lever. Gear ratio values of gear transmissions of rotation drive of each chuck are selected in such a way that for one rolling cycle (doubled stroke of stand) eccentric shaft may perform one revolution.

EFFECT: enhanced operational reliability of mechanism, improved quality of rolled tubes due to stable feed of blank at rolling process and due to possibility for controlling time period of holding blank in each chuck for one rolling cycle.

3 dwg

Description

The invention relates to the field of pipe production and relates to the improvement of the design of the mechanism for feeding and turning the cold pipe mill, which allows rolling pipes without stopping the mill for reloading according to the feed pattern and double turning the workpiece in a double stand.

The known cartridge of the cold rolling mill (see AS USSR No. 1366250, class B 21 B 21/06, decl. 01/31/86, publ. 15.01.88), containing the housing, installed in it a spindle with two clamping cams having a radial movement mechanism and gear drives of a rotation drive. The mechanism for radial movement of the lower clamping cam is made in the form of an adjusting wedge. The mechanism of radial movement of the upper clamping cam is made in the form of a gear-planetary gear, an eccentric and connecting the eccentric to the upper cam of the connecting rod.

In a known construction, the upper clamping cam is rigidly reduced through the workpiece to the lower.

Such a constructive implementation has the following disadvantages:

1. The inaccuracy of installing the lower clamping cam with a wedge will result either in the absence of gripping of the workpiece or in its pinching. In the first case, this will lead to the absence of rotation of the workpiece, and in the second, to its permanent deformation or overload of the kinematic chain of the cartridge, which causes increased loads on the drive and breakdown of its links.

2. The workpiece is clamped for a time shorter than half the rolling cycle, as a result of which axial forces arising during rolling can move the workpiece with the cartridge open, which will lead to a deterioration in the quality and accuracy of the finished pipe.

Of the known mechanisms for feeding and turning cold rolling mills, the closest in technical essence is the feeding and turning mechanism described in A.S. USSR No. 1376336, cl. At 21 At 21/00, stated 06/25/86, publ. 04/20/2000

This feeding and turning mechanism of the cold rolling mill includes a housing and a continuous to intermittent rotation converter disposed therein, a feeding and turning chuck and a turning chuck, each with a spindle driven by an eccentric shaft with a workpiece pinion gear including two liners, a lever-crank system reciprocating movement of the feed and rotation cartridge and gears.

A disadvantage of the known design of the mechanism for feeding and turning the cold rolling mill is the unstable supply of the workpiece during rolling, due to the fact that the clamping inserts leading to the workpiece in the diametrical direction from the eccentric shaft can hold it only for a small (relative to the cycle) time and the resulting axial forces from rolling the workpiece will be discarded. Lack of adjustment of the clamp stroke due to fluctuations (allowable) in the outer diameter of the workpiece will lead either to deformation of the workpiece, which prevents the workpiece from passing through the mandrel, or slipping of the clamping inserts along it, which will lead to instability or lack of feed. An unstable supply of billet during rolling reduces the quality of rolled pipes.

Another disadvantage of the known design of the feed and rotation mechanism is its lack of reliability due to the inability to adjust the clamping force of the workpiece. Excessive force during the rolling of thick-walled workpieces increases the load on the kinematic chain of the mechanism, which leads to its possible breakdown, and when rolling thin-walled workpieces ovalizes them, while the workpiece sits on the rod with its inner surface, which also causes overloading of the kinematic chain. And with little effort, the liners of the clamp will slip through the workpiece.

Another disadvantage of the known design of the mechanism is the frequent replacement of the liners of the clamp due to the lack of compensation for wear of its working surface.

The objective of the present invention is to create a mechanism for feeding and turning the cold pipe rolling mill, which allows to increase the reliability of its operation and improve the quality of the pipes by providing stable supply of the workpiece during rolling and adjusting the holding time of the workpiece by each chuck during the cycle.

The problem is achieved in that in the feed and rotation mechanism of a cold pipe rolling mill, comprising a housing and a continuous to intermittent rotation converter disposed therein, a feed and rotation cartridge and a rotation cartridge, each with an inner and an outer spindle and a workpiece clamp, including two liners, one of which is driven by an eccentric shaft with gear, a lever system for reciprocating movement of the feed and rotation cartridge and gears, according to the invention, each cartridge is equipped with an additional housing at the output end of the internal spindle for an eccentric shaft with one of the clamping shells and a swing axis mounted in this housing with a lever located on it with supporting and seating surfaces under the second blanking clamp of the workpiece, pressed against the additional housing by an elastic element adjustable in force, and a wedge placed between the abutment surfaces of the second clamping sleeve of the workpiece and the lever and adjusting the position of the second clamping sleeve in the radial direction.

Such a constructive implementation of the feed mechanism and the rotation of the cold rolling mill will increase its reliability and improve the quality of the pipes.

This is achieved due to the possibility of regulating the gripping force of the workpiece by pre-compressing an elastic element, such as a spring, pressing the lever with the second insert clamp the workpiece to the body. With an adjustable effort to capture the workpiece, the workpiece feed stability during rolling is ensured, its residual deformation is absent, and the load on the kinematic chain of the mechanism is excluded when the workpiece is gripped, causing damage to its elements. In the proposed design of the mechanism, by adjusting the position of the inserts by the wedge, it is possible to set the necessary holding time for the workpiece by clamping each cartridge during the rolling cycle. The holding time of the workpiece with each cartridge can be set longer than half the cycle, that is, the workpiece will be constantly clamped with one or two chucks. This will keep it from moving when axial forces occur during rolling, ensure feed stability and improve the quality of the pipes obtained. Also, by moving the wedge, it is possible to compensate for the wear of the liners of the clamps that occurs during operation of the mechanism.

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

figure 1 shows a kinematic diagram of the mechanism for feeding and turning the cold rolling mill;

figure 2 is a section aa in figure 1;

figure 3 is a section bB in figure 2.

The feed and rotation mechanism of the cold pipe rolling mill consists of a housing 1, a planetary-crank transducer 2 of continuous rotation into intermittent, a rotation cartridge 3, a supply and rotation cartridge 4, a lever system 5 of the reciprocating movement of the supply and rotation cartridge 4, gear gears 6-7, 8-9-10-11 continuous rotation and gears 12-13, 14-15, 16-17-18, 19-20 intermittent rotation, the drive shaft 21 with an electric motor 22. The rotation cartridge 3 consists of an internal 27 and outer 28 spindles. At the output end of the inner spindle 27, which has intermittent rotation from the gear 17, an additional housing 29 is fixed with an eccentric shaft 30 that moves the clamping insert 32 through the connecting rod 31. A gear 33 is fixed to the eccentric shaft 30, which is meshed with the gear 11 of the outer spindle 28. In the additional housing 29 on the swing axis 34 there is a lever 35 with supporting 36, 37 and 38 seating surfaces under the second clip liner 39, pressed against its supporting surface 36 with a force-adjustable elastic element 40, for example, a spring, through a rod 41 capable of rotation in a plane perpendicular to the axis of swing of the lever. A wedge 42 is placed between the supporting surfaces 37 of the clip liner 39 and the lever 35, moving the liner 39 Agim radially.

The feed and rotation cartridge 4 is similar in design to the rotation cartridge 3, but its inner spindle 27 is additionally equipped with a thrust unit 43 interacting via a lever system with a crank shaft 44.

The gear ratios of gears 6-7, 8-9-10-11, 12-13, 16-17-18 in the rotation drive of each cartridge are selected in such a way that for one rolling cycle (double stand travel) the eccentric shaft 30 makes one revolution .

The mechanism works as follows.

The rotation from the electric motor 22 through the gears 6-7, 8-9-10 is transmitted to the gear 11 of the outer spindle 28 of each chuck 3, 4. The intermittent pulse occurring at the output of the converter 2 is transmitted through the gears 12-13, 16-17 -18 to the internal spindle 27 of each of the chucks 3, 4, and through the gears 14-15, 19-20 and the lever system 5 to the stop assembly 43 of the inner spindle 27 of the feed and rotation cartridge 4. Gear ratios of the gears 12, 13, 16, 17 are selected in such a way that for a cycle equal to the double stroke of the working stand, the internal The first spindle 27 of each cartridge is rotated at an angle of 48 ° -53 °, and the gears 12, 13, 14, 15, 19, 20 provide rotation of the shaft 44 through an angle of 180 ° at time points corresponding to the extreme forward and extreme rear position of the stand. The gear ratios of the gears 6, 7, 8, 9 are selected in such a way that when applying continuous rotation of the gear 11 to the gear 33 and the pulse rotation of the internal spindle 27, the rotation angle of the eccentric shaft 30 is 360 °.

Cartridges 3 and 4 work in antiphase, that is, in the rear extreme position of the stand, the feed and rotation cartridge 4 is closed and the rotation cartridge 3 is open, and in the front extreme position of the stand - vice versa.

Submission is as follows.

Through gears 12-13, 14-15, 19-20, the pulse from the output of the converter becomes 180 ° and is transmitted to the crank shaft 44 and through the lever system 5 acts on the thrust unit 43 of the inner spindle 27 of the feed and rotation cartridge 4 and moves it linearly . In the rear extreme position of the stand, the rotation cartridge 3 is open, that is, the eccentricity of the shaft 30 is removed from the axis of the workpiece and the liners 32, 39 of the clamp do not hold the workpiece, and the feed and rotation cartridge 4 is closed, that is, the eccentricity of the shaft 30 is close to the axis of the workpiece and liners 32, 39 clamps of this cartridge hold the workpiece and, moving with the workpiece, carry out its supply and rotation. In the front extreme position, the rotation cartridge 3 is closed, rotates the workpiece and holds it from axial displacement, and the feed and rotation cartridge is open and returns to its original position. Thus, the mechanism implements a rolling circuit with a double rotation and one feed per cycle of the working stand. Holding the workpiece 45 is carried out when the clamp insert 32 is moved by the eccentric shaft 30, while the compression force of the workpiece is regulated by an elastic element 40, above which the lever 35 rotates on the swing axis 34, thereby preserving the workpiece gripping force and not overloading the kinematic chain of the mechanism. The wedge 42, moving the liner 39 of the clamp in the radial direction, it is possible to adjust the duration of holding the workpiece during the rolling cycle, as well as to compensate for the wear of the clamps.

The proposed mechanism for feeding and turning the cold pipe rolling mill in comparison with the known ones will increase its reliability and improve the quality of the pipes obtained.

Claims (1)

A feed and rotation mechanism for a cold pipe rolling mill, comprising a housing and a continuous to intermittent rotation converter disposed therein, a feed and rotation cartridge and a rotation cartridge, each with an inner and an outer spindle and a workpiece clamp, including two liners, one of which is driven by an eccentric shaft with gear, lever system for reciprocating movement of the feed and rotation cartridge and gears, characterized in that each cartridge is provided with an internal spindle located at the output end an additional housing for an eccentric shaft with one of the liner inserts and a swing axis mounted in this housing with a lever located on it with supporting and seating surfaces under the second blank of the workpiece clamp, pressed against the additional housing by an elastic element adjustable in force, and a wedge placed between the supporting surfaces the second liner clamp the workpiece and the lever and adjusting the position of the second liner clamp in the radial direction.

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