SU903036A1 - Head for automatic welding of tube non-rotary butts - Google Patents

Description

(5) HEAD FOR AUTOMATIC WELDING

PIPE JOINTS

I

The invention relates to automatic welding joints for closing the pipe joints with a non-consumable electrode without feeding filler wire using jet protection with inert gases and can be used in various fields of engineering.

A device for welding fixed pipe joints is known, comprising a housing, a faceplate for fixing a welding head thereon, and a protective gas supply system to the welding zone P. The protective gas supply system is designed as a channel in the body of the faceplate, in the center of which there is a backwater, and the latter is mounted the upper elastic wall of the channel, and the protective gas supply valves into the channel cavity, made in the form of rigid rods with spring-loaded cups, while at the lower ends of the rods there are fixed two-sided rollers, interacting Suitable

flanges with the edges of the flexible outer channel wall.

Such a device provides a hoseless supply of protective gas to the welding zone and protection of the weld.

The disadvantages of the device include the complexity of the design of the gas supply system, in which due to the inadequate reliability of the supply of inert gas to the burner there are large leaks.

10 gas to the atmosphere on the bevels of the upper elastic wall at the faceplate cut-out. This is explained by the fact that one of. gas supply channels, reaching its bevel glass, overlap

15 by the valve not immediately, but gradually in the process of moving under it, and completely failing only after the glass has passed the entire bevel. Consequently, in the process of the movement of the stationary gas inert gas through this valve does not flow into the gas table of the faceplate, but disappears into atmosphere, as when purging, and a smaller amount of inert gas enters the burner only through the second valve, which degrades the quality of the weld due to the uneven supply of protective gas. In addition, the quality of the weld deteriorates due to the inevitable air leaks in the area of the glasses of gas supplying systems, since each glass is in contact simultaneously with an elastic upper wall and lateral protrusions of the gas channel of the faceplate, there are constructive gaps in the joints of the latter, which are associated with the external environment (atmosphere) through which there is an underlayer of air in the gas channel of the faceplate. A device for welding fixed pipe joints is known, comprising a stationary body in which current supply brushes are mounted, a welding torch mounted on a C-shaped faceplate with a current bus, a removable liner and a drive for rotating the faceplate, and the removable liner is provided with an additional current bus

connected to the current bus C-shaped faceplate 23.

A device of this design has reduced dimensions. In addition, reliability in its operation is improved by eliminating the possibility of arcing and welding current losses, which leads to an increase in the quality of welded joints.

The disadvantages of the device include the design complexity of a hoseless current lead and the absence of a hoseless system for supplying protective gas to the arc zone.

In such a device, only a hose system for supplying inert gas to the welding zone is possible, and with this design of the gas supply, the rods are wound onto the pipe during welding, impairing the view of the welded joint. As a result of winding up the hoses, torch movement may be retarded, which leads to a deterioration in the quality of the welded joint. At the end of the welding process, in order to remove the device from the welded joint, it is necessary to rotate it in the opposite direction to unwind the hoses. This complicates the maintenance of the device and reduces productivity. 8 of the greatest degree, these drawbacks are manifested in the multipass weld, ke of thick-walled pipes. 9

Inert gas is supplied to the welding zone, which contributes to the protection of the weld, allows welding pipes of several sizes 0 with diameters, for example, from 12 to

30 mm, due to the presence of three replaceable g-washers, replaceable liners and replaceable burners, it is compact and easy to use.

5, its disadvantages include the fact that during welding, the worm gear in the main annular gas collector gas in the exit zone of the gas-supplying faceplate channel due to the presence of a constructive gap between the end and the worm gear, air is sucked in, which degrades the quality of the weld. In addition, after welding several joints (three-meti5 pex), the faceplate is strongly heated by the high temperature of the welding arc, and this leads to an increase in the gap between the faceplate and the worm gear, makes it difficult

0 rotation of the latter. It is necessary for some time (min) to stop welding the subsequent joints, allowing the faceplate to cool, otherwise the life of the welding head is reduced and the quality of welding deteriorates. The weld zone at such a head is open, and the air from the atmosphere oxidizes the weld. 64. Also known is a head for automatic welding of non-rotating pipe joints, closest to the invention, comprising a faceplate, including a body and a base, in which a gas supply channel is made and a catch with an insert and a retainer is placed, a worm wheel consisting of two half-rings, in one of which the main collector gas channel is made, a burner containing two half rings, one of which is rigidly connected with a half ring of a worm gear with a main gas channel. a replaceable nozzle and a tungsten electrode are located, and the other half ring is rigidly connected to the second half ring of the worm wheel and the drive, kinematically connected with the C 33 worm wheel. Such a head has a simple and reliable hoseless electrical power supply system and a simple hoseless gas supply system that provides the well-known the insertion in the faceplate guides and its quick removal are not secured, and this, together with the time lost to cooling the faceplate, significantly increases unproductive losses in the overall welding cycle, lowers productivity. The disadvantages of such a head are that it also carries the fact that each faceplate is designed to weld only a limited range of diameters of the pipes to be welded (12-18; iS-Zt; mm), and this reduces the technological capabilities of the welding head. The aim of the invention is to improve the quality of welding and productivity. is achieved by the fact that in the head for the automatic swirl of non-rotating pipe joints containing a faceplate, including a housing and a base in which a gas supply channel is made and a gripper is placed: with an insert and a retainer, a worm wheel, consisting of two half rings, in one of the which the main collector gas channel is made, the burner containing two half rings on one of which, rigidly connected to the half ring of the worm gear with the main gas channel, rigidly fixed a replaceable nozzle and a tungsten electrode, and the other half ring rigidly connected with the second half-ring of the worm gear and the branch, kinematically connected with the worm gear, in the latter from the outer diameter of the main collector gas channel there is an additional collector gas channel and a hole connecting it to the gas feed plate of the faceplate, and the front the surfaces of one of the half-rings of the worm gear, and the surfaces of the worm gear, which are in contact with the faceplate, are provided with a sealing strip made of a thermo-resistant plastic material with antennae at the edges of the additional and main gas collector channels. The washer is made with a C-shaped cooling channel and is equipped with tubes for the supply and removal of coolant. In order to increase the intensity of the heat sink, the cooling channel is equipped with a C-shaped spring with a square cross section of the turns, and the coolant outlet pipe is equipped with a spring with a square cross section and the winding direction opposite to the direction of the turns of the cooling spring of the cooling channel. coolant outlet at an acute angle to the end of the cooling channel. The burner is equipped with replaceable covers, made in the form of half-rings made of electrically insulating, heat-resistant material, and the replaceable covers of the burner are made in the form of protective light filters made of quartz glass. In order to provide a quick fict. Inserting the insert in the base of the faceplate, the insert retainer is made in the form of a bar and a glass with a spring-loaded ball mounted to interact with the insert made with a bevel for the latter, with one end of the bar fixed on the base of the faceplate hingedly, and the other the driving screw. FIG. 1 shows a general view of a welding head; in fig. 2 - section aa of FIG. in fig. 3 is a view along arrow D in FIG. in fig. k - fastening replaceable burner covers; in Fig. 5, node I in Fig. 2; figure 6 section bb in figure 2; Fig.7 section bb In fig.Z; on Fig - section GG on fig.Z. The welding head consists of a faceplate with a fixed base 1 and a drive 2, which is an electric motor with a planetary gearbox. In the body of the base 1, a gas supply channel 3 is made and a C-shaped grip k of the insert 5 is placed. The latter is installed in the guide rails of the base 1 with radial movement and provides the grip on the welded pipe using the grip k. The insert insert 5 is made in the form of a bar 6 with a cup in which the spring 7 and the ball 8 are located, mutually acting with an insert S, made with a bevel 9 for the latter. One end of the bar 6 is hinged to the base 1 by means of a screw 10, and the other is made with a slot for of a tapering screw 11, also installed on the base 1. Based on 1 face plate, a sliding worm wheel, made of insulating material in the form of two semirings 12 and 13, is mounted with a main annular gas collector channel 1 and an additional annular manifold gas channel 15 located on a larger diameter with respect to channel I, having a smaller section than the main one and connected to channel 3 in the base 1 of the faceplate by hole 16. The welding head's torch is also made of two Lets 17 and 18 which function as a bus bar. In the semicircle 17, the burner is fixed with screws 19, the replaceable nozzle 20, with the aid of screw 21 — a tungsten electrode 22 and a metal mesh 23 is placed. The semi-ring 17 of the burner is rigidly fixed with screws 2k and pins 25 on the outer plane of the semi-ring 12, in which the gas opening is performed 26, connected to the chamber 27 of the half ring 17, and the half ring 18 of the burner is also rigidly fixed with screws 24 and pins 25 on the outer plane of the half ring 13. Fixed half rings 17 and 18 are interconnected by means of connecting pins 28, hook 29 and springs 30 which are arranged in a C-shaped channel of the burner. The end surfaces of one of the half-rings, for example 12, the worm gear, as well as the outer surface of the half-rings 12 and 13, in contact with the plate 31 of the base 1, are equipped with a sealing gasket 32 made of a heat-resistant plastic material that has channels 14 and 15 at the edges. 33. As a sealing, heat-resistant, ductile material, for example, a composite material based on polytetrafluoroethylene, for example FGD-8-7, fluoroplastic-4D, etc. or a synthetic adhesive with a filler or plasticizer, depending on brittleness of the adhesive film. A suspension, for example, fluoroplast-4D is applied directly to the above-mentioned surfaces, followed by thermal treatment or a finished film, for example, from 0GD-8-7 or fluoroplast-4 is glued to these surfaces. Composite materials based on 9.6.88 fluoroplast, as well as Fluoroplastic itself (its suspensions or films), for example, fluoroplastic Hell, possess the necessary plasticity and heat resistance, good sliding and are completely safe during operation. Synthetic glue as a sealing film is also applied directly to the above surfaces. If the selected adhesive has a brittle film, then it is necessary to add a plasticizer to it, bringing the adhesive film to the required plasticity and maintaining the required heat resistance. Conversely, if the selected adhesives have low heat resistance and are too plastic, then it is necessary to add a filler to it, which contributes to increasing its heat resistance and reducing plasticity. In the course of long-term operation, as the sealing film wears out (wear out), it is restored, i.e. apply sealing coating again. The thickness of the sealing film can be from 0.615-0.020 mm to 0.10, 3 mm. In the body of the base 1 of the faceplate, a C-shaped cooling channel 3 is made with 35.36 tubes for supplying and discharging coolant, which is equipped with a C-shaped spring 37, which has a square cross-section and a different pitch of turns on large and smaller diameters: on a large diameter step of turns t, and on the smaller one - t, with t, tg. The channel 34 with screws 38 is hermetically sealed with a lid 39 provided with a gasket 40. The outlet tube 36 is equipped with a spring 41 s. square section and direction of turns, opposite to the direction of wigs of spring 37 of channel 34, and located at the exit as well as tube 36 at the entrance, at an acute angle, to channel 34. Semi-rings 17 and 18 of the burner are equipped with interchangeable corners 42, made in the form of semirings made of electrically insulating, heat-resistant material and fastened in semirings 17 and 18 with screws 43. The covers 42 are made in the form of protective filters made of quartz glass. The joint of these covers between them is made at an acute angle of the end surfaces. The base 1 is rigidly connected to the housing 44, which is fixed

drive 2 of the faceplate with a screw C, interacting with a worm wheel made of two half-rings 12 and 13.

An isolator torL7 is fastened to the housing k with a screw 46, in which a spring-loaded collector current lead brush C8 is placed, connected to the current lead 9 and cooperating with the burner.

If necessary, the brush 8 can be made water-cooled (not shown in the figures).

The grip k of the insert 5 moves from the screw 50. The faceplate is equipped with interchangeable inserts 51, which are fixed in the base 1 and in the insert 5 by screws 52.

The force of the preload of the ball 8 retainer insert 5 is regulated by a screw 53

The base 1 has a bracket 5 for setting the welding head, if necessary, in a stationary position.

Head for welding works as follows.

Liners 51, corresponding to the diameter of the pipe being welded, are fastened in the base 1 of the faceplate and in the insert 5. The burner half-ring 17 inserts the required nozzle 20, hours, and both half-rings 17 and 18 contain protective covers 42, which also correspond to the diameter of the pipe being welded.

Insert 5 with a fixed liner 51, and one of the half-rings consisting of a helical half-ring, for example, 12 and a half-ring burner,. for example, 17, taken out of the faceplate. And the second half ring, which also consists of a black half ring, for example, 13 and a half ring of the burner, for example, 18, is located in the slide of the base 1 opposite its cutout (pharynx) and interacts with the brush 48.

The insert lock 5 is in a loose state.

Base 1 faceplate mounted on the pipe to be welded. An insert 5 with an insert 5 is fastened in the guides of this base.

The retainer bar 6 of the insert 5 is rotated clockwise, the groove of this bar is guided under screw 11. and fixed in this position with this screw. The spring-loaded ball 8 of the retainer of the insert 5 ensures that the latter is pressed against the guide base 1.

Then the electrode 22 of the burner is installed on the butt of the pipes to be welded with the required clearance, fixed by screw 21 and, rotating the screw 50, with clamp 4 presses the insert 5, thus fixing the faceplate on the pipe to be welded.

0 Thereafter, a second half ring consisting of a helical half ring 12 and a half ring 17 of the burner is installed in the sliding bearing of the base 1, and the half rings are connected by hooks 29, ensuring reliable contact of the half rings 17 and 18 of the burner.

In the channel 34 serves coolant through the tube 35 and rinsed with inert gas channels 3 and 14.

0 The air gap between the end of the electrode of the 22 torch and the welded joint pierces the oscillator, ignites the arc. The welding current from the current lead 49 feeds the brush 48 through

5 which goes on half rings 17 and 18.

A worm wheel, consisting of half-rings 12 and 13, gets rotated through a worm to 45 of drive 2. Brush 48 slides over half-rings 17 and 18,

0. Which rotate together with half rings 12 and 13 of the worm gear. Thus the pipe welding process begins.

A shielding gas, such as argon, is supplied through channel 3 of base 1

5 into the channel 14 of the worm gear and then through the opening 26 of the half ring 12 into the chamber 27 of the half ring 17. In addition, through the opening 16 of the base 1 and the plate 31 of this base, the protective gas enters the cavity of the channel 15 and fills it. The protective gas pressure, which is located in the cavities of the channels 14 and 15, acts on the antennae 33 of the gasket 32,

5 located along the edges of the channels, thu | contributes to their preload to the plate 31.

Claims (3)

This ensures reliable sealing of the channel 14 and eliminates air leaks in the exit zone of the channel Z.Esli. a slight leakage into the channel 14 will occur, then shielding gas will be sucked from the channel 15. S Coolant, flowing through the tube 35 into the channel 34, provides maximum heat removal from the bottom of the 1 faceplate, which is heated from the welding arc through the welded pipes. The intensity of heat traps is due to the intensity of mixing of the coolant in channel 3 due to the presence of a spring 37 with a square cross section and different pitch of turns on larger and smaller diameters (tt), which contributes to an increase in the quality of welding, as the heat sink stabilizes the temperature of the faceplate, prevents it from excessive overheating, maintains the channel tightness and ensures the normal rotation of the worm wheel. In addition, the intensity of the heat of the water of the cooling tube in the channel 3 increases due to chi at the end of the tube 35 of the spring 1 with a square cross section and the direction of the turns opposite to the direction of the turns of the spring 37 located in the channel 3 and due to the location of the outlet. the tube 35 and the inlet of the tube 36 at an acute angle to the channel Z, since this promotes even more mixing of the liquid in the channel 3, increases the flow turbulence. The cooling fluid passing through the end of the tube 35, under the action of the spring 41, twists its flow in the direction opposite to the direction of the flow in the channel 3 under the action of the spring 37, and enters the end of this channel because of the location to the latter at an acute angle i. Starting movement along channel 3, the fluid flow is forced to twist under the action of the spring 37 in the direction opposite to the swirling flow at the outlet of tube 35 and, having reached the end of the exhaust channel of channel 3, the flow is once again forced to move in the opposite direction. Since, the ST tube is also located at an acute angle of C to this channel. The lids 2 provide better protection of the weld from oxidation, since they contribute to the formation of a chamber near the seam filled with protective gas, the excess of which goes outside through the gap in the honey with these lids and welds (tube), as well as through the gap between the liners. quality of welded pipes. In addition, through the covers of k2 one can observe the process of welding visually without using safety glasses with light filters, since the covers are made in the form of protective light filters made of quartz glass. In the process of welding, the welding head is removed from the pipeline in the following sequence: one half ring, for example, 12, a worm gear with a half ring, for example, 17, burners disconnect from the other, consisting of half rings 13 and 18, releasing the hooks 23, loosen the screw 11 and the retainer bar 6 of the insert 5 are retracted counterclockwise, loosen the screw 50 of the grip k and remove the insert 5, then remove the head from the welded pipe. At the end of welding, the cooling fluid continues to flow into channel 3, thereby ensuring complete cooling of base 1 before the next pipes start welding. When changing the diameter of the pipes being welded, the nozzle 20 is replaced if it is not designed for welding pipes of this diameter, i.e., if the pipe diameter is not in the range of the diameter of the pipes being welded, for which the nozzle is calculated. In addition, the covers 42 and liners 51 are replaced with new ones corresponding to the diameter of the pipes to be welded. Thus, replacing only the nozzles 20, the cover 42 and the inserts 51, it is possible to weld pipes with diameters of, for example, from 6 to 30 mm, which expands the technological capabilities of the welding head. The use of the proposed head for automatic welding of non-rotating pipe joints in comparison with the known ones allows improving the quality of the pipes being welded due to ensuring reliable supply of protective gas to the welding zone excluding gas losses and air leaks into the gas annular channel of the worm wheel due to the presence of additional annular gas channel and sealing film with antennae at the edges of the main and additional annular channels of the worm gear, as well as due to the presence of protective caps in the burner, forming a chamber near the weld, the volume of which is filled with protective gas, which protects the weld from oxidation and due to the intensive heat removal from the base of the faceplate due to the cooling channel with a spring inside it, which also contributes to the reliability and durability of the welding head; visually observe the welding arc in the process of welding due to the fact that the go covers; reels are made in the form of protective filters made of square glass, which excludes the use of glasses with protective light filters by welders, and this makes the welding head more convenient to operate; increase labor productivity by 20-30 by ensuring fast fixation of the insert in the guide bases, eliminating time for cooling the faceplate and significantly reducing the time for eliminating defects in the weld. Claims of the invention 1. A head for automatic welding of non-rotating pipe joints, comprising a faceplate consisting of a body and a base in which a gas supply duct is made and a catch is placed with an insert and a retainer. a worm gear consisting of two half rings, one of which has a main collector gas channel, a burner containing two half rings, one of which is rigidly connected to the worm wheel half ring with the main gas channel, a tungsten electrode rigidly fixed and a replaceable the nozzle, and the other half ring is rigidly connected to the second half ring of the worm gear, and the drive, kinematically connected to the spinning wheel, is connected to the worm gear, in order to improve the quality of welding and performance.On the side of the outer diameter of the main collector gas channel, there is a complementary collector gas channel and an opening connecting it with the gas supply channel of the faceplate, and the end surfaces of one of the half rings of the worm wheel and the surface of the worm wheel that are in contact with the faceplate are fitted with a sealing gasket from heat-resistant plastic material I with antennae located at the edges of the additional and main gas collector channels. 2. The head of pop.1, characterized by the fact that the faceplate is made with a C-shaped cooling channel and is equipped with tubes for supplying and discharging coolant. 3.Head on PP. 1.2 o tl. In order that, in order to increase the intensity of the heat sink, the cooling channel is equipped with a C-shaped spring with a square section of the turns. ". The head of the PL. 1-3, the pipe for supplying coolant at the outlet is provided with a spring with a square cross section and the direction of the turns opposite to the direction of the turns of the spring of the cooling channel, and is located in the same way as the tube for draining coolant under the sharp angle to the end of the cooling channel. 5.Header on PP. 1-4, which means that the burner is equipped with replaceable lids made in the form of half-rings made of electrically insulating heat-resistant material. 6.Header on PP. 1-5 tons of tactile so that the replaceable covers are made. In the form of protective light filters of quartz glass. 7.Header on PP. 1-6, characterized in that, in order to ensure quick fixation of the insert in the base of the plank, the insert lock is made in the form of a bar and a rack with a spring-loaded ball mounted with the possibility of interaction with an insert made with a bevel for the latter, one the end of the strap is fixed on the base of the faceplate i pivotally, and the other - you; complete with slot for fixing screw. Sources of information taken into account in the examination 1. The author's certificate of the USSR - 315536, cl. At 23 K 31/06, 1970. 2. The author's certificate CtCP 6WJ65, cl. 23 K 31/06, 1976. 3.Catalog Welding equipment. Center for Scientific and Technical Information Search, 1978, about. 27, Welding head GNA-12-30 (prototype). ii7 tS thirty ffltfg.l & g. & & -b / J 39 DZ J4 37 0 / Fug. 7 r-r