RU37959U1 - MACHINE FOR CONTACT BUTT WELDING OF HEATED Billets - Google Patents

Description

SJts-litje "

7 in 23 to 11/04

The machine for flash butt welding of heated billets.

The invention relates to equipment for flash butt welding by fusion of hot billets (blooms), intended for use in a rolling mill. More specifically, the invention relates to a noodle for automatic butt welding by fusion of hot billets (with a temperature of 1100-1200 ° C) from low-carbon and structural steels with a cross section of up to 2500 mm as a part of continuous rolling mills. The machine is installed between the heaters; the furnace and the first stand of the rolling mill.

A known machine for flash butt welding of rails, containing two tick-shaped clamping devices made in the form of hollow two-arm levers, isolated in isolation from each other on a common central axis with the possibility of movement along it relative to each other by means of bimetallic fusion-precipitation hydraulic cylinders connecting them current-carrying rods, and two welding transformers, integrated into the two-arm levers of one of the clamping tick-shaped devices, with each of the two-arm levers at one end it is connected with the rod or the housing of the clamping cylinder, and the other is equipped with clamping current-carrying shoes, and welding transformers are connected by current-carrying wires through the current-supplying part of the rods of the fusion-precipitation hydraulic cylinders with current-carrying shoes (see, for example, patent RU 2186664 C2, 7 23 K 2304 , 08/10/2002).

The known machine does not allow the welding of hot billets by reflow in the rolling mill.

The closest analogue to the proposed mapping is a machine for flash butt welding of heated billets, containing two tick-shaped clamping devices for clamping the abutting ends of the billets and their rapprochement, one of which is fixed in a fixed case, and the other is fixed in a movable case mounted with the possibility of moving relatively fixed case, and both cases with clamping devices are mounted on a movable trolley mounted to move parallel to the axis of the workpieces, and the clamp The devices are made in the form of two-arm levers mounted on separate axes and equipped with clamping current-carrying shoes mounted on

the ends of the levers facing the workpiece and in contact with the surface at the time of clamping, welding transformers connected by flexible cords with current-carrying clamping devices and two clamping devices equipped with cutters and installed between the fixed and movable bodies (see, for example, Daniel catalog on a Daniel EWR machine for welding hot workpieces, 2000).

A disadvantage of the known machine is that in it, when welding hot billets of large cross section, deformation of the ends of the billets under the action of the compression force developed by the clamping devices is possible. However, it requires additional devices to ensure alignment of the abutting ends of the workpieces.

The objective of the invention was to develop such a machine for flash butt welding of hot workpieces, which provides welding of workpieces of large cross-section (up to 22500 mm) without deformation of the ends of the workpieces to ensure their alignment.

This problem is solved by the fact that the proposed machine for flash butt welding of heated billets, containing two tick-shaped clamping devices for clamping the abutting ends of the billets and their rapprochement, one of which is fixed in a stationary case, and the other is fixed in a movable case mounted with the possibility of movement relative to the fixed cases, and both cases with clamping devices are mounted on a movable trolley mounted to move parallel to the axis of the workpieces, and clamping devices VA are made in the form of two-arm levers mounted on separate axes and equipped with clamping current-carrying shoes, fixed at the ends of the levers facing the workpiece and in contact with the surface at the time of clamping, welding transformers connected by flexible pans with current-carrying shoes of clamping devices, and two devices for removal of burrs equipped with cutters and installed between the fixed and movable bodies, in which according to the invention, the clamp-shaped clamping devices are installed so that their axis symmetry is located at an angle of 45 to the horizontal axis of the cross section of the workpieces having a square cross section, and the surfaces of the clamping current-carrying shoes facing the workpiece have recesses in the shape of the external surface of the workpiece so that at the moment of clamping the end of the workpiece these recesses cover the surface of the end of the workpiece all over perimeter, and the clamping force is diagonal on the square section of the workpiece.

Due to the execution features noted above, the clamping devices of the machine provide clamping of the workpiece with a force of up to 120 tons and do not deform the profile of the workpiece heated to. At the same time, when clamping the ends of the workpieces, alignment and calibration of the ends of the workpieces is ensured, which is very important both for the welding process and for the subsequent operation of the burr. In addition, due to the noted features of the design of clamping devices and the profile of the current-carrying shoes, the contact surface of the current supply of the welding current to the workpiece is doubled and the friction surface of quiescence is doubled, which in turn allows to reduce the “upsetting” force ratio.

Another feature of the proposed machine is that the welding transformers are fixed in a fixed housing with a clamping device. This arrangement of transformers allows you to remove the transformers from the heating zone and place them as close as possible to the current supply; to them the shoes of the clamping devices.

Another difference is that the machine has two welding transformers connected to clamping current-carrying shoes according to the secondary circuit diagram with two parallel branches.

Among the differences, it should be noted that the machine has two devices for removing the burr, one of which is installed with the possibility of reciprocating movement of the incisors in the vertical direction, and the other is installed with the possibility of reciprocating movement of the incisors in the horizontal direction.

Another difference of the machine is that the movable housing with the clamping device is equipped with two hydraulic cylinders for moving it relative to the stationary housing, and the axes of the hydraulic cylinders are parallel to the axis of the workpiece on both sides of it.

The invention is illustrated by drawings.

Figure 1 shows a schematic diagram of a machine for flash butt welding of heated billets.

Figure 2 shows a side view of the machine.

Fig. 3 shows a tick-shaped clamping device (view from the side of the cross section of the clamped workpiece).

Figure 4 shows a side view of the clamping device.

Figure 6 shows a device for removing burr complete with a clamping device.

Figure 7 presents the main stages of the welding process using the proposed machine.

The machine (see FIGS. 1 and 2) contains tick-shaped clamping devices 1 and 2, one of which (1) is fixed in a fixed housing 3, and the other (2) in a movable housing 4 mounted for movement relative to the movable housing. Both housings 3 and 4 with clamping devices 1 and 2 are mounted on a movable trolley 5 mounted with the possibility of moving parallel to the axis of the workpieces 6 and 7. The movable housing 4 of the machine is equipped with hydraulic cylinders 8 and 9, which serve as a drive for moving the movable housing 4 relative to the stationary buildings 3 (draft drive).

The machine has two welding transformers 10 and 11, mounted in a fixed housing 3, as well as two devices 12 and 13 for removal of burrs installed between the fixed and movable housings 3 and 4. Each clamp-shaped device 1 and 2 is equipped with current-conducting clamping shoes 14, which are connected with welding transformers 10 and 11 by means of flexible busbars 15. Tick-shaped clamping devices 1 and 2 are equipped with hydraulic cylinders 16 and 17, which serve to create a compressive force on the shoes 14, covering the workpiece 6 or 7. Devices 12 and 13 for the burrs are also provided with hydraulic cylinders 18 for their reciprocating movement relative to the workpiece. Moving the movable housing 4 relative to the stationary housing 3 is carried out along the guides 19 and 20 with the help of hydraulic cylinders 8 and 9. The truck 5 is equipped with an independent drive (not shown in Fig.). The machine is installed in a continuous rolling mill at the outlet of the reheating furnace 21. The workpieces 6 and 7 are moved along the rolling tables 22 of the rolling mill. The machine has electrical power equipment 23, including a circuit breaker 24 and thyristor contactors 25 and a control system 26 implemented on a programmable controller based on a microcontroller of the Siemens SAB SOC 167 series.

The tick-shaped clamping device (see Figs. 3 and 4) is made in the form of two two-arm levers 27 and 28, mounted on separate axes 29 and equipped with clamping current-carrying shoes 14, mounted on the ends of the rails 27 and 28, facing the workpiece 6 or 7 and contacting at the time of clamping with its surface. The axis of symmetry 0-0 clamping device is located at an angle of 45 ° to the horizontal axis X

cross-section of the workpiece 6 or 7 (see Fig.Z). The surfaces of the clampable current-carrying shoes 14 facing the workpiece 6 or 7 have recesses in the shape of the extruded surface of the workpiece. The blank 6 or 7 has a square section. Accordingly, the recesses on the surface of the current-carrying shoes 14 have a triangular shape so that at the moment of clamping the end of the workpiece, these recesses cover the surface of the end of the workpiece 6 or 7 around the entire perimeter of its cross section. At the moment of clamping the end of the workpiece, the clamping force is applied diagonally to the square section of the workpiece (see FIG. 3). This ensures alignment and calibration of the ends of the workpieces at the time of their clamping and rapprochement and eliminates the deformation of the hot (with temperature to) ends of the workpieces.

The machine has two welding transformers 10 and 11 connected to clamping current-supplying devices; by them, shoes 14 by means of flexible current-supplying fuses 15 according to the secondary circuit diagram with two parallel branches (see Fig. 3). In this case, the transformers 10 and 11 are equipped with switches 30 and 31 steps, allowing you to change the value of the welding current.

The machine is equipped with two devices 12 and 13 for removing the burr, equipped with cutters 32, which are mounted parallel to the outer surfaces of the workpiece 6. The devices 12 and 13 are equipped with hydraulic cylinders 18, providing their reciprocating movement. When this device 12 performs a reciprocating movement in the vertical direction, and the device 13 in the horizontal direction.

The machine operates as follows.

In the initial position, the movable trolley 5 with the fixed and movable bodies 3 and 4 fixed to it is in the extreme position close to the reheating furnace 21 of the rolling mill. In this case, the rods of the hydraulic cylinders 8 and 9 are retracted and the movable housing 4 is withdrawn from the stationary housing to a maximum distance (50 mm). The ends of the levers 27 and 28 of the clamping devices 1 and 2 are separated and the current-carrying shoes 14 are not in contact with the headers 6 and 7. The devices 12 and 13 for removing the burr are also in the initial position, in which the rods of the hydraulic cylinders 18 are retracted and the cutters 32 are removed from the workpieces.

In the initial phase (position I in FIG. 7), the housings 3 and 4 of the clamping devices 1 and 2 are accelerated by the trolley 5 to equalize (synchronize) their travel speed Vi with the travel speed V2 of the heated billets 6 and 7 on the rolling tables 22 of the rolling mill. In this case, the clamping device 1 should

be in a position with respect to the workpiece 6, in which the rear end of the workpiece 6 has a projection of 25 mm with respect to the device 1. In this position, the control system 26 sends a signal to clamp the rear end of the workpiece 6 in the current-carrying shoes 14 of the clamping device 1. After that clamping the front end of the heated billet 7, then press it; according to the live rolls from the reheating furnace (position II in Fig. 7) using clamping device 2. When clamping in clamping current-carrying shoes 14 clamping devices 1 and 2 ends blanks 6 and 7 are their simultaneous alignment.

Further (position III in Fig. 7), according to the signal from the control system 26, a fusion welding and heating cycle is performed according to a given program.

After the welding cycle, when the ends of the workpieces 6 and 7 are clamped using clamping devices 1 and 2, the burr is removed from the vertical surfaces of the workpieces using the device 12, which performs reciprocating movement in the vertical direction (position IV in Fig. 7).

Then, the device 12 is returned to its original position and the grata is removed from the horizontal surfaces of the workpieces using the device 13, which performs reciprocating movement in the horizontal direction.

After removing the burr (position VI in Fig. 7), the rods of the hydraulic cylinders 16 and 17 of the clamping devices 1 and 2 are extended to the initial position, in which the ends of the workpieces 6 and 7 are unclenched (position VII in Fig. 7) and the housing of the clamping devices 1 and 2 using a movable trolley 5 are transferred to the extreme position in the direction of the re-heating furnace 21.

The organization of the continuous rolling process using the proposed machine for welding heated billets into a continuous lash can significantly improve the quality of long products, increase productivity and controllability of the rolling process and the production line as a whole.

Claims (5)

1. A machine for flash butt welding of heated billets, comprising two tick-shaped clamping devices for clamping the abutting ends of the billets and their rapprochement, one of which is fixed in a stationary case, and the other is fixed in a movable case mounted with the possibility of movement relative to the fixed case, both cases with clamping devices mounted on a movable trolley mounted to move parallel to the axis of the workpieces, and clamping devices are made in the form of two-arm levers installed welding transformers connected on separate axes and equipped with clamping current-conducting shoes, fixed at the ends of the levers facing the workpiece and in contact with the surface at the time of clamping, welding transformers connected by flexible tires to the current-carrying shoes of clamping devices, and two devices for removing the burr, equipped with cutters and installed between the fixed and movable cases, characterized in that the clamp-shaped clamping devices are installed so that their axis of symmetry is located at an angle of 45 ° to the horizontal axis the cross section of the workpieces having a square cross section, and the surfaces of the clamping current-carrying shoes facing the workpiece have recesses in the shape of the external surface of the workpiece so that at the moment of clamping the end of the workpiece, these recesses cover the surface of the end of the workpiece around the entire perimeter of its cross section, and the clamping force is applied diagonally square section of the workpiece. 2. The machine according to claim 1, characterized in that the welding transformers are fixed in a fixed housing with a clamping device. 3. The machine according to claim 2, characterized in that it has two welding transformers connected to clamping current-carrying shoes according to the secondary circuit with two parallel branches. 4. The machine according to claim 1, or 2, or 3, characterized in that one of the devices for removing grata is installed with the possibility of reciprocating movement of the incisors in the vertical direction, and the other is installed with the possibility of reciprocating movement of the incisors in the horizontal direction. 5. The machine according to claim 4, characterized in that the movable body with a clamping device is equipped with two hydraulic cylinders for moving it relative to the stationary body, and the axis of the hydraulic cylinders are parallel to the axis of the workpiece on either side of it.