DE1627515C3 - Centering device for welding pipe joints - Google Patents

Description

The invention relates to centering devices for welding pipe joints with an im Tube movable carriage and a three-dimensionally adjustable clamping system, one in the radial plane of the tube arranged, disc-like clamping body and on the inner surfaces of the two Pipe ends to be welded together in the radial direction with hydraulically compressible clamping elements U-shaped, the welding gap overlapping clamping segments

Such centering devices are required when laying pipelines in the field, namely there their job is to center the pipe ends before and during the root weld, so to align the pipe ends exactly. This includes any edge dislocations be evenly distributed over the circumference that the pipe ends may be in a certain Curve shape are brought and that during the laying of the root caterpillar compliance with the for the Welding of the most favorable web spacing is guaranteed. All of these requirements must also apply to pipelines with very large diameters can be taken into account. On the other hand, the devices be designed in such a way that the set-up times are as short as possible, because of this to a large extent the Construction progress depends. Of course, the centering devices mentioned should also be constructive be simple, as light as possible and less prone to failure.

Centering devices are already known

pneumatic or hydraulic power amplification, which meets the requirements for small to medium-sized Pipe diameters meet satisfactorily (German patent 1105 539). But is it for root welding of pipes with diameters of about 700 mm and above, so are the

3 4

The devices required for this are very unwieldy, as knives can be the same size. In this its weight increases approximately with the second power of the narrow area of invariable cross-section near dimensions. In particular, all movement processes and force are prepared for the alignment in the seam plane before the extension. Each clamping segment can therefore have its own kinematics with its drives, which are considerable in the internal clamping system. Due to the fact that these devices can no longer be lifted from this arrangement of the operating areas in the hand. When pulling forward through the zone on the inner pipe circumference of the pipe to be welded constantly, the device rotates height not only the advantage is achieved that the community more or less around the pipe axis and weights the whole device only approximately linearly with it, often also edging something because of the asymmetrical increase in the pipe diameter. It is hereby achieved metric rolling resistances on the inner wall of the rather, that the accuracy of the one-pipe. In order to align the device in the vertical position of the web spacing of the size of the pipe and in the seam plane, a diameter must then be independent. Finally, lifting gear that is suitable for bringing the movable, weight-relieved suspension of the centering device into the correct position enables effortless alignment in the seam. Furthermore, as the pipe diameter increases, it becomes more and more difficult to cut quickly and without additional tools, the edge offset, which can be done with little effort,
sen permissible absolute size is constant, all around in To illustrate the inventive concept

the dimensions required for the welding - an exemplary embodiment is explained below,
same. 20 Fig. 1 shows a longitudinal section of the centering

Since the clamping and centering forces through the device in the pipe axis in different planes, direction are transferred diametrically, it is with The carriage with chassis and wheels was only Pipe diameters over 1000 mm are practically not shown schematically, since it is not the actual one more possible, the required centering accuracy is the subject of the invention.

of ± 0.2mm even with asymmetrical clamping forces. as they occur with non-round pipes, on the service side;

ensure. The reason for this lies in the elastic Fig. 3 shows with a partial cut in the seam

between deformations of the plane that transmits the forces, the side view of a clamping segment for ver-components. illustration of the clamping mechanism;

With regard to this prior art, FIG. 30 is FIG. 4 illustrates the functions of a Invention based on the task of a Zen clamping segment with a feed press and the support traversing device to create that also makes it possible to press on the ring beam;

in the case of very large pipe diameters among all prak- Fig.5 is a cross section through a clamping segment

table starting conditions with tangential rollers and jig presses;
Security the required centering accuracy to 35 F i g. 6 shows a section through a spacer gauge to achieve, that is to say, all those conditions must be met with the press in the seam plane and the replenishments that are the prerequisites for a perfect press from the front side. The clamping mechanism 'is performing the weld form. Nevertheless it should be left out here. _ ->'

this also applies to very large pipe diameters. 7 illustrates pivoting of the cocking voice Centering device light, handy and soft 40 segments and the mode of action of compensating fig be prone to failure. It goes without saying that there was also an even distribution of the edging strives that, despite the large dimensions and zes;

Weights of the pipes and the centering device F i g. 8 and 9 show the formation of tangles

the set-up times are as short as possible. tial roles;

The invention solves the problem posed. In contrast, Fig. 10 shows the basic electrical circuit over the known centering devices of the one Check the web spacing.

The type briefly indicated at the beginning distinguishes the one that the centering device has as a connecting element

According to the invention, the fact that the tensioning element and the load-bearing component embellish the ring-shaped structural body as a ring beam supported by spokes 1 with a continuous U-profile. The ring bellows is formed so that the clamping segments between the 5 ° ken 1 are arranged to be radially movable via spokes 30, which only need to bear the weight of the inner tube wall and this ring beam, which is the centering device, the ring beam being firmly connected to a hub 31,
ken the radial reaction forces when pressing on. The hub rests so that it can be tilted, moved and rotated

takes over, and that one on the carriage by means of a shaft 32, which in all directions around a terminal joint and counteracting 55 fixed terminal joint 33 can swing. Two Tension springs in a central position coaxial to the tube axis ela compression springs 34 exercise a two-table on the ring beam sustained axial straightening force in all directions around the side, which he in his central pivot limited pivotable shaft is provided that seeks to hold the position. For radial alignment in tension springs 35 are used at its free end by means of one of the two axles on the shaft, the upper one rotatable and against bilateral spring force from a 60 tension spring 35 a is strong that their additional tensile force Central position of the axially displaceable hub on which the weight of the entire movable device is attached rigidly attached spokes of the ring beam carries. wearing. The tension springs hang on a firmly mounted

In contrast to the known inner centering frame 36.

Devices are therefore in the invention. During the pulling forward to the next pipe joint

If the device had all the functional elements on the surrounding 65, the ring beam 1 is secured by radial fixing presses 37 catch of the device, namely held between the wall in a concentric position on a of the pipe and the said ring beam, its annular, with the ring beam 1 coaxial construction spacing from the pipe wall for all pipe sections 38 frictionally connected to a chassis 39

5 6

are bound. The piston rod of the fusing press 37 de 2 b. The punch 37 α pressed by the hoist approximately in the center of gravity against an inclined walled pipe joint can then be directed in an oblique or one-sided position with only a small force channel 40 of the ring beam 1, whereby the ring beam application by pivoting and pushing forward will. However, in order to be able to comply with the exact requirements and when the piston is extended further, the optimum web spacing in the seam is first aligned. force, the feed presses 12 are used.

When pushing the newly welded det, which attack in the middle of the segment and the rotatable tube, a conical slide-on frame protects the segment walls 2 b against a return spring 14 'in the ring bar. It consists of sliding rods 42 and handle direction of the fixed segment walls 2 α pivot ring 41, which also serves as a handle for aligning until the pipe ends on the spacer gauges 15 all around the device. The sliding rods 42 are firmly attached. The counterforce of the post stiffeners 43 is attached to the ring beam 1. Extension press 12 over the plate 13 of the two dem can be attached to each clamping segment further deflection tie rods 14 directly and in the shortest possible way with two sliding rods each (not on the fixed wall 2 α and thus placed on the other) . The rotary motion of the ring beam is transmitted around the 15 pipe string. Although in this way each shaft 32 can be actuated by stops to about ± 20 ° of the clamping segment, it will be limited in order to suffice the hydraulic hoses for the many cases when only every second clamping press is to be spared segment the supply press receives, namely

The joint 33 and the frame 36 as well as all, expediently only the clamping segments with the regular equipment, such as the hydraulic pump ao two distance gauges 15. The swivel walls of the unit, all solenoid valves, traction motor, battery, other segments are then pushed by the Rectifiers, etc., are taken along on the chassis 39 of the benden pipe wall.
Trolley mounted, the arrangement being made in such a way that every second clamping segment is spaced two apart so that the overall center of gravity is as low as possible. teach 15 placed near the ends. At the front end of the car is the lance shaft 60. 25 The spacer gauge made of hardened spring band steel of slightly greater length than the one to be welded on is connected by a press that presses radially inwards. At the front he carries the lance 16 over parts 17, 18 and 19 inwards out of the head and guides the power and control cables. The Wa seam joint pulled out, the counterforce on gene is movable by means of wheels 50 inside the welded shortest path over the part 19 α of the Wän pipe string. 30 the 2 α and 2 b is transferred to the pipe ends.

On the pressure-resistant and rigid Ringbai- The tension springs 20 lead the teaching at pressureless kenl, the radially displaceable clamping press are based back in the outermost end position 15a. When segments 2 from, which are each of a hydraulic application of the new pipe joint, all press 3 can be pushed outwards. The teaching in this end position, whereby it has so much over the clamping segment also has a U-shaped transverse 35 the pipe end protruding outwards that the cut, with the two side walls 2 α and 2 δ coming pipe joint when partially extended, so to speak as » inner and outer clamping system «clamping segments cannot run over the gauges, the radial forces on the two pipe ends over- (see Fig. 5). To absorb the inertia forces when wearing. The clamping segment can rotate around the passage of the pipe, the reinforcing strips rotate the axis of the shaft 5, so that the pipe diameters on both sides are stigt even with under 40 21, the pipe diameters differing in full gauge width on the gauges. The gauge with the bar is guided in a clamping force that is equal. The force of the press recess of the boom 22, which also transfers the impacts from the rod head 4 via the shaft 5 and when it hits the pipe end. After the bearing blocks 6 are transferred to the clamping segment 2, the gauges are in the welding position. The clamping segment is guided by the two 45 ISb and withdrawn (FIG. 5). For this purpose, for example, supports 7 next to the press, the pin 5 slides in a manner (not shown) stop on the two longitudinal slots 8 gauges. The two leaf springs in this position are used for the further linkage that holds the guide in the seam direction when the oil pressure is reduced. After the welding is finished, the 9 made of spring band steel, which will slide into the slots 10 in all the gauges with the full force of the press ring beams 1. The leaf springs 9 align the 50 pulled out of the seam and then moved further in segment 2, initially tangentially and axially. Except the inner end position 15c, where the stop before they act to tilt the segment around which was automatically notched.
Axis of rotation 5 opposite. Since this counterforce with the order of the centering device until the application of the

The size of the edge offset increases, the clamping segments are to be held firmly in the aligned position sufficiently centered, especially at the beginning of 55 th, are directed in the radial direction of the tubes, no axial pressure force acts during tensioning, pressure-actuated plungers 23 are provided. As soon as all and therefore the radial friction abut the spacer gauges and the ring beam in the 15 is low. The restoring force of the spring strip is aligned vertically, the support presses Fen the section modulus of the pipe ends 24 of the punch 23 is put under pressure. It is then customized. To the size of the edge offset locally 60 of the ring beam 1 with Aufgleitgestell 41, 42, 43 Kraftzu can limit, in addition to the leaf spring 9, a solid connection with the already laid pipe string ver-stop be attached. tied so that the Aufgleitstoß directly on the

In order to transfer the swiveling and the axial pushing in of the pipe string and to enable the clamping segments of the new pipe to be welded on, be conserved. As soon as the new pipe rests against the Abwenn the pipe ends already clamped and centered 65 and is roughly aligned, the outer wall 2 b of the segment is rotatable and the segments are completely extended to> ollen stored around the axis 11. The pivoting clamping pressure is thus applied, then the punch 23 is automatically withdrawn to the point of the pipe in the plane of the outer wall, and finally the T feed presses 12

7 8

actuated. The support presses 24 are expediently controlled by a solenoid valve each. Since the individually At the level of the middle of the segment on the ring bar, systems are attached under the same oil pressure. hen, despite the separate kinematics, the

For further transfer of the radial clamping both pipe ends apply the same force all around.

Forces on the two pipe ends are used in per se 5 beats, and the ring beam will, even when lapping

known way pressure rollers 25. Those in the same Ab- tubes, circularly symmetrical put under pressure

rollers mounted on the circumference of the segments The total weight of the clamping segments with accessories

enable you to hear tangential movements during clamping and all presses take linear action with the pipe

between segment wall and pipe, which increases the diameter. The weight of the ring beam

edges of the segments with out-of-round tubes or with io changes with a slightly higher power because

asymmetrical starting position of the centering device - whose cross-section is approximately linear with the pipe diameter

tion is avoided. Appropriately, the knife grows. To save weight, you can

Segment four pairs of rollers provided. About these all load-bearing components made of a light metal

According to the invention, rolls are manufactured at the same time as the axia- tion. Denotes η the number of

len transfer forces, for which the rollers 15 clamping segments, then for a device

are specially trained. The two middle numbers required: η clamping jacks 3, η

Rolls 25 α on the swivel wall are given a gerif spacer gauges 15 with presses 16, n / 2 replenishment

felt profile (Fig. 8), all middle rollers 25 b on presses 12, η or n / 2 support presses24, n / 2 fixing

of the fixed segment wall press an edge in the middle of the roll 37, 5 magnetic control valves, plus 1 control

(Fig. 9) and all outer rollers 25c a smooth, 20 reducible reducing valve, 5 hydraulic hoses for

crowned profile (Fig. 5). The profiles of the rollers 25 α carriage, 6 spokes 30 and 6 slide arms 42.

and 25 c are arched according to the swivel radius r Since it is difficult with larger pipe diameters

(Fig. 8), so that when the wall is swiveled, the entire circumference of the seam can be overlooked in order to

Pushing the pipe joint the distance from the infeed, whether the pipe ends on all distance gauges

Pivot axis 11 and thus the clamping pressure are in full contact with each other, the following measuring arrangement is provided.

stay constant. So there will be the supply forces (Fig. 10). At four points on the ring bar 1,

is only transmitted via the inner pairs of rollers, namely right, left, top and bottom, respectively

rend the outer pairs of rollers for something smaller in the vicinity of a gauge checked whether both webs the

Swivel radius can be slid along. Touch teaching and work together sufficiently

In the case of machine welding, the bar is pressed off. For this purpose, a current source 52 is constant over the circular seam expediently lower tension over a relatively high difference set, with the web spacing or stood 53 on the two side walls of the clamping web seam gap laterally by 0.5 to 1 mm larger than with Mentes. The one lying on the side walls 12 o'clock and at 6 o'clock. This is achieved first. Voltage is tapped as close as possible to the pipe fed by different thickness of the spacer gauges at 35 and an amplifier 54. A tilting scarf at the same time Actuation of the axially acting readjustment can then be achieved when the pressure drops below an adjustable push-button. But the pipe ends would have to address a relay in ren value, which is a signal axis Direction are deformed, for which purpose strong additional lamp 55 switches. As long as the relevant teaching additional forces would be required. If not at all with a certain pressure from the two thin-walled pipes is recommended, the 40 pipe ends are actually touched, the tension is between knew elliptical deformation according to the German the two segment walls relatively high. As soon as on Patent 930 701, whose additional power requirement, this point both pipes strong enough against the especially with larger pipe diameters, neglecting is pressed, the voltage tap is casually small. For this purpose, segment walls are practically short-circuited, the voltage at the amplifier is formed, that the two pitch circles of the rollers and 45 ker collapse because of the high resistance the outer edge of the clamping segment walls on one of part 53, and the toggle switch responds. It Lying ellipse. There is then a clamping seg for each quadrant - any other circuit can of course also be used, elements of different shapes, but of the same height, which respond to a change in resistance. and length. Since the absolute deviations of the Elwand are. There are four silipses in the lance head from the circular shape of the change in the bar end lamps 55 in a spatially analogous arrangement, Standes are proportional, i.e. independent of the so that the operator gives the crane driver a Pipe diameter, make a wave of the larger changes in the pipe position Pipe diameters hardly noticeable. can.

The segment presses 3 are operated via a distributor

tube fed in the ring beam 1, are always un- 55 as follows: As soon as when pulling forward within

the same pressure. The feed presses 12 are the device for the welded pipe string

through a hose the length of two pipe ends is approached by hand or automatically

Clamping segments connected to one another. The propulsion motor thus formed is switched to creep speed and

dete ring line is stopped by a longer hose when the ring beam 1 is connected to the

connected to the solenoid valve in the chassis. All ^{6o stand} gauges 15 are located approximately in the weld seam level.

Presses 16 are controlled by a solenoid valve. Then by pressing a button

bar oil pressure actuated. These presses are also at the same time the clamping segments 2 by about 75% and

a ring line is connected, which individually loads the gauges 15 by 100% of their strokes to the outside

Connecting hoses between the clamping segments (Fig. 5) and the fixing presses 37 inserted

ten exists. The support jacks 24 are on a ver ⁶ 5 ren. Now the operator who is on

divider line connected in the ring beam, the Fi- pipe joint is next to the device with the

xierpressen 37 on a distribution line in the ring-shaped grip ring 41 the device in the vertical position,

component 38. These two systems are also used, for example, when observing a built-in water

balance, and presses the device against the pipe end so that all the gauges are in contact and protrude about the same distance to the outside. Now, by pressing another button, the presses 24 are extended until the holding stamps 23 are in contact all around and until the associated distribution line is under full pressure. After the ring beam 1 is in force-fit contact with the welded pipe string, the new pipe is pushed over the slide-on frame up against the gauges, as indicated in FIG. At the same time the new pipe is roughly aligned by the crane operator of the side tree tractor and then from the lance head, which protrudes slightly at the free end of the pipe, the control button of the clamping segments is actuated by a second operator until it is fully extended. The clamping and centering is finished when the distribution line of the presses 3 is under full pressure. A pressure switch then responds, which causes the presses 24 to relax and the spacer gauges to be withdrawn into the welding position 15 b. The feed presses 12 are then operated manually or automatically, whereupon the new pipe joint is drawn in completely and brought to full contact with all the gauges * Here the man on the lance head observes the> four signal lamps. If the end of the pipe is not yet firmly seated on one side, he gives the crane operator a wink until all the lamps light up evenly.

This completes the centering process and the welding of the seam root over the gauge-free Clamping segments can begin. After half of the root layer has been brought in, through

ίο Press the key from the lance head learn the lessons from the Seam drawn inwards into the end position 15 c. Now you can also use the sections that are still open be welded so that an all-round closed seam root is created.

The command to retract the clamping segments simultaneously triggers the retraction of the fixing presses 37 off, so that the entire clamping ring is optionally aligned again perpendicular to the pipe axis and is held securely while pulling forward. As soon as after pulling out the lance head the power cable protrudes from the pipe and is coupled; it will only be back shortly before the next one Prefer removed.

For this purpose 3 sheets of drawings

Claims (8)

Patent claims: 1. Centering device for welding pipe joints with a carriage that can be moved in the pipe and a three-dimensionally adjustable clamping system that has one in the radial plane of the Tube arranged, disc-like clamping body and on the inner surfaces of the two to be welded together Pipe ends in the radial direction hydraulically compressible clamping elements with U-shaped, the welding gap overlapping Has clamping segments, characterized in that the clamping body as of Spokes (30). Ring bar (1) is designed that the clamping segments (2) between the inner pipe wall and this ring beam are mutually radially movable the ring beam takes over the radial reaction forces when pressing, and that an am Carriage (39) by means of a terminal joint (33) and counter-rotating tension springs (35, 35 a) elastically held in the center position coaxial to the pipe axis, in all directions around the Joint (33) limited pivotable shaft (32) is provided, which means at its free end one on the shaft (32) rotatable against spring force (34) on both sides from a central position axially displaceable hub (31) the rigidly attached spokes (30) of the ring beam (1) carries. 2. Centering device according to claim 1, characterized by .ein with the chassis of the movable carriage (39) firmly connected to the Ririgbalken (1) coaxial component (38) with a power source (37) distributed over its circumference. standing, radially against the inner surfaces of the ring beam (1) pressing stamps (37 a). 3. Centering device according to claim 1 or 2, characterized in that the clamping segments each around an axis of a shaft (5), which are in the seam plane _: perpendicular to the direction of the radial clamping force, pivotable and by two each on the ring beam (1) and on leaf springs (9) attached to each clamping segment (2) are held in their central normal position. 4. Centering device according to claim 1, 2 or 3, characterized in that one side wall (2 b) of the U-shaped clamping segments each around an axis (11) in the plane of this side wall parallel to the pivot axis (5) of the entire clamping segment is pivotable by means of a feed press (12) in the direction of the fixed side wall (2 d) , the reaction force being transmitted directly to this fixed side wall by two tie rods (14). 5. Centering device according to one of the preceding claims, in which the side walls of the U-shaped clamping segments for exerting the radial and axial forces on the inner surfaces of the pipe ends are equipped with pressure rollers, the axes of which are parallel to the pipe axis perpendicular to the direction of the radial clamping force, characterized that the running profiles of these pressure rollers (25 d) are curved according to the pivot radius of the side wall in question. 6. Centering device according to one of the preceding claims, with radially outward Distance gauges that can be advanced and retracted inward for setting the web spacing is equipped, characterized in that each spacer gauge has a press (16) directly is assigned, the reaction force on the side walls of the clamping segment in question the pipe ends is transferred. 7. Centering device according to one of the preceding claims, characterized in that that on the side surface of the ring beam (1) facing the previously welded pipe, evenly Distributed over the circumference, several stamps (23) are arranged, which are under the action press from them associated support jacks (24) against the inner wall of this pipe. 8. centering device according to one of claims 1 to 7 with an electrical circuit, those for checking the web spacing at four points on the circumference offset from one another by 90 ° is used, characterized by such a design of the circuit that it is the electrical Resistances between the two pipe ends immediately next to a spacer gauge (15) measures and compares it with a nominal value, the undershooting of the nominal value optically is shown.