WO2019074453A2

WO2019074453A2 - Pipe production apparatus

Info

Publication number: WO2019074453A2
Application number: PCT/TR2017/050498
Authority: WO
Inventors: Cevdet UNAN
Original assignee: Unan Cevdet
Priority date: 2017-10-13
Filing date: 2017-10-13
Publication date: 2019-04-18
Also published as: WO2019074453A3

Abstract

The present invention provides an apparatus for manufacturing steel pipes by helically forming an elongated strip of metal. A novel pipe production apparatus is provided for helically forming a metal strip comprising a carriage for carrying a substantially planar metal strip in a feeding direction and a frame arranged adjacent to an end of the carriage supporting a metal curling device for receiving the metal strip, curling the metal strip and advancing the curled metal strip in a production direction that makes an angle with the feeding direction to form a pipe in the production direction. Also, a novel curling device for curling a metal strip and a novel roll for advancing a metal strip is disclosed.

Description

PIPE PRODUCTION APPARATUS

Technical Field of the Invention

The present invention relates to an apparatus for manufacturing metal pipes by helically forming an elongated strip of metal, especially steel.

Background of the Invention

In a pipe production apparatus known from the patent document US3650015A, means are provided for advancing an elongated strip of metal in a planar path along its longitudinal axis for feeding to a device for helically forming the metal at which the strip is curled between three sets of rollers into helical convolutions. The three sets of rollers extend in rows at an angle relative to the longitudinal axis of the incoming strip, the angle being related to the radius of the convolutions and the width of the metal strip such that the trailing edge of a preceding portion of the metal strip converges into contact with the leading edge of the following portion of the metal strip. The peripheries of the rollers of the three sets of roller exert laterally directed forces against the strip surfaces for guiding the strip, and the positioning of the peripheries of the rollers of at least one set is precisely adjustable for guiding the strip such that the desired contact between said trailing and leading edges is effected and maintained.

The known helical pipe making apparatus comprises an elongated carriage supported on ground wheels and a stationary frame adjacent an end of the carriage and supporting a curling device. On the end of the carriage, remote from the curling device, is a coil handling means for a strip of metal material in coiled form. Adjacent coil handling means, there is preferably provided a strip separating or peeling means, and at successive stations along carriage there is provided a plurality of strip drive rolls that push the metal strip towards the three set of rollers of the curling device. On the frame, which supports the curling device, there is also a welding station at which the opposite edges of the curled metal strip are joined for completion of the pipe.

Located beyond the leading stand of the drive rolls and projecting from the end of the carriage and to the frame, are a pair of elongated edge guides extending in the direction of advance of strip for guiding the metal strip therebetween, and including an upper flange portion and lower flange portion between which the edge portion of the metal strip is confined for preventing the metal strip from being curved substantially from the generally planar form. The known curling device comprises an assembly of three parallel forming rolls including, in the order in which they contact the advancing strip, a lead roll, a mandrel roll, which is disposed internally of the path of the curled strip, and a buttress roll. The lead roll and the mandrel roll are mounted so that opposite surfaces of incoming strip are engaged thereby, and the buttress roll is supported on the opposite side of mandrel roll from the lead roll, remote from the carriage, and is offset upwardly from the feed path and is adapted to engage the same surface of strip as the lead roll. The lead roll, the mandrel roll and the buttress roll function to curl the strip into an arc with mandrel roll serving as a fulcrum as strip is driven therethrough by drive rolls. Pipes of limited size are produced in known pipe forming apparatus for pipeline projects and then transported to the site of pipeline construction. In order to overcome the limitation due to transportation, the pipe forming apparatus may be installed at the construction site. However, known pipe forming apparatus are too heavy to transport to remote sites and they consume high energy that is difficult to meet in remote sites. Accordingly, an object of the present invention is to provide a mobile pipe forming device, which may be transported to a construction site.

Summary of the Invention

In order to overcome the above mentioned drawbacks of known devices, the present invention provides a pipe production apparatus for helically forming a metal strip, especially steel strip, which is lighter and which consumes less energy.

Present invention provides a pipe production apparatus for helically forming a metal strip comprising a carriage for carrying a substantially planar metal strip in a feeding direction and a frame arranged adjacent to an end of the carriage supporting a metal curling device for receiving the metal strip, curling the metal strip and advancing the curled metal strip in a production direction that makes an angle with the feeding direction to form a pipe in the production direction, wherein the metal curling device comprises drive means to advance the metal strip in the feeding direction. The drive means is configured to pull the metal strip from the carriage, when the metal strip is placed on the carriage in use. Therefore, the drive means, preferably being an electric motor, drive at least a driven roller rollingly engaging the metal strip. Preferably, the production direction makes an oblique angle with the feeding direction. Hence, the longitudinal axis of the carriage may be arranged obliquely to the longitudinal axis of the frame. According to the invention, the frame may be a longitudinal stationary frame and the carriage may be a movable longitudinal carriage supported on ground wheels, such that the angle between the production direction and the feeding direction may be changed to form helical convolutions of metal strip according to the size of pipe being manufactured.

According to the invention, the metal curling device comprises a plurality of rolls, between which the metal strip is to be passed to be curled helically to form a pipe extending in the production direction. Hence, the pipe production apparatus of the present invention provides the technical effect that, during forming of the metal strip to a pipe, the metal strip is pulled by the curling device from the carriage. Namely, instead of pushing the metal strip from the carriage towards the pipe curling device, the metal strip is driven directly by the curling device. Thereby, a lighter and compacter carriage may be employed that is less energy consuming and easier to transport to a remote site for pipe production.

The frame may further comprise a welding station at the second end portion in order to attach the corresponding edges of the curled strip by welding to form a pipe.

Present invention provides a metal curling device for helically forming a metal strip comprising a lead roll for receiving the metal strip thereon, an upper roll, which is disposed internally of the path of the curled strip, a lower roll which is disposed externally of the path of the curled strip, such that the metal strip is passed between the upper roll and the lower roll and a buttress roll on the opposite side of the upper roll and the lower roll from the lead roll engaging the same surface of strip as the lead roll, wherein drive means is arranged to drive the at least one of the upper roll and the lower roll to advance the metal strip from the lead roll between the upper roll and the lower roll and toward the buttress roll. Therefore, the at least one of the upper roll and the lower roll may comprise drive means to advance the metal strip.

Hence, providing a drive means between the lead roll and the buttress roll results in a configuration without the drive rolls and the pair of elongated edge guides before the lead roll, which provides a significant weight reduction and a higher efficiency enabling the pipe curling apparatus to be operated at remote construction sites. The pair of elongated edge guides preventing the strip from curving can be omitted, because there is no drive rolls pushing the strip towards the metal curling device, since the driving means that pull the strip from the carriage is arranged directly at the metal curling device.

According to the invention, at least the upper roll may comprise the drive means, preferably the upper roll and the lower roll may both comprise drive means to drive the metal strip. The lower roll may be arranged below the upper roll, preferably at a variable distance for adapting the pressure for driving the metal strip. The upper roll and/or the lower roll may be vertically adjustable by any suitable means for effecting proper spacing between the upper and lower rolls corresponding to the thickness of the metal strip to be passed therebetween for being advanced by the upper roll and/or the lower roll toward the buttress roll. According to the invention, the metal strip may be received on the lead roll substantially horizontally.

According to the invention, the lead roll, the upper roll, the lower roll and the buttress roll are constructed of a plurality of individual rollers, preferably arranged with their rolling axis substantially perpendicular to a feed path of metal strip or to the longitudinal axis of the metal strip. The lead roll may alternatively be made of a single cylindrical roller, preferably arranged with its rolling axis substantially perpendicular to the feed path of the metal strip or to the longitudinal axis of the metal strip. Individual rollers of each roll are arranged adjacent to each other in a direction at a substantially oblique angle to the feed path of strip and/or parallel to the path of the curled strip such that the strip is curled by the rolls into helical convolutions, wherein the adjacent rollers are arranged shifted and/or offset on the feed path. Hence, rollers of each roll may be arranged in rows with parallel rolling axes to form rollers. Accordingly, the rollers may be arranged pivotally with respect to the frame and/or curling device in order to change the angle of their axes of rotation relative to the feed path of the strip. According to the invention, the upper roll and/or the lower roll may comprise at least a driven roller that is driven by the drive means.

According to the invention, the curling device comprises a beam supporting the upper roll at a first end portion of the frame from which the curled metal strip extends in the production direction towards a second end portion of the frame opposite to first end portion. The beam may be arranged vertically movable with respect to the frame to adjust the distance between the upper roll and the lower roll according to the thickness of the metal strip. The beam may be supported by a substantially vertical column arranged at the first end portion of the frame. According to the invention, the frame comprises a table supporting the lower roll below the upper roll. The table may be arranged vertically movable with respect to the frame to adjust the distance between the upper roll and the lower roll. The upper roll and/or the lower roll are resizable to adapt to the size of the metal strip. The beam and the table are sized and arranged such that the number of the upper and lower driven rollers may be changed according to the size of the metal strip. Therefore, the upper and lower driven rollers may be removably and/or repositionably mounted on the beam and the table.

According to the invention, the drive means is an electric motor driving at least one of the driven rollers of the upper roll and/or the lower roll to pull the metal strip between the upper roll and the lower roll from the lead roll and to push the metal strip toward the buttress roll. Preferably, each driven roller of the upper roll and/or the lower roll comprises a respective electric motor as drive means.

According to the invention, the electric motor may be arranged to drive the driven roller via a transmission, preferably via a planetary gearing. The transmission may be arranged at least partially inside the driven roller. The driven roller may comprise a housing to support the driven roller and the transmission, wherein the electric motor may be mounted at the housing to drive the driven roller. The housing is arranged to be supported at the beam and/or the table on the frame. The housing may comprise side flanges at which part of the transmission is arranged. The driven roller may be arranged to roll between the side flanges, whereby its axis of rotation being supported at the side flanges. The driven roller may comprise internal teeth arranged on its inner surface to carry planet gears. Preferably, the planetary gearing is arranged completely inside the driven roller. The electric motor may be arranged with its axis of rotation perpendicular to the axis of rotation of the driven roller, wherein the transmission comprises a worm wheel driven by the electric motor. Hence, the transmission may comprise a worm wheel at a first driven end and/or a planetary gearing at a second driving end. In order to provide a well balanced transmission, both side flanges comprise part of the transmission to drivingly support the driven roller. The housing may comprise a cover connecting the flanges at which the electric motor is supported between the flanges to keep the housing as compact as possible. Accordingly, the electric motor may be arranged at a radial side of the driven roller. Further, the housing may comprise, preferably on the cover, pivoting means to rotatably support the driven roller at the beam and/or the table on the frame.

The present invention further provides a drive roll for a pipe production apparatus comprising at least a driven roller to advance a metal strip on a feed path in a feeding direction by engaging the metal strip on a substantially planar surface thereof comprising a drive means to drive the driven roller, wherein the drive means is arranged on the feed path. Accordingly, the drive means is arranged on the feed path above and/or below the metal strip to be advanced. Preferably, the drive roll comprises a plurality of driven roller arranged adjacent to each other with their axis of rotation parallel to each other and offset and/or shifted in the feeding direction. The present invention also provides a pipe production apparatus comprising such a roll arranged at a curling device, a frame and/or a carriage thereof to advance a metal strip.

Other objects and advantages of the invention will become apparent from the following description of preferred embodiment of the invention. These and further advantages of the current invention are disclosed in the appended claims.

Description of the Drawings

The above disclosed and further features of the current invention will be better understood with the following detailed description and drawings of the preferred embodiments of the invention. Figure 1 shows a schematically presented top plan view of a preferred embodiment of pipe production apparatus according to the present invention;

Figure 2 shows a top plan view of a preferred embodiment of curling device according to the present invention;

Figure 3A shows a side view of the preferred embodiment of curling device of the present invention in the direction of section A- A on Figure 2;

Figure 3B shows a side view of the preferred embodiment of Figure 2;

Figure 4 shows a preferred embodiment of a driven roller according to the present invention;

Description of Preferred Embodiments

The preferred embodiment of the current invention will be described with references to the appended drawings.

Figure 1 shows an exemplary scheme of a preferred embodiment of the pipe curling apparatus 1 according to the present invention. The pipe production apparatus 1 comprises a carriage 2 for carrying a substantially planar metal strip 3 in a feeding direction F and a frame 4 arranged adjacent to an end of the carriage 2 supporting a metal curling device 5 for receiving the metal strip 3, curling the metal strip 3 and advancing the curled metal strip 3 in a production direction P that makes an angle a with the feeding direction F to form a pipe 6 having a diameter D in the production direction P. The metal strip 3 may be unrolled from a coil 7 arranged at the other end of the carriage 2 opposite to the end adjacent to the frame 4.

The metal curling device 5 comprises a lead roll 120 for receiving the metal strip 3 thereon, an upper roll 100, which is disposed internally of the path of the curled metal strip 3, a lower roll 110 which is disposed externally of the path of the curled metal strip 3, such that the metal strip 3 is passed between the upper roll 100 and the lower roll 110 and a buttress roll 130 on the opposite side of the upper roll 100 and the lower roll 110 from the lead roll 120 engaging the same surface of the metal strip 3 as the lead roll 120. Drive means 8 are arranged to drive the upper roll 100 and the lower roll 110 to advance the metal strip 3 from the lead roll 120 between the upper roll 100 and the lower roll 110 and toward the buttress roll 130.

The metal curling device 5 comprises drive means 8 to advance the metal strip 3 in the feeding direction F. The drive means 8 is configured to pull the metal strip 3 from the carriage, when the metal strip 3 is placed on the carriage 2 in use. Therefore, the drive means 8 according to the present embodiment drive a plurality of upper and corresponding lower driven roller 10, 11 of the upper roll 100 and the lower roll 110 rollingly engaging the metal strip 3. The metal strip 3 is fed between upper and lower driven roller 10, 11 in the feeding direction F.

According to the present embodiment, the frame 4 is stationary and the carriage 2 is movable on ground wheels 9, such that the angle a between the production direction P and the feeding direction F may be changed to form helical convolutions of the metal strip 3 according to the diameter D of pipe 6 to be manufactured in the production direction P by pivoting the carriage 2 about its end adjacent the frame 4.

According to the present embodiment, the metal curling device 5 comprises two upper driven rollers 10 to rollingly engage a top substantially planar surface of the metal strip 3 from above and two corresponding lower driven rollers 11 to rollingly engage a bottom substantially planar surface of the metal strip 3 from below such that the metal strip 3 is compressed between both driven roller pairs 10, 11. During forming of the metal strip 3 to a pipe 6, the metal strip 3 is pulled by the metal curling device 5 from the carriage 2. The number of the upper and lower driven roller 10, 11 may be changed depending on the size of metal strip 3.

According to the present embodiment, the lead roll 120 comprises lead rollers 12 for receiving the metal strip 3 thereon, upper driven rollers 10, which are disposed internally of the path of the curled metal strip 3, lower driven rollers 11, which are disposed externally of the path of the curled metal strip 3, such that the metal strip 3 is passed between the upper driven rollers

10 and the lower driven rollers 11 and buttress rollers 13 on the opposite side of the upper driven rollers 10 and the lower driven rollers 11 from the lead rollers 12 engaging the same surface of metal strip as the lead rollers 12. The drive means 8 is arranged to drive the upper rollers and the lower rollers to advance the metal strip 3 from the lead rollers 12 between the upper rollers 10 and the lower rollers 11 and toward the buttress rollers 13.

The lower driven rollers 11 are arranged below the corresponding upper driven rollers 10 at a variable distance for adapting the pressure for advancing the metal strip 3. Individual rollers 10, 11, 12, 13 are arranged with their rolling axes substantially perpendicular to the feed path of the metal strip 3. The lead rollers 12 may alternatively be made as a single cylindrical roller 12, preferably arranged with its rolling axis substantially perpendicular to the feed path of the metal strip 3. Individual rollers 10, 11, 12, 13 are arranged adjacent to each other in a direction at a substantially oblique angle to the feed path of the metal strip 3 such that the metal strip 3 is curled by the rollers 10, 11, 12, 13 into helical convolutions, wherein the adjacent rollers 10, 11, 12, 13 are arranged shifted and offset on the feed path. The rollers 10, 11, 12, 13 are arranged in rows with parallel rolling axes to form rollers. Accordingly, the rollers 10, 11, 12, 13 are arranged pivotally with respect to the frame 4 in order to change the angle of their axes of rotation relative to the feed path of the metal strip 3.

The curling device comprises a beam 14 supporting the upper rollers 10 at a first end portion of the frame 4 from which the curled metal strip 3 extends in the production direction P towards a second end portion of the frame 4 opposite to first end portion. The beam 14 is arranged vertically movable with respect to the frame 4 to adjust the distance between the upper rollers 10 and the lower rollers 11 according to the thickness t of the metal strip 3. The beam 14 is supported by a substantially vertical column 15 arranged at the first end portion of the frame 4. The frame 4 comprises a table 16 supporting the lower rollers 11 below the upper rollers 10. The table 16 is optionally arranged vertically movable with respect to the frame 4 to adjust the distance between the upper rollers 10 and the lower rollers 11. The beam 14 and the table are sized and arranged such that the number of the upper and lower driven rollers 10,

11 may be changed according to the size of the metal strip 3. The drive means comprises respective electric motors 17 driving the upper and lower driven rollers 10, 11. The frame 4 comprises a welding station 18 at the second end portion in order to attach the corresponding edges of the curled metal strip 3 by welding to form the pipe 6.

Figure 2 shows a top view of a preferred embodiment of the metal curling device 5 according to the present invention having two upper rollers 10 and two corresponding lower rollers 11. Figure 3A shows a side view of the preferred embodiment of the metal curling device of the present invention in the direction of section A-A on Figure 2. Figure 3B shows a side view of another preferred embodiment of the metal curling device 5 having four upper rollers 10 and four corresponding lower rollers 11 from a side where the metal strip enters the metal curling device 5. The lower roll 100 is arranged below the upper roll 110 at a variable distance for adapting the pressure for driving the metal strip 3. The upper roll 100 and the lower roll 110 are vertically adjustable by a mechanical or hydraulic adjusting means 25 for effecting proper spacing between the upper and lower rolls 100, 110 corresponding to the thickness t of the metal strip 3 to be passed therebetween for being advanced by the upper roll 100 and the lower roll 110 toward the buttress roll 130. The upper roll 100, the lower roll 110 and the buttress roll 130 are constructed of a plurality of individual rollers 10, 11, 13 arranged with their rolling axis substantially perpendicular to the longitudinal axis of the metal strip 3. The lead roll 120 is made of a single cylindrical roller 12 arranged with its rolling axis substantially perpendicular to the longitudinal axis of the metal strip. Alternatively, the lead roll 120 may be made of a plurality of individual rollers 12. Individual rollers 10, 11, 13 of each roll 100, 110, 130 are arranged adjacent to each other in a direction at a substantially oblique angle to the feed path of the metal strip 3 such that the metal strip 3 is curled by the rolls 100, 110, 120, 130 into helical convolutions, wherein the adjacent rollers 10, 11, 13 are arranged shifted and/or offset on the feed path. The rollers 10, 11, 13 of each roll 100, 110, 120, 130 may be arranged as in rows with parallel rolling axes to form rollers. Accordingly, the rollers 100, 110, 120, 130 may be arranged pivotally with respect to the frame 4 in order to change the angle their axes of rotation relative to the feed path of the metal strip 3. The upper roll 100 and the lower roll 110 comprise driven rollers 10, 11 that are driven by drive means 8.

The metal curling device 5 comprises a beam 14 supporting the upper roll 100 at a first end portion of the frame 4 from which the curled metal strip 4 extends in the production direction P towards a second end portion of the frame 4 opposite to first end portion. The beam 14 is arranged vertically movable with respect to the frame 4 to adjust the distance between the upper roll 100 and the lower roll 110 according to the thickness t of the metal strip 3. The beam 14 is supported by a substantially vertical column 15 arranged at the first end portion of the frame 4. The frame 4 comprises a table 16 supporting the lower roll 110 below the upper roll 100. The table 16 is arranged vertically movable with respect to the frame 4 to adjust the distance between the upper roll 100 and the lower roll 110. Figure 4 shows a preferred embodiment of a driven roller according to the present invention. The driven roller 10, 11 comprises an electric motor 17 as drive means. The electric motor 17 is arranged to drive the driven roller 10, 11 via a transmission 19 having a planetary gearing 20. The transmission 19 is arranged at least partially inside the driven roller 10, 11. The driven roller 10, 11 comprises a housing 21 to support the driven roller 10, 11 and the transmission 19. The electric motor 17 is mounted at the housing 21 to drive the driven roller

10, 11. The housing 21 is arranged to be supported at the beam 14 and the table 16 on the frame 4. The housing 21 comprises a pair of side flanges 22 at which part of the transmission 19 is arranged. The driven roller 10, 11 is arranged to roll between the side flanges 22, rotatably supported at the side flanges 22. The driven roller 10, 11 comprises internal teeth arranged on its inner surface to carry planet gears of the planetary gearing 20. The planetary gearing 20 is arranged completely inside the driven roller 10, 11. The electric motor 17 is arranged with its axis of rotation perpendicular to the axis of rotation of the driven roller 10,

11, wherein the transmission 19 comprises a worm wheel driven by the electric motor 17. The transmission 19 comprises a worm wheel at a first driven end and a planetary gearing 20 at a second driving end. Both side flanges 22 comprise part of the transmission 19 to drivingly support the driven roller 10, 11. The housing 21 comprises a cover 23 connecting the side flanges 22 at which the electric motor 17 is supported between the side flanges 22. The electric motor 17 is arranged at a radial side of the driven roller 10, 11. The housing 21 comprises pivoting means 24 on the cover 23 to rotatably support the driven roller 10, 11 at the beam 14 and the table 16 on the frame 4.

Accordingly, a preferred embodiment of the invention comprises a drive roll 100, 110 (shown in Figures 1, 2, 3 A and 3B) comprising driven rollers 10, 11 as shown in Figure 4 to advance the metal strip 4 on the feed path in the feeding direction F by engaging the metal strip on a substantially planar surface thereof. Driven rollers 10, 11 comprise electric motors 17 as drive means 8 to drive the driven roller 10, 11. The electric motors 17 are mounted at the drive roll 100, 110 such that they are arranged on the feed path above and below the metal strip 4. The drive roll 100, 110 comprises a plurality of driven rollers 10, 11 arranged adjacent to each other with their axis of rotation parallel to each other and offset and shifted in the feeding direction F. The drive roll 100, 110 is resizable such that to include variable number of driven rollers 10, 11.

The pipe production apparatus shown in Figures 1, 2, 3 A and 3B comprise the drive roll shown in Figure 4 as the upper roll 100 and the lower roll 110 arranged at the metal curling device 5, frame 4 or carriage 2 thereof to advance a metal strip 4.

The design features of the device, such as the number and the location of the rollers, size and orientation of the parts and joint types and materials, may all be adapted according to different cases appropriately.

The preferred embodiment of the invention is described above in the Drawings and Description of Preferred Embodiments. While these descriptions directly describe the above embodiments, it is understood that those skilled in the art may conceive modifications and/or variations to the specific embodiments shown and described herein. Any such modifications or variations that fall within the purview of this description are intended to be included therein as well. Unless specifically noted, it is the intention of the inventor that the words and phrases in the specification and claims be given the ordinary and accustomed meanings to those of ordinary skill in the applicable art(s). The foregoing description of a preferred embodiment and best mode of the invention known to the applicant at the time of filing the application has been presented and is intended for the purposes of illustration and description. It is not intended to be exhaustive or to limit the invention to the precise form disclosed, and many modifications and variations are possible in the light of the above teachings. The embodiment was chosen and described in order to best explain the principles of the invention and its practical application and to enable others skilled in the art to best utilize the invention in various embodiments and with various modifications as are suited to the particular use contemplated.

Claims

1. A pipe production apparatus for helically forming a metal strip comprising a carriage for carrying a substantially planar metal strip in a feeding direction on a feed path and a frame arranged adjacent to an end of the carriage supporting a metal curling device for receiving the metal strip, curling the metal strip and advancing the curled metal strip in a production direction that makes an angle with the feeding direction to form a pipe in the production direction, characterized in that the metal curling device comprises drive means at the frame to advance the metal strip in the feeding direction.

2. The pipe production apparatus according to claim 1, wherein the metal curling device comprises at least an upper driven roller and/or a lower driven roller that is driven by the drive means to rollingly engage a substantially planar surface of the metal strip.

3. The pipe production apparatus according to claim 1, wherein the metal curling device comprises an upper roll having at least an upper driven roller that is driven by the drive means to rollingly engage a top surface of the metal strip from above and a lower roll having at least a lower driven roller that is driven by the drive means and arranged below the upper driven roller to rollingly engage a bottom surface of the metal strip opposite to the top surface from below, such that the metal strip is compressed between the upper driven roller and the lower driven roller, preferably wherein the lower roll is arranged below the upper roll at a variable distance for adapting the pressure for advancing the metal strip.

4. The pipe production apparatus according to one of claims 2 or 3, wherein the metal curling device further comprises a lead roll for receiving the metal strip thereon, and a buttress roll on the opposite side of the upper drive roll and the lower drive roll from the lead roll engaging the same surface of metal strip as the lead roll, wherein the upper driven roller and the lower driven roller are arranged between the lead roll and the buttress roll.

5. The pipe production apparatus according to one of claims 1 to 4, wherein the drive means comprises an electric motor and/or wherein the drive means is arranged on the feed path above and/or below the metal strip.

6. The pipe production apparatus according to one of claims 3 to 5, wherein the upper roll and the lower roll are resizable to include variable number of upper driven rollers and lower driven rollers.

7. A metal curling device for helically forming a metal strip comprising: a lead roll for receiving the metal strip thereon; an upper roll, which is disposed internally of the path of the curled metal strip, a lower roll which is disposed externally of the path of the curled metal strip, such that the metal strip is passed between the upper roll and the lower roll; and a buttress roll on the opposite side of the upper roll and the lower roll from the lead roll engaging the same surface of metal strip as the lead roll; characterized in that a drive means is arranged to drive the at least one of the upper roll and the lower roll to advance the metal strip from the lead roll between the upper roll and the lower roll and toward the buttress roll.

8. The metal curling device according to claim 7, wherein the drive means comprises an electric motor to drive the upper roll and/or the lower roll to advance the metal strip, preferably wherein the arranged at the electric motor is arranged at the upper roll and/or the lower roll.

9. The metal curling device according to claim 7 or 8, wherein the lower roll is arranged below the upper roll, preferably at a distance variable by an adjusting means for adjusting spacing between the upper and lower rolls depending on the thickness of the metal strip.

10. The metal curling device according to one of claims 7 to 9, wherein at least the upper roll, the lower roll and/or the buttress roll are formed by a plurality of individual rollers, preferably arranged with their rolling axis substantially perpendicular to a feed path of metal strip.

11. The metal curling device according to one of claims 7 to 10, wherein the upper roll and the lower roll are resizable such that to include variable number of upper driven rollers and lower driven rollers.

12. The metal curling device according to one of claims 7 to 11, wherein the upper roll and the lower roll comprise the upper driven rollers and the lower driven rollers respectively, preferably wherein the upper driven rollers and the lower driven rollers are arranged removable and/or repositionable on the beam and on the table respectively.

13. A pipe production apparatus for helically forming a metal strip comprising a carriage for carrying a substantially planar metal strip in a feeding direction and a frame arranged adjacent to an end of the carriage supporting a metal curling device according to one of claims 7 to 12 for receiving the metal strip, curling the metal strip and advancing the curled metal strip in a production direction that makes an angle with the feeding direction to form a pipe in the production direction.

14. A drive roll for a metal curling device to advance a metal strip on a feed path in a feeding direction comprising at least a driven roller to engage the metal strip on a substantially planar surface thereof characterized in that a drive means is arranged on the feed path to drive the driven roller.

15. The drive roll according to claim 14, wherein the drive means comprises an electric motor, preferably arranged to drive the driven roller via a transmission, preferably via a planetary gearing.

16. The drive roll according to claim 15, wherein the transmission is arranged at least partially inside the driven roller.

17. A drive roll according to one of claims 14 to 16, wherein the driven roller comprises a housing to support the driven roller and the transmission, wherein the electric motor is mounted at the housing and wherein the housing comprises side flanges between which the driven roller and the electric motor is arranged.

18. A drive roll according to one of claims 14 to 17, wherein the drive roll comprises a plurality of driven rollers arranged in a row and offset and/or shifted in the feeding direction.

19. A drive roll according to one of claims 14 to 17, wherein the drive roll is resizable such that to include variable number of driven rollers.