RU2236919C1 - Mill for continuous cold drawing-rolling of tubes - Google Patents

Abstract

FIELD: rolled tube production processes and equipment, namely production of tubes of non-ferrous metals.

SUBSTANCE: mill for cold drawing - rolling tubes on self-aligning mandrel, mainly copper tubes from continuously cast coiled blank includes uncoiling apparatus, working organ with drawing die arranged in it, traction unit and receiving apparatus. Working organ is in the form of rolling rollers driven to rotation by means of drive unit and having constant profile of roller groove for forming around rolling axis grooved pass for outer shape of ready tube. Bearing assemblies of rotation axles of rollers are placed in fixed casing supporting drawing die. The last has radial grooves. Rolling rollers are arranged in said grooves at minimum gap at their ends. Mill also includes straightening and guiding apparatuses that are mounted along drawing - rolling axis between uncoiling apparatus and working organ. Straightening and guiding apparatuses are provided with rollers driven to rotation by means of drive unit and having movable rotation axles that may be forced to tube-blank by action of controlled effort. In deformation zone created by drawing die, self-aligning mandrel and rolling rollers tube is simultaneously drawn and rolled. It allows to make optimum tube-blank during one technological transition for further production of merchant tubes of predetermined volume and assortment.

EFFECT: enhanced efficiency, lowered invested and maintenance costs.

5 dwg

Description

The invention relates to pipe rolling production and can be used in the manufacture of pipes, for example, copper, from a continuously cast billet rolled into a bay.

A known mill for periodic cold rolling of pipes on a self-aligning mandrel, on which rolling from a continuously cast billet rolled into a bay is possible. For this, the mill contains a non-drive unwinding device, the correct device, a mechanism for periodically feeding the workpiece to the working body, including rolling rolls (rollers) with a variable profile of the working stream, fixed by their rotation axes in the housing, moved along the rolling axis by a certain amount of "forward and backward" from the drive, and the shafts of the rolling rolls in this case receive a “back and forth” rotation from the gears fixed to them and meshed with rails mounted on the guides of the movement of the housing. The guides of the housing and the housing itself are periodically rotated from the drive by a predetermined angle. In the working body, the periodically supplied portion of the billet pipe is deformed by rolling rolls on a self-aligning mandrel located inside the pipe.

The mill also contains a bending device into which the finished pipe enters upon exiting the working body, and a receiving device where the bent pipe is placed in a basket fixed to the device or formed into a bay (Such a machine was developed and manufactured by OJSC AZTM, damn. A2228-00-00 )

The main disadvantage of this mill is the low average speed of the pipe through the working body and, therefore, the low aggregate productivity of the mill.

Closest to the proposed is a mill for continuous cold drawing of pipes on a self-aligning mandrel from a workpiece rolled into a bay, into a finished pipe also rolled into a bay. These are the so-called drum drawing mills with continuous intake of the finished pipe (Mill TBN-1800, drawing. A2190-00-00, produced by OJSC AZTM).

This mill, like similar mills manufactured by other companies (for example, Marshall Richards; Montbar; Aetna Standards, Koch, etc.), implements high speeds of the pipe through the working body and achieves high productivity during processing such pipes, when it is necessary to perform the main compression in diameter and small on the wall.

The mill for this purpose comprises an unwinding device, including a drive, adjustable in speed of rotation of the basket from the bay of the billet pipe; a transport device for periodically moving baskets with pipe bays located in them along the mill and fixing them in technological positions; a working body, including a device for holding the die and perceiving the drawing force (fiber holder), a pulling unit in the form of a drawing drum rotated by a speed-adjustable drive and creating the necessary drawing force in the finished pipe; a receiving device, including a drive, adjustable in speed of rotation of the basket, where the finished pipe is laid, continuously coming down from the drawing drum.

Thus, in this mill, the process of cold deformation of the pipe is carried out in the working body by pulling the billet pipe through the die held in the working body and the mandrel located inside the pipe in the die region and self-installing under the forces acting in the deformation zone.

The main disadvantages of the cold pipe drawing mill from bay to bay on a self-aligning mandrel include the inability to thin the pipe wall in one pass of a certain size, because this is limited by the drag force, which should not exceed the tensile strength of the finished pipe.

This drawback can be reduced to some extent due to the organization of drawing with back-up or anti-tension, but the design of the mill and its working body (fiber holder) do not allow to organize such drawing.

Thus, the process of pipe deformation is forced to lead in several transitions, i.e. in portions, until the required diameter and wall of the commodity pipes are reached. In cases where a cast pipe is used as an initial billet, in which the real ratio of diameter to wall thickness is not more than 6 ... 8, production of commodity pipes with a given wall thickness and a ratio of diameter to wall thickness in the range of 12 ... 20 (the most common sizes ) becomes very difficult, and sometimes impossible.

These circumstances in the conditions of real production of pipes of specified volumes of output and nomenclature will require the availability of additional units of technological equipment, i.e. investment and, accordingly, operating costs.

The aim of the present invention is to provide cold deformation in one transition with increased compression both in diameter and in the wall and increased speeds of movement through the working body of pipes, such as copper, from a continuously cast billet rolled into a bay. This will reduce investment and operating costs in organizing the production of pipes of specified volumes and nomenclature.

The specified technical result is achieved by the fact that the proposed continuous cold drawing-rolling pipe mill (NHVPT mill) contains an unwinding device, a working body with a wire placed in it, a pulling unit and a receiving device for laying the finished pipes in the bay, and the working body is made in the form of rotatable from the drive of rolling rollers having a constant stream profile and forming a gauge of the outer profile of the finished pipe around the rolling axis. The supports of the rotation axes of the rolling rollers are placed in a motionlessly mounted casing, on which a die is fixed in which radial grooves are made, and rolling rollers are placed in these grooves with a minimum clearance at the ends. In addition, the mill is equipped with a correct and setting device installed along the drawing-rolling axis between the unwinding device and the working body, while the correct and setting devices are equipped with rollers rotatable from the drive with movable rotation axes so that the rollers can be pressed by streams to the workpiece pipe with adjustable force.

The invention and an example of its implementation are illustrated by drawings. Figure 1 schematically shows a General view of the camp NHVPT, figure 2 is a longitudinal section aa of the working body; figure 3, 4, 5 - transverse sections BB, BB, GG of the working body. All drawings show the relative positions of the parts during the cold deformation of a circular pipe.

NHVPT mill contains (see Fig. 1) an unwinding device 1, on which a bay 2 of a workpiece pipe 3 is placed; auxiliary correct exhaust device 4; correct device 5; auxiliary device for preparing the end of the pipe billet 6; driver 7; working body 8; a bending and exhaust device (pulling unit) 9, which pulls the finished pipe 10 out of the working body, bends it and feeds it to the basket 11, where it turns into coils 12 in turns, while the basket rotates while being fixed in the receiving device 13 having a drive rotation (not shown in FIG. 1).

In figure 2, 3, 4 and 5, the rolling rollers 14 are mounted on the shafts 15 and 16, the supports of which 17 are placed in the housing 18. On the shafts 15 and 16 are fixed bevel gears 19, which are interconnected. The housing 18 is fixed with screws 20 of the die 21, it has radial grooves 22, into which the ends of the disks include rolling rollers 14.

Inside the pipe in the region of the die 21 and the rolling rollers 14 is a self-aligning mandrel 23, which is held during operation in the deformation zone by the forces acting in it. Figure 5 (section BB) shows the pipe 24 in the state of deformation from the workpiece 3 (see figure 4 section GG) into the finished pipe 10 (see figure 3).

и

обозначают, что данные ролики вращаются от привода в направлении стрелок, а значки ↑ и ↓ показывают, что оси вращения роликов перемещаются от приводов в направлении стрелок и при остановке будут находиться под действием сил заданной (регулируемой) величины. Приводы вращения и перемещения роликов на чертежах не показаны.In the drawings, the icons

and

indicate that these rollers rotate from the drive in the direction of the arrows, and the ↑ and ↓ icons indicate that the axis of rotation of the rollers move from the drives in the direction of the arrows and when stopped will be under the influence of forces of a given (adjustable) value. Drives for rotating and moving rollers are not shown in the drawings.

Stan NHVPT works as follows. On the unwinding device 1 is laid a bay of the workpiece pipe 3, obtained, for example, by continuous casting.

) отведены от приводных (со значком

), которые начали вращаться одновременно с роликами устройства 4. Когда конец трубы 3 пройдет первую пару оппозитных роликов правильного устройства 5, неприводные ролики делают ход на настроенную величину. Начинается правка заготовки 3 и продвижение ее к установке 6. Одновременно с ходом неприводных роликов разводятся ролики устройства 4 и труба вытягивается из бухты 2 правильным устройством 5. Выправленный конец трубы 3 входит во вспомогательное устройство подготовки конца трубы 6, останавливается, удерживаемый роликами правильного устройства, которым дана команда на остановку вращения.The upper end of the pipe 3 from the bay 2 is placed between the open (divorced) rollers of the right exhaust device 4. From the command, the rollers are reduced and clamp the pipe-workpiece, at the same time a command is given to rotate the rollers. The end of the pipe 3 under the action of friction forces in the place of contact with the rollers advances to the correct device 5, which has non-driven rollers (without an icon

) away from the drive (with the icon

), which began to rotate simultaneously with the rollers of device 4. When the end of the pipe 3 passes the first pair of opposed rollers of the correct device 5, the non-drive rollers make a move by the set value. Editing of workpiece 3 begins and its advancement to installation 6. Simultaneously with the non-drive rollers, the rollers of device 4 are opened and the pipe is pulled out of the bay 2 by the correct device 5. The straightened end of the pipe 3 enters the auxiliary device for preparing the end of the pipe 6, stops, held by the rollers of the correct device, who gave the command to stop rotation.

The end of the pipe is prepared for deformation in the working body 8. For this, a portion of technological lubricant is injected into the pipe. A first transverse dent is applied to the pipe at a distance from the end exceeding the length of the mandrel 23, a mandrel 23 is inserted all the way, and a second transverse dent is applied at a distance from the first equal to the length of the mandrel. Both dents limit the possible movement of the mandrel inside the pipe during its movement. After applying the second dent, the end of the pipe 3 is prepared, the rollers of the correct device 5 are turned on again, and the previously diluted rollers of the driver 7 are turned on. 7 last from the team are reduced and clamp the pipe 3 with the force set to a predetermined value. The end face of the pipe 3 enters the working body 8, abuts against the cone of the die 21 and under the action of the total axial force created by the correct and master devices, the pipe 3 is pressed through the die 21, decreasing the outer diameter. The rolling rollers 14 begin to rotate from the same command as the rollers of the driver 7, and at some point touch the outer surface of the pressed pipe - the process of crimping the pipe begins not only in die 21, but also in rolling rollers 14. Meanwhile, the mandrel, while inside pipes and moving with it, with its cone falls into the region of the die 21, and by a calibrating girdle into the region of the rolling rollers 14. Under the action of the forces arising in the deformation zone, the mandrel 23 self-adjusts to the position when these forces are mutually balanced are, and retained therein as shown in Figure 2. As the pipe moves through the deformation zone formed by the die 21, the rolling rollers 14 and the mandrel 23, it acquires the shape and dimensions of the cross section of the finished pipe 10. As can be seen from figure 2, 3, 4 and 5, the pipe 3 is deformed in diameter (crimped ), mainly in the die 21, and the pipe wall receives the main deformation, rolling in the rollers 14 on the mandrel 23, i.e. there is a process of simultaneous drawing and rolling of the pipe.

During drawing-rolling, the outer surface of the pipe is abundantly washed with cutting fluid (coolant) supplied from the mill’s coolant system (not shown in the drawings), providing lubrication from the outside and simultaneous removal of heat generated in the deformation zone. Lubrication of the inner surface of the pipe and the mandrel is provided for the entire duration of the drawing-rolling portion of the technological lubricant injected during the preparation of the end of the pipe in the device 6.

The end of the finished pipe 10 emerging from the working body 8 falls between the diluted rollers of the bending and extracting device 9, then is compressed by them and moving through the supporting and bending rollers of the device to the receiving device 13. It is seen that the bending and exhaust device 9, creating an axial on the finished pipe 10 the force in the direction of movement of the pipe, on the one hand, contributes to the force pulling of the pipe 10 from the working body 8, and on the other hand, provides bending of the finished pipe 10 with the adjusted curvature. The turns thus obtained are stacked orderly in a basket 11, rotated at a predetermined speed from the drive of the receiving device 13, on which it is fixed. The turns placed in the basket form a bay 12.

The process of drawing-rolling at the NKHVPT mill continues until the last turn of the bay 2 of the billet pipe 3 passes through all the devices of the mill and ends up in the basket 11. After this, the process on the mill is stopped and to resume it, it is necessary to lay a new pipe bay on the unwinding device 1- blanks and perform the above operations in the above sequence.

The positive effect achieved when using the invention is that in the conditions of the existing production, for example, copper pipes of given volumes and nomenclature, or during the construction of a new production of these pipes, where it is planned to use the cheapest continuously cast pipe rolled into a bay, less units of both procurement and subsequent drawing equipment; more efficient (rational) use of high-speed drum drawing mills will be achieved by obtaining the most optimal workpiece for them; the total number of technological transitions upon receipt of commodity pipes will be reduced. All this taken together will reduce both the initial (investment) and subsequent operating costs.

Claims (1)

Cold drawing-rolling mill on a self-aligning mandrel of predominantly copper pipes made of continuously cast billets, rolled into coils, containing an unwinding device, a working body with a wire placed in it, a pulling unit and a receiving device, characterized in that the working body is made in the form of rolling from the drive rollers having a constant profile of the stream and forming a caliber of the outer profile of the finished pipe around the rolling axis, the bearings of the axes of rotation of the rollers are placed in a fixed housing, on which a die is fixed, while radial grooves are made in the die, and rolling rollers are placed in these grooves with a minimum clearance at the ends, and the mill is equipped with correct and setting devices installed along the drawing-rolling axis between the unwinding device and the working body, while the master devices are equipped with rollers rotatable from the drive with movable axes of rotation, which can be pressed against the workpiece pipe with adjustable force.

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