EP2866959A1

EP2866959A1 - System for stitch welding in the production of seam heat sealed pipes made of sheet panels

Info

Publication number: EP2866959A1
Application number: EP13734011.3A
Authority: EP
Inventors: Manfred Kolbe; Bernd Kleinjans; Mario THOME; Jochen Vochsen
Original assignee: SMS Meer GmbH
Current assignee: SMS Group GmbH
Priority date: 2012-06-30
Filing date: 2013-06-26
Publication date: 2015-05-06
Also published as: WO2014001408A1

Abstract

The invention relates to a system for stitch welding seam heat sealed pipes (2) made of sheet panels, particularly thick sheet panels, which are shaped to form half-shells (2a, 2b). For each half-shell (2a; 2b) a linear transport path (7) is formed, which paths extend in parallel with, and spaced apart from, each other, and are provided with means for guiding in a supported manner, for pivoting together and for centring the half-shells (2a; 2b) which are pivoted with respect to each other. Two such half-shells (2a, 2b) are connected together by means of stitch welding on the seams thereof resulting from the longitudinal edges lying opposite each other, for which purpose a welding machine (4) is provided.

Description

Attachment for tack welding in the production of longitudinal seam-welded

Tubes made of metal sheets

The invention relates to a system for tack welding in the production of longitudinally welded tubes made of metal sheets, in particular thick metal sheets, wherein in a first step, a metal sheet of a forming machine is fed, in which it is formed into a half-shell and wherein in a second step, two such half shells their seams resulting from the opposing longitudinal edges are stitched together.

Among the methods used in practice for producing tubes from sheet metal is tube forming molding with progressive molding or bending steps on tube forming presses. A pipe-forming or tube bending press usually has in a base frame one of two laterally spaced juxtaposed support or bending bodies existing lower tool and a vertically engageable from above against the lower tool worn by a raised and lowered sword, over the entire length the metal sheet extending upper tool with which a bending force can be applied to the lower tool resting sheet metal.

For the production of a pipe or large pipe according to the progressive molding process several successive steps are required. The metal sheet is usually after the introduction of weld preparations, preferably by means of milling, first pre-bent at the longitudinal edges, usually in a separate edge banding press. The pre-bending of the Longitudinal edges takes place so that the tube radius in the deformation to the slot tube in the region of the later seam, where the longitudinal edges of the bent to the tube sheet metal plate for longitudinal seam welding opposite, is uniformly shaped. The thus pre-bent metal sheet is then inserted into the pipe-forming press and subjected there to the actual bending process. In this case, a bending force is applied to the metal sheet by depressing the press upper part, which sets under the action of the bending load value and carried by this, upper mold a deformation of the metal sheet. This process is repeated several times until the metal sheet has been converted to the slot pipe, the longitudinal seam is then stapled first and then welded in a separate operation to the finished longitudinally welded pipe.

DE 42 15 807 C2 is executed in a frame construction Rohrbiegebzw. Tube forming press has become known and from US 1,952,319 A, the welding of two mutually aligned, on a trolley in a welding system with two welding units for final welding opposite provided welded shells transported is known.

From practice, it is also known to form metal sheets by means of 3-roll bending machines into half-shells and then welded together either manually or by machine. After arranging the half-shells to each other, a stapling seam is usually introduced over the entire length of the resulting tube, by which the half-shells are fixed to each other, wherein the machine welding a first seam from above in a first welding machine and a second seam after a 180 ° rotation is welded in a second machine. The final welding to a tube is then usually carried out in a subsequent step, optionally in another workstation, by introducing a plurality of welds. Manual welding takes a long time and is neither in Cycle time still reproducible in quality. The mechanical welding requires because of the second welding machine including rotating device higher investment costs and is subject to greater susceptibility to errors and errors. In addition, only pipes with smaller diameters and not as thick, thin-walled sheets can be produced, as well as the quantities are limited and no series production is possible. These known methods are therefore not suitable for heavy pipe weights up to, for example, 55 l with a length of 10-14 m and diameters of about 1,500 to 3,000 mm and sheet thicknesses of 20 to 60 mm. Namely, if the two seams of particular large and heavy shells are welded successively and / or in separate units, there is a considerable risk that the first seam in the manipulation or rotation of the half-shells or the pipe is damaged or overloaded and break apart the half-shells or falling.

The invention is therefore an object of the invention to provide a system of the generic type without the disadvantages mentioned, which in particular makes it possible to produce heavy and large diameter pipes by Längsnahtverschweißung with high accuracy, high quality of the welds and reproducible.

The object underlying the invention is achieved with a system of the type mentioned above in that for each half-shell, a linear transport path is formed, which run parallel to each other at a distance, and seen the transport paths in the product running direction with a means for supported guidance, for pivoting together and for centering the mutually pivoted half shells trained multi-functional welding preparation unit with a arranged at the end welding machine for tack welding the half shells adjoins, wherein the welding machine is provided in opposite position, each with a welding unit. It can thus be achieved that two half-shells transported in mutually parallel aligned position in front of the inlet side of the diametrically arranged as in the final welding two welding units having welding machine and there by pivoting with their open longitudinal sides facing each other centered against each other can be positioned, then subsequently both seams the zusammengeschwenkten half shells are simultaneously connected by tack welding. Apart from the fact that a turning of the tube is no longer necessary, the simultaneous tack welding of both seams, the tube is stabilized and prevents overloading of the weld. The tack welded tube can not fall apart, which could not be excluded in a particular heavy, large diameter and wall thickness tube due to the considerable masses. In addition, an automatic production process with reduced machining time and thus high efficiency is achieved for large pipes, which can be a mass production realize. The centering positioning of the half-shells to each other needs to be performed only once, with the half-shells can pivot together vertically or horizontally.

Behind the welding machine, the tack-welded tube can be removed immediately, for example via a subsequent Abführrollgang the welding machine.

According to a preferred embodiment of the invention, the transport path consists of two half-shell Zuführrollgängen and these aligned roller conveyors of the multi-functional welding preparation unit, wherein the Zuführrollgänge and the roller conveyors have driven rollers and are provided over the head of the roller conveyors in a linear distance successive pivoting devices, the one Pivotally mounted support means, in particular swivel shells, have, which the on the Zuführrollgänge a take up and pull together the running half-shells from below the plane of the roller tracks, wherein the pivoted half shells come to rest on support rollers arranged in the free linear distance between the pivot shells, and wherein the pivoted half shells in the region of the two seams pressed both from the inside and from the outside, the pivoted half-shells are assigned leading and mutually centering positioning rollers. The half shells deposited on the support rollers also serving for further advancement are exactly positioned and centered over their entire length by the positioning rollers pressed in from the inside and from the outside with effect, in particular in the area of the seams, which allows a connection with minimal sheet edge offset. The positioning rollers also contribute to the fact that the half-shells take up the desired pipe radius as far as possible before welding.

The longitudinal edges of the half-shells can be positioned directly abutting one another over the entire length or can be specifically positioned with a gap distance from one another and brought together only in the welding machine, wherein the longitudinal edges take a V-shaped course with their apex in the region of the welding point.

The simultaneous welding of the stitching seams can be carried out in the opposite 6 o'clock and 12 o'clock positions or in 3 o'clock and 9 o'clock positions of the seams, whereby the half shells can be welded from the inside or the outside.

It is proposed that the support rollers are not driven and, disposed shifter rt upstream of the inlet side of the multifunction Schweißvorbereitungseinhe ^'which promotes the pivoted together half-shells by welding multifunction preparation unit and this subsequent welding machine. The displacement device, preferably with a toothed rack genantrieb or lumber formed and can be provided on the head side with jaw-like gripper means, which detect the half shells frontally, transported the half shells in the production flow in the longitudinal direction evenly through the welding preparation unit and the welding machine through, without that drives need to be synchronized. The gripper means come here with the feed automatically engaged and solve the return stroke automatically from the pushed, stapled pipe.

According to a further embodiment of the invention, the externally and internally pressed positioning rollers and the rollers of both the Zuführrollgänge and the roller conveyors to adapt to varying dimensions of the half-shells are adjusted. The system can thus be adapted to the desired pipe diameter in a wide range. The plane of the support rollers need not be changed, since the support rollers as well as the roles of Abführrollgangs behind the welding machine on the always constant lower edge of the respective pipe.

According to a preferred embodiment of the invention, the pivoting devices on two pivotable about a common bearing axis carrier arms which are arranged below the pivoting shells, wherein the support arms are acted upon by adjusting cylinders and pivoting indirectly with Schwenkabalen cylinder loading, and is provided that on the support arms first, bearing axes close and a second, bearing axis removed frame is attached, wherein in the frame rests adjustable pressure rollers are provided which press the pivoted half shells in addition to the pressed-outer positioning rollers. When pivoting the support arms, the frame racks come with their pressure rollers automatically at the predetermined location of the action with effect on the half-shells radially from the outside for use. In conjunction with the positioning rollers, a desired distribution over the outer circumference of the half shells can thus be provided. achieve centering and guidance. The frame racks are arranged on the support arms so that all occurring pipe diameters can be detected.

It is proposed that the multi-function welding preparation unit is formed with gap spacers that temporarily dip into the seams of the swung-together half shells. These allow the longitudinal edges of the half-shells to be positioned with a certain gap distance before stapling.

Further features and details of the invention will become apparent from the claims and the following description of an embodiment shown in the drawings. Show it:

Figure 1 is a schematic longitudinal view of a system for tack welding half-shells in the production of longitudinally welded pipes made of metal sheets.

Figure 2 as a detail in an enlarged view of the marked in Figure 1 with l plant section.

Fig. 3 as a detail in an enlarged view of the marked in Figure 1 with lI plant section.

Fig. 4 as a detail in an enlarged view of the marked in Figure 1 with III system section.

Fig. 5 is a section along the line AA of Fig. 1; 6 shows a cross-section of the multi-function preparation unit of FIG. 1 in the region of section II and thus FIG. 3 shows a front view; FIG. and

Fig. 7 as a detail in a simplified representation of a pivoting device for pivoting together fed half shells.

According to FIG. 1, a tack welding machine 1 in the production of longitudinally welded tubes from sheet metal plates has as central component a multi-function welding preparation unit 3 with a welding machine 4 immediately following it in the product running direction PLR. The multi-function welding preparation unit 3 is preceded by a displacement device 5 and, downstream of the pipes 2, which are initially stapled, a discharge roller table 6 is connected downstream. The longitudinally welded pipe is made of two sheet metal plates on a - not shown - forming machine, for. B, a molding press or 3-roll bending machine, preformed half shells 2a, 2b and 2a ', 2a ", 2a"' and 2b ^* . 2b ", 2b" (see Fig. 6).

Below and on both sides of the displacement device 5, a linear transport path 7 is formed for each half-shell 2a or 2b. Each transport path 7 consists of a half-shell feed roller conveyor 7a and a roller conveyor 7b adjoining it in alignment below the multifunctional welding preparation unit 3.

The half-shell feed roller conveyors 7a and the roller conveyors 7b are formed by successive, frame-anchored frame brackets 8a, 8b with driven rollers 10 (see also FIGS. 2 and 3) which can be raised in height via cylinders 9. FIG. 6 indicates that the different diameters of the half-shells 2a to 2a '"or 2b to 2b'" are set differently high. See roles 10 recognize as well as their with respect to the center plane lateral adjustability by actuation of cylinders 11th

The multi-function welding preparation unit 3 is formed with a plurality of spaced successive Schenkvorrichtungen 12. As is apparent from Fig. 7, each pivoting device 12 has two pivotable about a common pivot point 13 support arms 12a, 12b with arranged thereon as a suspension pivot shells 14a, 14b. For common pivoting of the support arms 12a, 12b with the pivoting shells 14a, 14b, the pivoting devices 12 are connected to adjusting means 15 which are movably mounted in bearing axis close to the pivot point 13 on the support arms 12a, 12b fixed frame rests 16a. At the pivotable support arms 12a, 12b, a further frame 16b is fixed away from the pivot point or from the bearing axis 13. The preformed supplied half-shells 2a, 2b fitting in the frame racks 16a, 16b pressure rollers 17 are provided, of which the pressure rollers 17 of the bearing axis removed frame 16b by means of actuating cylinder 18 can be adjusted to the respective pipe diameter, as that of Fig. 6 with there for the different Diameter shown positions can be seen.

The support arms 12a, 12b with the pivoting shells 14a, 14b receive the supplied, preformed half shells 2a, 2b below the roller conveyors 7b and pivot the half shells 2a, 2b together, wherein the half shells 2a, 2b in the exemplary embodiment with their longitudinal edges at the top and bottom and there seams 32a, 32b (see Fig.5) for forming the weld opposite each other. In the pivoted state, the half-shells 2a, 2b are independent of the pipe diameter on non-driven support rollers 19 of the multi-functional Schweißvorberei- processing unit 3, the support surface extends in a constant with the lower edge of the tube level. The multi-function welding preparation unit 3 has an assembled from vertical posts 20 and horizontal longitudinal or transverse beams 21 open housing. Therein, on the one hand, positioning rollers 22 which can be positioned externally in the region of the upper seam 32a and, on the other hand, gap spacers 23 which can be inserted from above and below are inserted into the seams 32a, 32b of the pivoted half shells 2a, 2b (compare FIGS. 3 and 4). In addition to the outer positioning rollers 22, positioning rollers 24a, 24b are provided in the interior of the half-shells 2a, 2b or of the slot tube in the region of the seams, which are arranged to be adjustable in a housing 25. For very large diameters, eg 1,500 to 2,000 mm, a spacer can be integrated to reduce the required Anstellhubes.

The resting on the support rollers 19, zusammengeschwenkten half-shells 2a, 2b are pushed to Heftnahtverschweißung of the purpose of a rack and pinion rack 26 having shifter 5 through the multi-point ns- welding preparation unit 3 and the subsequent welding machine 4. The feed is transmitted via mouth-like gripper means 27 (see Fig. 2), which detect the half-shells 2a, 2b with the forward movement of the front side.

The welding machine 4 (see Fig. 4) is formed on its inlet side with a circumferentially closed roller support frame 28 shown in front view in Fig. 5. This has in a manner analogous to the multi-function welding preparation unit 3, in frame racks 29 by means of adjusting cylinders 30 from the outside against the half shells 2a, 2b engageable Andruckrollen 17 positioning rollers 22. Furthermore, here also positioning rollers 31 a, 31 b provided in the area the upper and lower seams 32a and 32b, respectively, are used by the interior of the half-shells 2a, 2b or of the slot tube. 5 also shows how, by a previously mentioned, integrated spacer 33 in a drawn with solid lines of the half shells 2a, 2b large diameter a correspondingly required, longer Anstellweg without changing the for a small Rohrdurchmesser- half shells 2a " ¹ and 2b '" - designed stroke of the actuating means (cylinder) can be bridged.

Claims

claims

Apparatus for tack welding longitudinally welded pipes (2) of sheet metal plates, in particular thick metal sheets, wherein in a first step a metal sheet is fed to a forming machine in which it is formed into a half shell (2a, 2b) and in a second step two such half shells at their seams (32a, 32b) resulting from the opposing longitudinal edges, are joined together by tack welding, for which purpose a welding machine (4) is provided,

characterized,

a linear transport path (7) is formed for each half-shell (2a; 2b) which runs parallel to one another at a distance from one another, and the transport paths in the product running direction (PLR) have a means for supported guidance, pivoting together and centering of the mutually pivoted one another Half-shells (2a; 2b) formed multi-functional welding preparation unit (3) with a arranged at the end of the welding machine (4), wherein the welding machine (4) in each opposite position each having a welding unit (4a). Plant according to claim 1,

characterized,

in that the transport path (7) consists of two half-shell feed rollers (7a) and roller tracks (7b) of the multifunctional welding preparation unit (3) arranged in alignment therewith, the feed rollers (7a) and the roller conveyors (7b) having driven rollers (10) in that, at the top of the roller tracks (7b), successive pivoting devices (12) are provided at a linear distance, pivoting about a pivot point (13). having movably mounted support means (14a, 14b) which receive the half shells (2a, 2b) entering from the feed rollers (7a) from underneath the plane of the roller conveyors (7b) and swing them together, the pivoted shells (2a, 2b) resting in the Free space between the support means (14a, 14b) arranged support rollers (19) come to store, and that the zusammengeschwenkten half shells (2a, 2b) in the region of the two seams (32a, 32b) pressed both from the inside and from the outside associated pivoting half shells leading and mutually centering positioning rollers (22; 24a, 24b) are assigned.

Plant according to claim 2,

characterized,

in that the support rollers (19) are without drive and a displacing device (5) arranged in front of the inlet side of the multifunction welding preparation unit (3) moves the pivoted half shells (2a, 2b) through the multifunction welding preparation unit (3) and the subsequent welding machine (4). promotes.

Plant according to claim 3,

characterized,

in that the displacing device (5) is designed with a rack and pinion drive (26) and on the head side with jaw-like gripper means (27) which grasp the half-shells (2a; 2b) on the front side.

Plant according to one of claims 1 to 4,

characterized,

in that the positioning rollers (22, 24a, 24b) pressed on from the outside and from the inside, and the rollers (10) of both the feed rollers (7a) and the rollers (7a) Roller tracks (7b) to adapt to varying dimensions of the half-shells (2a, 2b) are adjustable. Installation according to one of claims 1 to 5,

characterized,

in that the pivoting devices (12) have two support arms (12a, 12b) pivotable about a common bearing axis (13), which are arranged below the support means (14a, 14b) of the half-shells (2a, 2b), wherein the support arms (14a, 14b) by actuating means (15) can be acted upon and upon application of the support means (14a, 14b) to pivot indirectly, and in that on the support arms (12a, 12b), a first, Lagerachsennahes and a second, Dachsenachsenfernferntes frame (16a, 16b) is attached, wherein in the frame racks (16a, 16b) engagable pressure rollers (17) are provided which press the pivoted half shells (2a, 2b) in addition to the pressed-on outer positioning rollers (22). Plant according to one of claims 1 to 6,

characterized,

in that the multi-functional welding preparation unit (3) is designed with gap spacers (23) which dip temporarily into the seams (32a, 32b) of the pivoted-together half-shells (2a; 2b).