DE1097391B - Process and device for the continuous production of tubular and open profiles that are joined together from several partial profiles and welded longitudinally - Google Patents

Description

GERMAN

It is a method for producing an open profile assembled from several partial profiles known, in which the individual partial profiles progressively with open sides pointing in the same direction side by side in a single rolling mill made of strip-shaped material and then formed under Twisting a part of them together around the longitudinal axis to the overall profile and connected will. This known method was used to manufacture current-carrying guardrails for trolleybuses suggested. The partial profiles consist of different materials, namely sheet metal and with insulating material wrapped copper foils; they are connected by bending and flanging.

In contrast, the invention relates to the production of tubular and open profiles, in particular of pipes, with two or more sheet metal strips formed into partial or preliminary profiles and these preliminary profiles are then welded together to form the desired profile shape. In pipe production, for example, two semicircular cross-sections are initially maintained Manufacture channel profiles, bring them together and then connect them by means of resistance welding. The two semicircular profiles are welded together in such a way that the two weld seams lie vertically on top of each other. In order to be able to work continuously here, you had to have a special one Use the vertical wave rolling mill to shape each of the two strips into a pre-section and synchronize them. Separate tool sets (forming rollers, Electrode rollers, etc.) required. With a program change, therefore, considerable conversion times are required to spend two rolling mills for changing the tools, so that the production of smaller men- ' gen uneconomical and the degree of utilization of such a system is low.

The invention is based on the object of a continuous production of profiles, in particular Pipes or hollow profiles, in which the specified deficiencies are avoided, d. H. the investment costs and conversion times are reduced and downtimes are avoided as far as possible.

According to the invention, this is achieved by using the method described at the beginning in connection with the production of trolleybus wires for the continuous production of profiles assembled from several partial profiles, in which the individual partial profiles with open sides pointing in the same direction progressively next to one another and therefore using a single one Rolling mill formed from strip and then twisting part of them around the longitudinal axis to form the overall profile - method and device
for continuous production
of tubular and open,
from several partial profiles joined together and longitudinally welded
Profiles

Applicant:
Alfred Wögerbauer, Linz (Austria)

Representative: Dipl.-Ing. W. Meissner, Berlin-Grunewald, and Dipl.-Ing. H. Tischer, Munich 2, Tal 71,

Patent attorneys

Claimed priority:
Austria from April 5, 1957

Alfred Wögerbauer, Linz (Austria),
has been named as the inventor

be guided and connected. By applying this known procedure, the Production of the seam-welded profiles in question here, e.g. B. Pipes, achieved that one with a a single rolling mill and thus achieves lower plant costs and conversion times. Different of the known procedure, it is necessary in the case of the invention after the shaping of the partial profiles to twist at least one of them in a position in which the free edges of all partial profiles for the formation of the hollow profile and for the subsequent stamping welding of the edges directly face.

In contrast to the previously usual procedure in the manufacture of pipes, all of them are used Partial or preliminary profiles, which together produce the desired profile after welding, on the same Forming line or rolling line formed. Compared to the previous way of working, in each frame of the rolling line two punch and two die rollers arranged so that one with half Number of scaffolds. Only at the end of the forming or rolling section are the parallel in partial or preliminary profiles running next to each other on the same level or at least one of them so opposite

009 699/191

twisted together so that the edges to be welded are brought together. To do this if necessary To keep the stresses occurring low, the device for twisting is not immediate arranged behind the forming devices of the preliminary profiles, but with a reasonable distance between them intended.

The invention can be used with advantage for the production of hollow profiles, such as round tubes, rectangular tubes, Triangular tubes, hexagonal tubes or the like, or for the production of open profiles, e.g. B. cross profiles used will. In the manufacture of round tubes and rectangular tubes, both of the Channel-shaped or angular partial or preliminary profiles, one clockwise and the other others counterclockwise, twisted; However, it is also possible to twist only one of the partial profiles in order to scratch the position in which the parts to be welded are located Edges are directly opposite each other. The edges to be welded do not have to be End edges of the part or. Be preliminary profiles. In the production of cross profiles from angular pre-profiles one can proceed according to the invention in such a way that the edges formed by the bend are removed Merges back to back and connects by means of a weld seam.

One of the most important and preferred areas of application of the invention is the production of round tubes with any diameter that can be selected from strips that are formed into channel-shaped pre-profiles. In this embodiment of the invention, the strips are given a shape which, in cross section, consists of two quarter-circle arcs each with a flat piece of selectable length in between. At the end of the forming section, these pre-profiles are twisted by 90 ° from their position plane to one another so that their edges are opposite one another, and are connected by two welds to form a flat oval tube; then the flat oval tube is formed into a round tube, as is basically known per se. With the invention, all pipe cross-sections can be produced with the same shaped parts with a quarter-circle cross-section by only exchanging the flat piece between these two quarter-circle shaped parts, which is possible with very little effort and expense. The tubes with the smallest diameter that can be produced in this way are obtained if the flat intermediate piece is completely omitted; the diameter of such a pipe is 2r, if r is the radius of the quarter-circular shaped pieces in cross-section. The tubes with the largest diameter are obtained by inserting the longest flat intermediate pieces that still find space on the shaft between the two shaped pieces with a quarter-circle cross-section. If / is the length of the flat spacers and r is the radius of the quarter-circle shaped parts, is the diameter of the part to be made

9 7

Pipe 2r + -.
π

This procedure is basically already known in the case of pipes with a weld seam. An in the cross-section width constantly constant, flat-oval-shaped preliminary profile, in which only the flat Areas of the cross-sectional length corresponding to the respective desired diameter of the round tube can be varied, while the round on one side and rounding in on the other connecting sections of the flat parts that go over flat areas and thus the area around the seam always keep the same shape. In this respect, the subject of the invention differs from the perfect symmetrically flat-oval shaped cross-section of the preliminary profile - in contrast to the known case, which is two-part, which causes a more stable position of the edges to be connected during the welding process than with the known flat oval-shaped preliminary profile is the case, which is flat in the slot edge area.

ίο The forming of a · when using flat " Intermediate pieces produced flat oval tube to a round tube can in a known manner behind the Welding machine by means of a forming device, for example by means of a multi-roll sizing machine, be performed. You can do this for a round tube at any time make. In some cases it is more advantageous to stack or ship the flat oval tubes as such, because they take up less space in this state, and the forming to the round tube only before final use, e.g. B. at the construction site.

The process described for the production of round tubes is also without significant changes Can be used for rectangular tubes, hexagonal tubes and similar cross-sections. In the manufacture of rectangular tubes can be U-shaped pre-profiles for rectangles of different cross-sections with the same Tools, e.g. B. forming rollers, if their distances on the shafts of the molding machines adjusted accordingly. Cylindrical intermediate rollers can be arranged between the forming rollers will. To apply such intermediate roles on the shafts must generally The outer stands of the form rolling machines and all of the upstream rollers must be removed. To avoid this, sees a special embodiment of the invention, which is described in more detail below, in two parts Intermediate roles. These sit z. B. with a cone between the actual forming rollers and are held by them. When converting to a different size, the outer stand of the Form rolling machine stop. It just needs the tool attachment loosened and tightened again will.

If square tubes or tubes with an approximately square cross-section are to be produced according to the invention, these can be viewed as rectangles and produced according to the procedure already given. Another embodiment of the invention provides square tubes by welding two together Manufacture angle profiles. Here, two angles formed next to each other are set at 90 ° against each other twisted, brought together with the free edges and then welded the edges together. With This process can be used to manufacture square tubes of various dimensions without substantial Changes to the tools, e.g. B. pre-profile forming rolls must be made. After this The square tubes can be welded using calibration tools (drawing dies, forming rollers) that are used during the program change only require a job, but not a tool change, to tight dimensional tolerances to be brought. So all square tubes that fall within the dimension range of the system can be can be made with a universal tool kit. With relatively sharp-edged square tubes (corner radius less than twice the wall thickness), the invention provides that the angular pre-profiles only by chamfering the edges (rolling or planing) for

Weld to be prepared. When producing square tubes with more rounded edges you can, however, proceed in such a way that initially the edges of the flat starting strip are rotated by about 45 ° bent and then the angles are formed. While in the first case two angle seams the Connect pre-profiles to a square tube, in the second case it is a connection by means of Butt sutures.

Another embodiment of the invention provides for the manufacture of triangular tubes from three strips. In this embodiment, the edges of three strips are bent up by about 60 °. During the median runs untwisted through the system, the two outer strips are twisted to each other by 120 °, so that two pre-profile edges face each other. The weld is called a resistance weld executed, either three welding transformers, each from one phase of a three-phase network be fed, provided, or there can be three welds in parallel on the same AC phase must be connected.

The welding can be carried out by any method. As particularly suitable The conductive and inductive variants of the electric notch-effect welding have proven themselves. procedure of this type are known. Any metallic materials, such as unalloyed and alloyed steels, chrome steels, aluminum and magnesium alloys, titanium, copper among others, be welded.

According to a particular embodiment of the invention, provision is made that the various Weld seams that are laid to form the desired profile are equivalent to one another. According to the invention, the electrode rollers can be used for this purpose in the conductive notch effect welding be pivotably arranged. Is z. If, for example, the upper seam is cooler than the lower, the electrode rollers will be pivoted so that their distance is reduced on the upper side. This will decrease the electrical resistance of the upper weld (shorter notch); the current and the welding temperature increase. Pivoting can be done by a mechanism (operated by the welder or automatically) take place.

In the drawing, exemplary embodiments for carrying out the invention are explained in more detail.

Fig. 1 shows a schematic representation of an overall system in elevation and

Fig. 2 in plan, which is used for the production of round tubes;

Fig. 3 shows ten cross sections I to X of the strips, the pre-profiles and the pipe and explains progressively the individual characteristic stages of the manufacturing process;

FIG. 4 gives, in a manner similar to FIG. 3, seven cross-sections of strips, pre-profiles and one Rectangular tube again, showing the characteristic stages of the manufacture of such a rectangular tube describe;

Fig. 5 shows seven cross sections in the production of a square tube according to the same scheme as Fig. 4;

6 shows a detail of the welding of angular pre-profiles to form a square tube;

7 shows a detail after such angular pre-profiles have been welded to form a square tube ; Fig. 8 illustrates seven cross-sections of the manufacture of a square tube according to another embodiment of the invention;

Fig. 9 shows six cross-sections in the production of a triangular tube, the characteristic production stages comply with the procedure;

Fig. 10 also shows six characteristic cross-sections in the manufacture of a triangular tube another embodiment of the method;

11 illustrates six characteristic cross-sections in the production of an open profile two strips;

12 is a schematic vertical section through a forming device along the line XII-XII of Fig. 2;

Fig. 13 shows a split intermediate roller in elevation and in section;

14 is a schematic vertical section through the welding device, approximately along the line XIV-XIV of Fig. 2; in

15 and 16 is a schematic representation of the principle of welding processes that are preferably to be used explained.

In the example according to FIGS. 1 and 2, two strips of sheet steel, which are as long as possible and which are coiled into coils 1 and 2, are arranged at the head of the system as starting material for the continuous production of round tubes. With the help of a butt welding device 3, the ends of the used collars are combined in a known manner with the beginnings of the following new collars to form endless bands which, for. B. be fed to the system via a loop (not shown). The intermittently operating drive roller set 4 serves to deflect and form the loop. The roller set 5 redirects the belts and feeds them continuously to the other system. A high-low adjustable double roller 6 can be used to relax the ligaments. If the strip is scaled, i.e. hot-rolled, the scale loosened by the rollers 4, 5 and 6 can be used in a cleaning device 7, for example. B. be cleaned by brushing. In the roller pairs 8/9, 10/11, 12/13 and 14/15 of the forming section, which are arranged one behind the other, the two strips are gradually formed into the half-shells 16 and 17. Instead of the forming rollers, drawing dies or the like could also be used. B. by driving rollers, take precautions.

After passing through the forming devices, the pre-profiles running parallel to each other are each turned by 90 ° twisted. The right preliminary profile 16 is counterclockwise, the left preliminary profile 17 is clockwise rotated and both converging so that the hitherto outer and hitherto face the inner edges of the pre-profiles. Then the simultaneous, progressive welding takes place of the two seams. As mentioned, a number of welding processes are suitable for this purpose. It is possible, with autogenous gas fusion welding, with electric arc welding, with electric resistance welding (Johnston Process) or other welding process to work.

In the illustrated embodiment, the welding takes place with the conductive variant of the electrical Notch effect welding. However, their inductive variant could also be provided. In the 15 and 16 these two variants are explained schematically. The principle is that when conductive or inductive supply of the electrical

Stream in such a way that the stream flows around the notch formed between the parts to be connected must, such a high current concentration occurs that the heating required for melting the metal entry. This type of welding has proven to be special for the method according to the invention shown advantageous.

In the example according to FIGS. 1 and 2, the preliminary profiles are passed through two pairs of rollers 18/19 and 20/21 after being twisted. These are adjustable in the transverse direction, as indicated by the double arrows. The inner rollers 19 and 20 act as expanding rollers and, together with the longitudinally adjustable mandrel 22, press the preliminary profiles 16 and 17 against the welding current rollers 23 and 24. At point 25 , the edges of the preliminary profiles meet and weld. The two welding current rollers receive a high electrical current of low voltage via a power source (not shown), which has to make the detour from one roller to the other via the two points of the pre-profiles to be welded and there, due to the notch effect, causes a high current concentration with corresponding heating. In order to prevent the edges from sliding off one another (offset) and to warm the weld seam, pressure rollers 26 and 27 (FIG. 1) are arranged behind the weld seam tips. Two cutting tools 28 and 29 then remove the outer weld burr. The inside of the weld seams can be machined in a similar way, the arrangement according to the invention offering decisive advantages over the arrangement for single-seam pipes through best accessibility and short lever arms.

The welding device is followed by a device for heat treatment 30 in a manner not belonging to the invention. This can either be a cooling device or a reheating device. It can also be left unused.

The tube leaves the welding device as an upright flat oval tube. In the roller pairs 31/32, 33/34, 35/36 , the flat oval tube is gradually formed into a round tube and calibrated with the aid of the four rollers 37 to 40 lying in one plane.

The shaping of the flat oval tubes into round tubes can also be carried out in a known manner using other methods, such as pulling or expanding. In the case of large distances between the place of manufacture and the place of use it is possible to use the better stacking option and the smaller cargo space of the flat oval tubes and only carry out the forming close to the place of use.

The system shown can be followed in the usual way by a device for cutting to length be.

The individual characteristic stages of the production of round tubes from two according to the invention Flat strips are shown in FIG. 3. This shows in section I (corresponding to section line I-I of Fig. 2) the undeformed flat strips, in the sections // and /// (corresponding to the cutting lines H-II and III-III of Fig. 2) intermediate station of the Preliminary profiles, in section IV (corresponding to section line IV-IV of Fig. 2) the final shape of the preliminary profiles, in section V (corresponding to section line V-V of Fig. 2) the preliminary profiles by 45 ° against each other twisted, in section VI (corresponding to section line VI-VI of FIG. 2) the preliminary profiles by 90 ° each twisted shortly before the weld, in section VII (corresponding to section line VII-VII of FIG. 2) finished-welded pipe in flat oval shape, in sections VIII and IX (according to the section lines VIII-VIII and IX-IX of Fig. 2) Intermediate stages of the forming from the flat oval tube to Round tube and finally the finished round tube in section X (corresponding to section line X-X in FIG. 2). According to the scheme of FIG. 3, FIG. 4 shows the individual characteristic stages in the production of rectangular tubes made of two flat strips, which are initially formed into U-profiles and then progressively twisted by 90 ° and welded.

In the same schematic representation, FIG. 5 shows the production stages of relatively sharp-edged Square tubes made from two flat strips again, the strips being shaped into angular pre-profiles and twisted by 90 ° to each other. When such relatively sharp-edged square tubes are made should, as can be seen from the illustration, an angle weld must be made.

The preparation of the edges of the pre-profiles for this welding can be done by chamfering or scraping at any point in the passage through the forming rollers.

In Fig. 6, two angular pre-profiles beveled at the edges of the legs 41, 42 are shown immediately before the welding. The preliminary profiles initially touch the surfaces formed by the inner bevels. During the welding that now follows, the closely hatched material is melted along the two weld seams and displaced by the application of pressure. According to the invention, the pressure roller downstream of the welding point has the profile 43, so that the welded square tube edges receive the same curves that the unwelded edges 44 and 45 assumed when the preliminary profiles were formed. Fig. 7 shows a square tube with edges welded in this way after passing the pressure roller. The resulting inner burr 46 can either be left or removed.

In the same representation, FIG. 8 shows the characteristic production stages of the production of a Square tube with rounded edges made of two flat strips that are shaped into angular pre-profiles and twisted by 90 ° to each other. In this embodiment, a corresponding Forming the forming rollers, the edges of the preliminary profiles are bent up, so that after the twisting of the pre-profiles, the edges butt meet at 90 °. So there is no bevel here Edges necessary before welding. The tubes made according to this embodiment have stronger rounded edges than those made according to the embodiment of FIGS. 5-7.

9 shows the characteristic stages of manufacture of a triangular tube in a representation similar to earlier with rounded edges made up of three strips. The strips are first passed through the forming device slightly bent up and three shaped preliminary profiles approximately trough-shaped in cross-section. Then the two outer profiles twisted by 120 ° to each other, while the middle profile remains untwisted, and the butt meeting edges connected to each other by three welds.

In the same representation, FIG. 10 shows the characteristic stages of manufacture of a relatively sharp-edged Triangular tube made of three strips again. As can be seen, three angular pre-profiles are first made shaped with an opening angle of 60 ° and

the two outer preliminary profiles are twisted again by 120 ° to each other, while the middle preliminary profile remains untwisted. The butt-meeting edges are welded together. The difference in contrast to the embodiment according to FIG. 9, the weld seams are not at the edges, but approximately in the middle of the surfaces of the triangular tube.

11 shows a further embodiment of the method according to the invention in a similar representation, which can be used to manufacture open profiles. This example uses a cross profile made from two flat strips. The strips are first formed into angular pre-profiles and then twisted by 90 ° so that they come to lie back to back. By means of a Weld these edges are then welded to form a cross profile.

FIG. 12 shows a shaping device which can be used with advantage for the method according to the invention shown, the forming of gutter profiles for the production of round pipes over the intermediate stage of a flat oval tube according to FIG. 3 is used. The device comprises a (not shown) Stand in which the upper shaft 47 and the lower shaft 48 are mounted. With the upper shaft 47 is the Stamp roller set and firmly connected to the lower shaft 48 of the die roller set. The temp el roller set consists of the working disks 49 and 50, the intermediate roller 51 and the spacer rings 52 and 53. The swivel roll set consists of work rolls 54 and 55 and an intermediate roll 56.

As can be seen, the working disks 49 and 50 and the working rollers 54 and 55 cooperating with them have a quarter-circle in cross-section Working surface, so that the strip 58 at the edge parts is a quarter-circle in cross-section Profile is awarded. The cylindrical intermediate rollers 51 and 56 can be exchanged in a manner known per se; their length corresponds to the length of the flat intermediate piece between the quarter-circle Curvatures of the preliminary profile to be produced.

According to a preferred embodiment, the cylindrical intermediate rollers can be known per se Way be made in two parts, as explained in Fig. 13 for the intermediate roller 56 of the die roll set is. The intermediate roller can consist of two half-shells 56 and 56 'which are fastened on the shaft 48 are. Bolts or retaining pins (not shown) can be used as fastening means. very However, the fastening option shown in FIGS. 12 and 13 is advantageous, with the parts 56 and 56 'of the intermediate roller at both ends (57 and 57') beveled in a roof shape and the working rollers 54 and 55 are also correspondingly conical. The conical parts of the work rolls 54 and 55 reach over, as can be seen from Fig. 12, the roof-shaped beveled parts of the intermediate roller and hold the two parts 56 and 56 'on the shaft 48 firmly. This two-part embodiment of the intermediate rollers is when replacing the intermediate rollers, what when changing the diameter of the one to be produced Rohres must be made, of great advantage; because there is nothing more to do than to loosen the attachment of the work rollers 54 and 55 and push them apart, then the two Place the half-shells of the next intermediate roll on the shaft and fasten the parts 54 and 55 to put it back on. However, the work rolls 54 and 55 themselves are never changed, and the parts of the stator in which the shaft 48 is mounted also never need a program change to be removed.

In the same way as the intermediate roller 56 of the die roller set, the cylindrical intermediate roller 51 of the stamp roller set can be made divided, although this is not shown in the drawing is. The stamp rollers 49 and 50 only need to be replaced when the wall thickness of the one to be produced Pipe should be changed. Otherwise, if the pipe diameter is changed, just like In the case of the swivel roll set, only the intermediate roll 51 was replaced. In any case, it should be emphasized that with Use of this device, in contrast to the known devices, only a relatively small inventory of tools is required and the assembly work is reduced to a minimum when changing programs are.

As already briefly mentioned, according to a preferred embodiment of the invention, provision is made, that for the welds that are placed to form the desired profile, a uniform Goodness is guaranteed. Measures are taken to ensure the same welding temperatures. Is z. B. the conductive variant of electric notch welding for the production of round tubes used in accordance with the scheme of FIG. 3, the two welding current rollers are used according to the invention arranged so that the distances to the weld seams can be changed. In Fig. 14 this is explained in more detail using an example. The welding current rolls are in this case about two of the pipe axis Axes that are as close as possible are arranged to be pivotable.

The electrical current is supplied via a transformer with the primary winding 59 from the secondary winding 60 fed to the two carriages 61 and 62. The power roller supports are on the bolts 63 and 64 65 and 66 pivoted. You can have your own organs, e.g. B. the rods 67 and 68, pivoted in this way be that the lower welding current rollers 69 and 70 cover smaller distances to each other than the upper Welding current rollers 71 and 72. The welding current can either be applied to the upper rollers via a second Transformer (not shown) or via the intermediate disks 73 and 74. He is going to the parts near the seam are fed to the preliminary profiles 75 and 76. The top seam turns out to be cooler than that lower, the welding current rollers are to be swiveled towards each other. If the lower one is cooler than the upper one, so are swivel the welding current rollers apart. If both are too cool, the current must be increased. Is the distance the weld seam tip from the welding current rollers too large, then the carriages 61 and 62 and so that the welding current rollers approach each other.

The invention offers a number over the methods and devices in use of advantages. Since the pre-profiles for the tools, e.g. B. forming rollers, are accessible from both sides and can be completely enclosed by the tools, the invention enables a significant greater freedom of movement with regard to the pipe cross-sections. It allows immediate production of shapes that previously had to be produced by a subsequent drawing process. The freedom of movement also affects the relative wall thickness. In addition to the usual pipes, it can be both relatively thin-walled as well as relatively thick-walled are produced. It is also possible to use tubes with beads, Produce grooves or shoulders by welding together correspondingly shaped pre-profiles.

009 699/191

Claims (9)

Patent claims: 1. The application of the process to continuous Manufacture of profiles assembled from several partial profiles, in which the individual Partial profiles with open sides pointing in the same direction progressively next to each other in formed from a single rolling mill from strip and then by twisting part of them around the longitudinal axis are brought together and connected to the overall profile, on the production several shell-like partial profiles composed and longitudinally welded hollow profiles, in particular tubes, with the proviso that after the shaping of the partial profiles at least one of them is twisted into a position in which the free edges of all partial profiles to form of the hollow profile and for the subsequent stamping welding of the edges are directly opposite. 2. The method according to claim 1 for the production of round tubes, in which initially a flat, oval-shaped and seam-welded preliminary profile with one of the diameter of the later pipe independent constant cross-sectional width, but dependent on this cross-sectional length generated and this is then formed into a round tube, for example by drawing, thereby characterized in that two strips are formed into two channel-shaped partial profiles which in cross-section from two quarter-circle arcs each with a flat piece in between, selectable Length exist, and these partial profiles are then twisted to each other by 90 ° from their plane of position are, whereupon the edges are welded together to form a flat oval tube and that Flat oval tube is formed into a round tube. 3. The method according to claim 1 for the production of square tubes, characterized in that the strips formed into angular partial profiles and optionally their edges before Welding beveled or the end parts of the partial profiles to be welded are bent. 4. The method according to claim 1 for the production of triangular tubes, characterized in that three strips formed into angular partial profiles and then the two outer partial profiles are twisted against each other, while the middle part profile remains untwisted, whereupon the edges all partial profiles are welded to form a triangular tube. 5. The method according to claim 1 to 4, characterized in that the welding of the edges the partial profiles in a known manner inductively or conductively using the electrical Notch effect is carried out. 6. Apparatus for performing the method according to claim 1 to 5, characterized by for Forming of the partial profiles known, one behind the other arranged molding devices, in particular Form rolling stands, on whose shafts two or more form rolling tools are arranged next to one another are. 7. Apparatus according to claim 6, characterized in that the form rolling tools, in particular the forming rollers, divided into planes perpendicular to the shaft axis and parallel to the shaft axis Split spacer or intermediate rollers can be adjusted to a selectable profile width. 8. Apparatus according to claim 6 or 7, characterized in that to reduce the torsional stresses a corresponding one between the molding devices and the welding device Distance is provided. 9. Apparatus according to claim 6 to 8 with a conductive welding device, each two Has welding current rollers for producing one weld seam each, characterized in that that the welding rollers are mounted pivotably about axes arranged parallel to the pipe or profile axis are, d. H. the distance between the welding current rollers and the welding seams can be changed. Considered publications: German Patent Nos. 724547, 317 946; German interpretation G9088Ib / 7a (published on November 22, 1956); German patent applications H9195Ib / 7b
made known on November 13, 1952), R7676Ib / 7b
made known on 12th 3.1953); British Patent Nos. 123 052, 695 102; U.S. Patent Nos. 2158 656, 2,502,012,
632. In addition 3 sheets of drawings © 009 699/191 1.