Arc-laser module for orbital welding of fixed ring pipe joints

FIELD: machine building.

SUBSTANCE: module comprises a guide belt, a movable orbital carriage mounted on the guide belt and able of travelling along it. The carriage includes a longitudinal movement drive and a moving device consisting of a carrying roller system and a gear wheel. A joint monitoring sensor, a welding wire reeling device and a handler are installed on the carriage. The handler consists of two mutually perpendicular linear guides with motors, which can move in respect to each other. The transverse linear guide is equipped by a laser welding head, a wire feeding unit, an arc welding torch, a video camera and a controller.

EFFECT: invention allows for the increase of productivity and efficiency of welding process for fixed ring pipe joints and for the improvement of welded joint quality.

3 cl, 3 dwg

 

The invention is intended for automatic welding and welding of circumferential joints of complex steel structures based on modern and advanced steel implements technology laser and laser-arc automatic welding in the construction of pipelines of various types, the manufacture of pressure vessels, special building structures and cladding of metal on the surface of parts.

Known laser system for welding pipes [RU patent No. 2165344]. The complex is placed on the platform and includes an Autonomous power plant, control system, store and process the laser. The welding head is made standalone and includes a rotary mirror, a focusing lens device for gas protection of the weld, a mobile unit with wheels, a tank of shielding gas and a local control system. Between the process control system of the laser and the local control system of welding head there is an optical connection. The disadvantage is that the welding is performed using a laser, which reduces the efficiency of the process and increases the requirements for the preparation of edges for welding. Also a disadvantage is that is used as part of a complex WITH2the laser, which greatly complicates the system of transportation of laser radiation in the WA�in welding.

Known orbital holder containing at least two interconnected element in the form of a ring segment; a device butt welding pipes to form a pipeline that contains such holder [RU patent No. 2441738]. Orbital holder contains at least one welding carriage, which is equipped with at least one weld head, containing a welding burner, and is capable of translational movement along the formed pipe and the positioning of the welding device along the plane of the joint between the welded pipes. The disadvantage of this device is the fact that orbital welding holder is a complex structure and can be used only under a certain size welded pipes. Also a disadvantage of the device is only used arc welding that does not provide a high performance position butt welding of pipes.

Known orbital welding device for the construction of pipelines, selected as a prototype [RU patent No. 2355539]. The device includes adjustable relative to the first pipe end and the annular junction of the guide wrap and orbiting the cart. Orbital carriage can be moved along the guide wrap with motor pic�edstam feeder. On the orbital carriage mounted laser welding head for maintaining and forming the laser beam. The laser welding head is made with the possibility of orientation on the ring junction. High-power fiber laser installed with damping of oscillations at a distance from the laser welding head, in particular on a vehicle moving along the axis of the pipe outside the pipe and is connected with the cooling system. Laser MSG arc welding head mounted on truck with orbital capability, in particular, orbital movement relative to the truck in several directions. The laser welding head mounted nozzle for supplying a process gas in the area of laser welding. The orbital truck on the other side of the laser welding head mounted means for supplying wire to the zone of laser welding. The wire is fed from a placed on the vehicle unit wire feeder for wire feed line connected to the orbital carriage. For heating of the wire immediately before the tool is provocatively block. Management and control of the entire welding process takes place via the management VM, which via the communication line is in communication connection with the sensors and the Executive bodies of the orbital�Oh truck, the location of components and vehicle units. In administering VM provides a means of logging through the management VM associated with the weld quality sensor for storage and optical playback recorded images of the weld, so that after the implementation of the welding process may repeat shot of the welding process. The device comprises a control unit, the welding process and the weld. The carriage includes a base, a conveyor and a bracket.

A disadvantage of the device is that its design does not provide high-quality welds without presenting specific requirements for the preparation of edges for welding and providing a gap at joining ends of the pipes, namely: not more than 1 mm, preferably less than 0.3 mm, particularly preferably technical zero clearance, which entails additional labor costs for preparation of the edges of pipes and their subsequent alignment, impacting ultimately on the productivity and efficiency of welding operations.

The task is to increase the productivity and efficiency of the welding process fixed annular pipe joints, improving the quality of the welded connection.

For solving the proposed module laser-arc orbit for�encourages creativity welding rigid annular pipe joints (module). The module includes a belt guide mounted on the workpiece (pipe), a movable orbital carriage mounted on the belt is movable along a guide belt. The carriage includes drive longitudinal movement and displacement device, which consists of a system of load-bearing rollers and gears. System of load-bearing rollers and a toothed wheel mounted on the lower plane of the base of the carriage. The carriage is equipped with a sensor for tracking the joint, bracket and motorized take-up device of the welding wire. In addition, the carriage is mounted manipulator, which consists of two mutually perpendicular linear guides - transverse and vertical, equipped with motors and moving relative to each other. Transverse linear guide is moved in two directions relative to the vertical guide - vertically, along the axis of the vertical guide and transversely perpendicular to the welding seam. Vertical linear guide is fixed on its base on the bracket. On transverse linear guide installed head laser welding by means of a bracket, node, wire feed, torch welding arc, CCTV camera and controller. The burner is mounted for adjustment of its position progressive IPO corner in the longitudinal and transverse planes of the seam of a welded joint. On one of side surfaces of the guide belt has teeth that mesh with the toothed wheel of the carriage. The longitudinal displacement drive of the containing, for example, a motor and gearbox, drives the toothed wheel being engaged with the belt guides leads to the movement of the carriage. The laser welding head mounted for orientation on the ring junction. The drive of the feed unit wire sets in motion a system of rollers that move the welding wire on the coil, mounted on the axis of the motorized take-up device of the welding wire. Wire is fed to the welding gun, the front of the laser beam in the direction of motion. Sensor tracking the joint in the welding process monitors the welding joint of pipe in order to adjust the position of the laser weld head and torch welding arc relative to the weld joint. Sensor tracking the junction, for example, triangulation scanner that scans a laser beam the surface of the metal in a pulsed mode. After processing, the signals are fed to a controller which outputs control signals to the motors located on linear guides. Surveillance camera transmits the video image from the welding zone on the monitor control rack, which has�I at a distance from the module.

Belt guide may be formed as a flexible (belt) belt guide with the possibility of separation.

During operation of the module the required high-power fiber laser, a source of welding current, complex compressor equipment, air preparation unit and distribution of gases and the control rack containing the host PC. All elements can be mounted on the vehicle, may be located in a separate room or in close proximity with the workpiece.

The guidance system of the module, consisting of a sensor for tracking the joint of the manipulator and control process makes it possible to weld without special edge preparation and the possibility of obtaining high-quality welded joints with a gap between the ends of pipes up to 2 mm, which is proven to increase performance and efficiency of hybrid laser-arc orbital welding rigid annular pipe joints. In addition, the sensor monitoring the joint in conjunction with the manipulator and the control unit of the process allow to work not only inaccuracies Assembly design in welding of a stationary annular pipe joints, but a more complex path of the welding seam welding object.

The use of the device for moving the carriage can speed laser-arc welding d� 3 m/min to obtain high-quality welds, which increases the efficiency of the welding process of hybrid laser-arc welding of non-rotating annular pipe joints while maintaining the quality of the welded connection. Only a set of distinctive features allows to solve the task Module laser-arc orbital welding rigid annular pipe joints guide contains a belt with teeth 1, a movable orbital carriage 2 mounted on the belt 1. The carriage 2 includes a longitudinal displacement drive of the 3 and the displacement device, which consists of a system of load-bearing rollers 4 and the toothed wheel 5. System of load-bearing rollers 4 and gear 5 mounted on the lower base of the carriage. On the carriage 2 is provided with a sensor for tracking the joint 6, the bracket 7 and motorized take-up device of the welding wire 8. In addition, the carriage 2 via a bracket 7 is mounted to the manipulator 9, which consists of two mutually perpendicular linear guides 10 and 11, provided with motors 12, 13 respectively. On transverse linear guide 10 installed head welding laser 14 by means of a bracket 15, the feeder wire 16, the burner welding arc 17, the device of the video camera 18 and the control unit by the process controller 19. Feeder wire 16 consists of a system of rollers 20 and the drive of the feed unit surface�Ki 21 and mounted on the manipulator by means of an arm (Fig.1, 2, 3).

Before welding on the pipe install the module laser-arc orbital welding rigid annular pipe joints. Initially the tube is set up on belt guide 1. On belt guide 1 install the carriage 2 so that the toothed wheel 5 movement device engages with the teeth of the guide belt 1 and the side surface of the guide belt in the slots of the load-bearing rollers 4. Set the following parameters: the laser power is set equal to 10 kW, the power of the arc is equal to 8 kW, welding speed: 2 m/min. run of the welding process. The actuator longitudinal movement of the carriage 3 from the electric motor through a reduction gear transmits torque to the toothed wheel 5, which being in mesh with the teeth of the guide belt 1 moves the carriage 2. The radiation of high-power fiber laser via fiber optic cable is transported to the laser welding head 14 mounted by means of a bracket 15 on the rocker 9. Welding wire through a system of rollers 20 by means of a drive unit of a wire feeder 21 is extruded from the motorized take-up device of the welding wire 8 and is supplied to the burner welding arc 17. Welding wire during the welding process is located before the laser beam during its movement. Head laser welding 14 equipped�on the cross jet, which is fitting for the compressed air. Through the nozzle in a cross-jet laser welding head 14 is supplied with compressed gas, which provide protection to the laser welding head 14 from the welding process. The welding torch 17 is equipped with a nozzle for supplying a mixture of shielding gases. In the area of laser-arc exposure serves a protective gas mixture consisting of an inert (Ar) and active (CO2gases in a percentage of 80% and 20% respectively in the amount of 25 l/min a Mixture of gases is fed through the nozzle welding torch 17. A tracking sensor for junction 6, for example, triangulation scanner that scans a laser beam the surface of the metal in a pulsed mode and in the welding process monitors the junction of the pipes. Diffuse the reflected signal is transmitted through the optical system of the CCD matrix, included with the scanner. Data from the sensor are processed by a microprocessor module that is included with the scanner. On the basis of a received signal is formed an array of data defining the profile of the scanned surface. Data is received at the control computer included in the control rack. After data processing control computer generates commands to a controller which outputs control signals to the motors located on linear guides, and thereby corrects the position of the laser welding head 14 and mountains�LCI welding 17 welding joint.

Welding is carried out in two steps. The first reception - clockwise from the 12 o'clock position to the 6 o'clock position. After first taking a welding laser welding head 16 to outweigh the implementation of the second admission. The second method is carried out with the 12 o'clock position to the 6 o'clock position counterclockwise under the same conditions. In the initial position of the welding torch 17 mounted at an angle of approximately 30° relative to the laser beam. In the process of welding angle of the welding torch 17 changes smoothly. The adjustment of the angle of inclination of the welding torch 17 relative to the laser beam allows to hold the molten bath from escaping from the outer surface of the welded samples. CCTV camera 18 translates the video image of the welding zone on the monitor stand management for visual inspection. Thus, the welding of a stationary annular pipe joints.

The application module laser-arc orbital welding rigid annular pipe joints allows you to:

- to improve the performance and efficiency of the welding process by reducing the requirements for the preparation of products edges for welding to the values achievable at the present level of production;

- to improve the quality of the welded joint due to the tracking of the pipe joint and the adjustment provisions, laser and plasma guns.�th welding heads and welding torch relative to the weld joint;

- to obtain a welded joint of tubular specimens with wall thickness up to 16 mm in one pass with thermodynamic efficiency of the welding process >40%.

The use of flexible belt guide allows the welding process not only for billet-pipe, but also more complex three-dimensional structures, such as the hull of a ship, the hull of the submarine, it is also possible by welding vertically, which makes the module more versatile.

1. Module for orbital laser-arc welding of non-rotating annular pipe joints containing a belt guide, a movable orbital carriage mounted on the belt is movable therealong by means of a movement device, a sensor for tracking the seam laser welding head, arc welding gun, mounted on the carriage of the manipulator with motors to move the laser welding head and the arc welding torch relative to a welded joint, motorized take-up device of the welding wire, the surveillance device, the control unit of the welding process and the feed unit wire, wherein that the displacement device made in the form mounted on the base of the carriage system of load-bearing rollers and gears, and the arm consists of two mutually perpendicular linear�'s guide with engines is arranged to move relative to each other, with motorized take-up device of the welding wire is attached to the base of the cradle and on the basis of transverse linear guide installed laser welding head, a knot in the wire feed arc welding torch with adjustable position angle, the surveillance device and the control unit of the welding process.

2. The module according to claim 1, characterized in that the belt guide is made in the form of a flexible belt guide belt with the possibility of separation.

3. The module according to claim 1, characterized in that the control unit of the welding process is executed in the form of the controller, and the surveillance device is in the camera view.



 

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EFFECT: higher quality of cutting.

4 cl, 8 dwg

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