RU2323073C1 - Flash welding set, welding head and its travel mechanism - Google Patents

Abstract

FIELD: mechanical engineering; butt welding.

SUBSTANCE: invention relates to equipment for resistance butt welding of girth butt joints of larger diameter pipes when laying main pipelines. Proposed set contains control station, rod and welding machine. Said machine consists of two-speed transfer case, mechanism to provide travel of machine inside pipe, pumping station, flash trimmer and welding head. Travel mechanism is made in form of three-arm support on which two reduction gears paired and unities in one welded housing are uniformly hinge-mounted over circumference on cheeks. Reduction gears are driven by two-speed transfer case. Welding head is coupled with travel mechanism through two-speed transfer case and pumping station, and it contains central hollow tube, welding transformer, clamping and upsetting trolleys, two-piece levers, steel and conducting cover plates. Clamping and upsetting trolleys are made for sliding along central hollow tube. Two-piece levers are arranged uniformly spaced over circumference of hollow tube on each trolley and are connected to each other. Steel and conducting cover plates are secured on levers and are connected by flexible buses with welding transformer.

EFFECT: increased capacity, reliability of set, enlarged functional capabilities at connection of long length articles, increased labor efficiency.

4 cl, 4 dwg

Description

The invention relates to equipment for flash butt welding of annular pipe joints in the construction of main pipelines and stationary welding conditions and is intended for flash butt welding by continuous fusion of individual insulated and uninsulated pipes or pipe sections with a large bore

The prior art apparatus for butt welding of pipes containing a stationary expandable clamp and a movable expandable clamp, clamping elements and drive cylinders designed to install pipes for welding relative to the apparatus. The cylinder makes an axial movement of a movable expanding clamp to connect the ends of the pipes (US 4323752, 04/06/1982).

A known machine for flash butt welding of pipes, comprising a device with a clamping mechanism for pipes, a puller, a fusion and precipitation drive and a self-centering device located in the housing with support and drive rollers and a spring mechanism for driving the drive rollers to the pipe, is rigidly connected to the rod of the power cylinder. The self-centering device is equipped with at least three three-arm levers, the rolling axes of which are arranged uniformly in the circumference of the housing, a drive roller of a self-centering device is installed on one of the arms of each lever, a support roller of the self-centering device is on the other, the rod of the power cylinder is rigidly fixed to it a disk pivotally connected to the third shoulder of each three-arm lever (SU 938488, 11/30/1983).

Closest to the proposed invention is a machine for flash butt welding of pipes, comprising a central rod with two supporting disks, fixed and movable clamps of the pipes to be welded with centering elements and spacer disks mounted to move along the rod from power drives, a fusion and precipitation drive, fixed on one of the supporting discs and connected to the housing of the movable clamp. The spacer discs of the movable and fixed clamps are equipped with roller bearings, the housing of the movable clamp is made in the form of a clip with roller bearings, and the centering elements are made in the form of levers with earrings that articulate them with spacer discs. The levers of the movable clamp are pivotally mounted on the cage, and the levers of the fixed clamp are on the second support disk (SU 818788, 04/07/1981).

The disadvantage of these devices is that:

- displacement reducers during the burr cut do not withstand the load (the worm gear fails);

- there is no installation speed in the movement mechanism;

- the filler is not fixed and cuts into the body of the pipe;

- the clamping lever with steel shoes is not fully pressed against the body of the pipe, which leads to slipping of the welding machine;

- a sectional welding transformer is used, which often fails.

The problem to which the proposed invention is directed is to create such a unit by fusion welding with a welding head and a movement mechanism that would eliminate the above disadvantages.

The technical result achieved by the implementation of this invention is to increase labor productivity, reliability, reduce labor costs and expand the functionality when connecting long products.

The specified technical result is achieved in the installation for fusion welding of pipes containing a control station, a rod and a welding machine, consisting of a two-speed transfer case, a movement mechanism for moving the machine inside the pipe, made in the form of a three-beam support, on which the cheeks are uniformly mounted around the cheeks two gearboxes paired and combined in one welded case, the drive of which is carried out from a two-speed transfer case, pump station, filler and welding heads connected through a two-speed transfer case and a pump station with a moving mechanism and containing a central hollow pipe, a welding transformer, clamping and upsetting trolleys made with the possibility of sliding along the axis of the central hollow pipe, two-part levers arranged uniformly around the circumference of the hollow pipe on each of the carts clamping and upsetting and pivotally connected to each other, and steel and conductive plates fixed on levers, connected by flexible tires to the welding transformer.

The welding transformer is made toroidal.

This technical result is achieved in a welding head for fusion welding of pipes containing a central hollow pipe, a welding transformer, trolleys of clamping and draft, made with the possibility of sliding along the axis of the central hollow pipe, two-part levers located uniformly around the circumference of the hollow pipe on each of the trolley clamping and precipitation and hingedly connected to each other, and steel and conductive plates fixed on levers, connected by flexible tires to the welding transformer.

The aforementioned technical result is achieved in the movement mechanism of the welding machine for fusion welding of pipes, made in the form of a three-beam support, on which two reducers paired and combined in one welded case are pivotally mounted on the cheeks uniformly.

The invention is illustrated by drawings, where figure 1 shows a General view of the welding machine; figure 2 - rod; figure 3 - welding head; figure 4 - movement mechanism.

The fusion welding apparatus comprises a control station (not shown), a welding machine 1, and rods 2.

The operation of the welding machine is controlled through a remote control and a stationary control using equipment installed in a control station containing a 100 kVA diesel power station designed to power control circuits, electrical equipment necessary for automatic control of welding modes, installation movement, as well as cable communications, connecting the control station with the welding machine 1.

The welding machine consists of assembly units: a welding head 3, a pumping station 4, a two-speed transfer case 5, a moving mechanism 6 and a removal device 7.

The main bearing element of the welding head 3 is the central hollow pipe 8, inside of which there are electrical and hydraulic communications of the welding machine. Mounted on the outer surface of pipe 8: back support 9, clamping trolleys 10, welding transformer 11, upset cart 12 and front support 13. Supports 9 and 13, as well as welding transformer 11, are mounted rigidly relative to pipe 8.

Clamping carts 10 and draft carts 12 move, slide along the axis of the pipe 8. Clamping cylinders 14 are rigidly fixed on clamping carts 10, the rods of which are respectively connected to the back support 9 and draft box 12. The draft cart 12 is connected to the stocks of upset cylinder 15, which are fixed on the front support 13. Clamping carts 10 using earrings 16 and axles are connected with levers 17, which are opposite hinged ends are pivotally connected respectively to the backrest 9 and the draft carriage 12. Each carriage 10, 12 carries eighteen levers at 17, arranged uniformly around the circumference. Steel pads 18 and conductive pads 19 are attached to the levers, which are connected with a transformer 11 by flexible busbars 20. The levers 17 are made of two components and pivotally connected by a hinge 27 to each other to increase the pressure of the welding machine 1 on the pipe being welded and to prevent slipping of the machine being welded 1 to be welded pipe during an upset.

Pumping station 4 consists of a compartment housing, which is hermetically divided into two parts, the right side is the hydraulic tank and the left, which houses the pumping unit and two electric motors (displacement motor and cruising speed electric motor) of a two-speed transfer case 5.

A two-speed transfer case 5 serves to reduce revolutions and transmit the rotation of electric motors by a worm gear 23 and has two speeds:

- installation speed - the electromagnetic clutch is engaged, when connecting the installation speed displacement motor with a planetary gearbox, the general gear ratio is i = 27;

- cruising speed - the electromagnetic clutch is disconnected, the cruising speed electric motor is operating, the general gear ratio is i = 2.2.

The movement mechanism 6 is used to move the machine along the axis. The supporting element is a cross 21, made in the form of a three-beam support and on which three gears 23 are single-worm and have a gear ratio i = 32 and are made in the form of two paired gears combined in one welded case evenly around the cheeks 22. A drive wheel 24 is installed on each shaft of the gearbox 23 (there are four of them in the gearbox), which is mounted on a cone to facilitate installation and repair. The emergency preload of the gear 23 to the welded pipe is carried out by springs (not shown). The working pressure of the gears 23 to the welded pipe is carried out jointly by springs and a hydraulic cylinder (not shown). The gearbox 23 is driven from a two-speed transfer case 5 by a cardan shaft. On the crosspiece 21 are also placed three rollers 25, which serve as a support for the welding machine 1 during the plant and its withdrawal from the welded pipe.

The rods 2 are attached to the welding machine 1, depending on the length of the pipes being welded. Inside the rods 2, cables are laid through which the power and control of the equipment installed in the front hydraulic compartment 26 of the welding machine 1 are provided.

The fusion welding machine performs flash butt welding by continuous fusion in semi-automatic mode of individual insulated and uninsulated pipes or pipe sections up to 36 m, with a diameter of 1420 mm into a continuous pipe thread.

A flash welding unit performs the following operations:

alignment and welding of pipes, removal of internal burrs, own movement inside the pipe (whip).

Welding machine 1 is started inside the welded pipe using the remote control station. Set the installation speed in a two-speed transfer case 5, not reaching the edge of the pipe 40-50 mm, and clamp the clamping carts 10. When oil is supplied to the clamping cylinders 14, the clamping cart 10 moves along the pipe 8. The earring 16 assumes a vertical position and is pressed by steel plates 18 and conductive plates 19 of the levers 17. The next pipe to be welded onto the rod 2 and then fed to the pipe in which the welding machine is located 1. Then, the cables are connected from the control station to the head of the rod 2 and alignment is made. The voltage is supplied to the toroidal welding transformer 11, while it is necessary to monitor the oil pressure. Then there is the melting of the first stage, the melting of the second stage, forcing, sediment, holding under current, forging. All these operations are carried out from the control station.

Unloading, returning the draft, returning the movable carriage is carried out using the movement mechanism to cut off the internal burr at the cruising speed, the pickup knife 7 is lifted automatically from the control station. Moving from joint to joint by the movement mechanism is performed at marching speed from the remote control.

The welding time is 10 minutes, that is, the time spent on all operations takes 10 minutes from the joint to the pipe joint.

Installation completely eliminates manual welding.

Claims (4)

1. Installation for welding pipes by reflow, characterized in that it contains a control station, a rod and a welding machine, consisting of a two-speed transfer case, a movement mechanism for moving the machine inside the pipe, made in the form of a three-beam support, on which it is articulated uniformly around the circumference on the cheeks fixed on two gearboxes paired and combined in one welded case, the drive of which is carried out from a two-speed transfer case, pump station, filler and welding head, connected through a two-speed transfer case and a pumping station with a moving mechanism and containing a central hollow pipe, a welding transformer, clamping and upsetting trolleys made with the possibility of sliding along the axis of the central hollow pipe, two-part levers arranged uniformly around the circumference of the hollow pipe on each of the clamping carts and precipitation and hingedly connected to each other, and steel and conductive plates fixed on levers, connected by flexible tires to the welding transformer. 2. Installation according to claim 1, characterized in that the welding transformer is made toroidal. 3. A welding head for fusion welding of pipes, characterized in that it contains a central hollow pipe, a welding transformer, trolleys of clamping and draft, made with the possibility of sliding along the axis of the central hollow pipe, two-part levers arranged uniformly around the circumference of the hollow pipe on each of the bogies clamping and upsetting and pivotally connected to each other, and steel and conductive plates fixed on levers, connected by flexible tires to the welding transformer. 4. The movement mechanism of the welding machine for fusion welding of pipes, characterized in that it is made in the form of a three-beam support, on which two reducers paired and combined in one welded gear case are pivotally mounted on the cheeks uniformly.

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