Abstract: Spiral forming methods can be used to join edges of a rolled material along a spiral joint to form conical and/or cylindrical structures. Alignment of the edges of the rolled material can be controlled in a wrapping direction as the material is being joined along the spiral joint to form the structure. By controlling alignment of the edges of the material as the edges of the material are being joined, small corrections can be made over the course of forming the structure facilitating control over geometric tolerances of the resulting spiral formed structure.

Abstract: Apparatus (1) for forming in continuous a spiral seamed conduit (5) from a metallic strip (2) comprising a feeding plane (3) for said metallic strip (2); a forming head (4,4?) rotating about a forming axis (A) substantially parallel to the feeding plane (3) and tilted by a forming angle (a) with respect to a direction orthogonal (0) to a feeding direction (F) of the metallic strip, wherein the forming head (4,4?) is adapted to drive in rotation said metallic strip (2) for defining a spiral conduit (5); a lock-seaming device (6) configured to lock in continuous two portions of said metallic strip (2) along opposite profiles for forming said spiral seamed conduit (5); wherein said forming head (4,4?) is provided with one or more forming elements (7,9) arranged and configured so to define a substantially polygonal shape for the section of said spiral conduit (5) during the drive in rotation of said metallic strip (2); wherein said lock-seaming device (6) is configured to move along a seaming direction (G) so to

Abstract: An assembly for covering at least a portion of a cable, such as an electric cable, comprises an elastomeric tube and a hybrid support core structure. The hybrid core structure includes a central core structure formed from a spirally wound separable ribbon that supports a central portion of the elastomeric tube in a radially expanded state, and first and second solid end core structures that support first and second end portions of the elastomeric tube in a radially expanded state. Each solid end core structure has a film disposed on at least an inner surface thereof having a coefficient of friction less than or equal to 0.05.

Abstract: An apparatus (50) for and method of manufacturing helically wound tubular structures (116) includes a rotating faceplate (74) upon which are mounted a plurality of diameter defining rollers (78) which, in operation, cause a strip material (80) to be plastically deformed into a helical winding which may be lain down in abutting or self-overlapping relationship to form said tubular structure (116).

Abstract: Provided is a manufacturing method of a spiral duct including an elbow. The manufacturing method includes: bending projecting wave portions of metal plate members upward by a ball caster, the metal plate members being cut in such a manner that a straight lines and waves are formed; transferring the metal plate members using a pair of transfer rollers which are rotated by a first motor installed in a manufacturing apparatus of a spiral duct including an elbow; pressing a single folded portion and a double folded portion of the metal plate members using upper and lower pressing rollers while the transferred metal plate members are rolled into a circular shape by a joint jig; and cutting the elbow formed by the manufacturing apparatus using upper and lower cutters. According to the invention, an elbow curved at a gentle angle can be formed, and the projecting wave portions of the metal plate members are bent so as to form the elbow. Therefore, a fluid can smoothly flow along the curved portion of the elbow.

Abstract: An apparatus for forming a carcass for encasing a tubular member including a driven rotor (20) having a front face rotatable about a pivot axis and a spool mandrel (38) positioned eccentrically on the driven rotor (20). The spool mandrel (38) is adapted to rotatably mount a roll of coiled strip material (32). The rotor (20) includes at least one counterweight (60) mounted on the front face that is dynamically movable to at least partially balance the changing weight of the roll of strip material as the strip material (32) is removed from the roll. At least one pusher roll assembly (75) is mounted on the front face and contacts a portion of the strip material (32) to partially deform the coiling of the strip material as the material is removed from the roll. An anti-kink roll assembly (90) prevents kink deformation of the strip material (32) during the formation of the carcass.

Abstract: A system is configured for forming a flange at an end of a tube. The system includes a collar configured to receive the tube. A first roller engages the collar and a second roller is configured to cooperate with the first roller to rotate the collar and the tube. A rotatable cam is disposed about the second roller and includes a cam surface configured to bend the end of the tube to thereby form the flange. The collar may be configured to restrict axial movement of the tube relative to the collar. Additionally or alternatively, the collar may be configured to restrict rotational movement of the tube relative to the collar.

Abstract: In an embodiment, a long reinforcing material-attached profile strip (100) in which joint portions are formed at both side edge portions and to which a reinforcing material continuously formed in the longitudinal direction is attached is supplied, and mutually adjacent joint portions are joined to each other, thereby producing a spiral pipe (S). A curl-forming apparatus (3) includes a sending roller for the reinforcing material-attached profile strip (100) and a curl guide. Using the curl-forming apparatus (3), adjacent parts of the reinforcing material-attached profile strip (100) are subjected to plastic deformation to form spirals by being provided with arc-like curls having a radius of curvature substantially similar to or not greater than the radius of curvature of the spiral pipe (S). Accordingly, the spiral pipe (S) can be produced while suppressing the action of a restoring force that restores the reinforcing material-attached profile strip (100) to its original radius of curvature.

Abstract: In an embodiment, a long reinforcing material-attached profile strip (100) in which joint portions are formed at both side edge portions and to which a reinforcing material continuously formed in the longitudinal direction is attached is supplied, and mutually adjacent joint portions are joined to each other, thereby producing a spiral pipe (S). A curl-forming apparatus (3) includes a sending roller for the reinforcing material-attached profile strip (100) and a curl guide. Using the curl-forming apparatus (3), adjacent parts of the reinforcing material-attached profile strip (100) are subjected to plastic deformation to form spirals by being provided with arc-like curls having a radius of curvature substantially similar to or not greater than the radius of curvature of the spiral pipe (S). Accordingly, the spiral pipe (S) can be produced while suppressing the action of a restoring force that restores the reinforcing material-attached profile strip (100) to its original radius of curvature.

Abstract: A tube, which is especially employed for making the main frame tube of a bicycle, is fabricated by means of a 6-4Ti alloy sheet being fed to the forming mold with a feed device, being cold-rolled with the stamping block, winding the circumferential side of the forming mold as a tube blank with a spiral clearance extending along the tube blank, and welding the tube blank at the spiral clearance as a seam of the finished tube. In this way, the fabricated tube has an advantage of providing a high strength to resist being deformed easily.

Abstract: A method for manufacturing a circular metal tank, from an elongated sheet of metal. The upper and lower longitudinal edges of the metal sheet are bent to produce a first “L” bend and a second “chair” bend, respectively. The sheet of metal is moved in a helical trajectory such that the second bend comes into proximity above the first bend. The second bend and the first bend are welded together such that the wall of the cylindrical tank is formed. Welding of the bends serves to stress relieve or anneal the bent metal, thereby preventing cracks in the metal which may result in leaks and/or compromise the structural integrity of the tank. The first and second bends additionally cooperate to form a helical roller track on the outside of the tank. The tank is supported and rotated about its longitudinal axis on a plurality of rollers that engage the roller track.

Abstract: Many types of stabilized lock-seam tubing are provided, as well as devices, apparatus and methods for producing such stabilized tubing. Advantageously, pinch-locked tubing according to the invention, which comprise interlocking, spaced pinched deformations of the lock-seam, greatly resists side-slip and other shape deformations, including those typically produced by cutting the tubing, and by ovalizing it. Many permutations of lock-seam pinching rollers and related devices for producing stabilized lock-seam tubing are provided. Pinch roller assemblies of the invention are suitable for use with conventional machines as well as machines adapted specifically for them. Apparatus of the invention are suitable producing helically wound or straight lock-seam tubing.

Abstract: Provided are an apparatus and method for manufacturing a spiral duct in which straight connection parts are integrally formed with both ends of a curved duct. Further provided are an apparatus and method for manufacturing a spiral duct capable of improving cutting quality of a metal band and precisely and securely coupling bent parts of edges of the metal band. The apparatus comprises a cutting roll to cut a metal band into two parts, the cutting roll having a horizontal rotation angle that can be varied to cut along a straight or a waved line in order to form a duct having straight and curved parts, and in order to adjust a diameter of the duct. In addition, the apparatus includes rolls for forming bent parts at edges of the cut metal bands, and for winding and seaming edges of the metal bands to form ducts.

Abstract: An apparatus (50) for and method of manufacturing helically wound tubular structures (116) includes a rotating faceplate (74) upon which are mounted a plurality of diameter defining rollers (78) which, in operation, cause a strip material (80) to be plastically deformed into a helical winding which may be lain down in abutting or self-overlapping relationship to form said tubular structure (116).

Abstract: A pipe manufacturing system and method for producing helically corrugated metal pipe is provided. The system and method utilize controlled profile formation.

Abstract: An optical output coupler having a reflector integrated in an evanescent coupler. In one aspect of the present invention, an apparatus according to an embodiment of the present invention includes first and second optical paths. An optical beam is to be directed through the first optical path. The apparatus also includes an evanescent coupler, which evanescently couples the first and second optical paths. The apparatus further includes a reflector, which is included in the evanescent coupler and integrated in the first and second optical paths. The optical beam that is directed through the first optical path is reflected from the reflector as the optical beam is concurrently evanescently coupled from the first to the second optical path.

Abstract: An optical output coupler having a reflector integrated in an evanescent coupler. In one aspect of the present invention, an apparatus according to an embodiment of the present invention includes first and second optical paths. An optical beam is to be directed through the first optical path. The apparatus also includes an evanescent coupler, which evanescently couples the first and second optical paths. The apparatus further includes a reflector, which is included in the evanescent coupler and integrated in the first and second optical paths. The optical beam that is directed through the first optical path is reflected from the reflector as the optical beam is concurrently evanescently coupled from the first to the second optical path.

Abstract: An apparatus for producing wrapped slip tubes from ribbon material (3), which consists of metal at least in part, comprising a profiling device (4) for forming seam edges (3a, 3b) of the ribbon material (3), at least one guiding surface (6a) for guiding the ribbon material (3) provided with the seam edges (3a, 3b), a bending device for deforming the ribbon material (3) into a helical partial surface of a cylindrical shell by of a deforming surface (7), a seam closing device (12) for closing the seam edges (3a, 3b) when inserted into one another by pressing them together, and a cutting device (15) for cutting produced tube portions off. Since the deforming surface (7), and preferably the at least one guiding surface (6a) also, comprises a contact surface of plastic material, pollution and damages of the tube can be avoided when producing it.

Abstract: In a method of manufacturing a helically-wound lock-seam tube for a ventilation duct system, the tube is provided with a plurality of air nozzles through its wall. The method involves the steps of: feeding a strip of sheet metal from a supply to a punching and pressing unit; punching and pressing the strip in the punching/pressing unit to form two rows of spaced openings through the strip; feeding the punched strip to a roller unit, in which a longitudinal bead is formed in the strip; feeding the punched and beaded strip to a forming head in which the strip is helically-wound to form a tube having a helical lock seam; feeding the helically-wound lock-seam tube out of the forming head; and cutting the tube into desired lengths. The apparatus has components for carrying out the various method steps, and the finished tube is provided with a desired pattern of air nozzles.

Abstract: A machine for producing spiral seamed hollow pipe having a central axis from a metal strip having a first side which becomes the inside surface of the spiral pipe, a second side which becomes the outside surface of the spiral pipe, a width, and two outer edges. The machine includes a being roller station wherein the metal strip is formed into a helix using rolling contact. As the strip is driven through the bending roller station the strip is continuously bent on a bending line which is parallel to the central axis of the spiral pipe and which extends across the metal strip at an angle offset from a right angle with reference to the outer edges of the strip. Within the bending roller station there are a plurality of rollers organized as what may be viewed as staggered roller segments extending across the strip along the bending line which is offset from a right angle. At the same time, the rotational axes of the rollers are perpendicular to the strip.

Abstract: The invention concerns a method for the continuous production of a flexible tube body from two stapled wires (9, 10) individually bent in bending means (7, 8), three stitches, unsupported by a mandrel, and such that wires (9, 10) remain constantly in contact so as to optimize their resistance to external pressure. Bending means (7, 8) can be arranged with respect to each other without affecting the bending adjustment. The method consists in stapling the two spirals by elastically deforming the turns so that one crosses the other to cause the wires to overlap partially. The invention also concerns an equipment for producing a flexible tube body.

Abstract: Apparatus for forming tapered spiral tubes from strips, is disclosed. The apparatus comprises a spiral tube forming system for forming a strip into a spiral tube; a strip infeed system adapted for feeding a strip to the pipe forming system; and computer-controlled means for continuously varying the angular orientation of the tube forming system relative to the strip infeed system to selectively vary the diameter of the forming tube. The selective variation of the diameter includes linearly tapered and curved profiles, as well as constant (unchanging) diameter profiles and combinations thereof.

Abstract: A cylindrical helical seamed metal tube wherein the seam thereof is at an angle of between 1 and 25 degrees with respect to the axis of the tube. A method of making the tube comprises the steps of continuously feeding the metal strip into a tubing former to form the metal strip into a helical tube with the leading and trailing edges juxtaposed, the feeding such that the strip longitudinal axis is at a substantially constant acute angle with respect to the tube longitudinal axis of between 1 and 25 degrees. After the tube is substantially formed, applying pressure on at least the leading edge, leading portion, trailing edge and trailing portion in the direction of the cylindrical wall such that same substantially conform to the cylindrical wall. The juxtaposed leading and trailing edges are fused together to form a fused seam, and maintained in a juxtaposed position until the seam cools sufficiently to maintain the juxtaposed position. An apparatus for making the tube is also provided.

Abstract: In a method for producing helically wound lock-seam tubing, a metal strip is fed to a forming head in which the tubing is formed. In order to prevent lock-seam slip, a clinching roller device form interlocking spaced deformations on the lock-seam. An apparatus for such production comprises a clinching roller provided with a recess for forming the deformations against a counter roller.

Abstract: In a method for producing helically wound lock-seam tubing, a metal strip is fed to a forming heed in which the tubing is formed. In order to prevent lock-seam slip, a clinching roller device forms interlocking spaced deformations on the lock-seam. An apparatus for such production comprises a clinching roller provided with a recess for forming the deformations against a counter roller.

Abstract: A bent pipe is made of a metal strip having one edge in a straight line and the other edge in a curved line by winding it helically. A double fold and a single fold are formed along the straight edge and the curved edge, respectively. Then the metal strip is wound helically so that the narrow portions will be in juxtaposition with one another.

Abstract: The invention provides that a strip of flat steel is formed at its edges with channels which face in opposite directions and the strip is perforated between the channels. The strip is spirally coiled into tube form and a flange of one of the channels engages in the other channel and the adjacent flanges are crimped to form a helical seam in the finished tube. The tube is cut to lengths and the lengths are used in filter elements. The channel flanges are deformed prior to spiralling to facilitate the crimping and the spiralling is enhanced by the use of forming plates having edges which helically follow the curvature of the mandrel leaving a gap for the material so that the edges fit in one of the channels holding the edge of the strip captive until the strip is coiled and the captive edge is properly presented into the other channel. The machine provides a novel form of cutting head for cutting the tube to lengths, embodying a cutting tool which orbits the tube in performing the cutting.

Abstract: An apparatus for the spiral winding of tapes for the continuous production of tubes without a core and having an angular cross-sectional area. A tape is guided centripetally along a convexly curved conducting surface situated in the tube being formed, the intake side of which conducting surface is located at the feed level. The centripetal guiding of the tape is suspended when the conducting surface reaches the outlet side for forming the excluding level segment of the tape.

Abstract: A method and a device for the spiral winding of tapes for the continuous production of tubes without a core and having an angular cross-sectional area. A tape is guided centripetally during each bending process along a convexly curved conducting surface situated in the region of the tube being formed, the intake side of which conducting surface is located at the feed level. The centripetal guiding of the tape is suspended when the conducting surface reaches the outlet side for forming the excluding level segment of the tape.

Abstract: A curved connecting pipe for ducts is proposed which can be manufactured at low cost. It is made by rolling spirally a long metal strip having wide portions and narrow portions alternately so that the wide portions will meet at one edge of the strip and the narrow portions will meet at the other edge. A single flange formed along one edge is received in a double flange formed along the other edge. An apparatus for making the connecting pipe is disclosed. In another embodiment, a flat edge of the strip is rested on a recessed edge and welded together.

Abstract: The invention concerns a device for the automatic cutting of circular tubes of small, medium and large thickness, obtained by gluing together several strips of fibrous, cellulose, metallic, or plastic materials, and generally speaking any materials in strips, and made by using a spiralizer, a profiler or an extruder.This device for automatic cutting is characterized by the fact that it comprises a fixed mandrel (2) on which the circular tube (4) coming from the spiralizer, profiler or extruder turns freely and is driven without constraint either side of the cutting line by counter-rollers (8, 9) subject to a rotary movement synchronized with the speed of rotation of the circular tube (4), this fixed mandrel (2) cooperating for the cut with at least one cutting group provided with a knife milled with two bevelled edges which are very sharp (43) which is immobile in rotation at the moment of cutting.The invention concerns disposable packs.

Abstract: Apparatus for helically curling longitudinally corrugated thin strip material into a flexible corrugated tube has a curling unit with driven input rollers forming a nip that matches the strip, and a cassette for a reel of the material which is connected to said unit and has strip guide rollers immediately adjacent the input rollers. The curling unit has driven output rollers on an upright support to drive the strip, and a spider which is vertically adjustable on the support and carries strip guide rollers which are on spindles equidistant from the longitudinal axis of the forming tube, and radially adjustable, so that adjustment of the spider on the support and the spindles on the spider permits the unit to form tubes of different diameters. A locking mechanism intermittently crimps overlapping parts of the forming tube. A bending device aids in forming relatively stiff strip stock, and also aids in forming softer stock into very small diameter tubes.

Abstract: An apparatus for producing multiple ribbed, spiral seamed pipe from a metal strip thinner than 29 gauge is disclosed. The apparatus includes the conventional elements of a frame, a drive roller for feeding the strip through the frame, a flange roller and folding finger for bending the outer edges of the metal strip, a forming head for forming the strip into a pipe so that the outer edges of the strip mate, and a clinching roller and contra roller for compressing the mated edges to produce a spiral seam. The present invention improves this conventional apparatus by providing only two pairs of edge forming roller assemblies that cooperate to bend the left edge of the strip perpendicular to the strip, and the right edge of the strip into an upward facing, V-shaped channel with its outer edge perpendicular with respect to the strip. Five pairs of corrugation rollers are mounted on the frame adjacent to the edge forming roller assemblies.

Abstract: This apparatus contains a plurality of die-forming roller pairs which form corrugations longitudinally in ductile strip material. The die-forming rollers are gear driven from an electric motor of adjustable speed. One die roller of each pair has an eccentric mounting to provide adjustment of the space between roller pairs. The side edges of the strip material are formed into an inside and an outside seam element. A pair of rotatably mounted curling rollers provides the corrugated strip material with the proper radius of curvature and helical angle for convolution into corrugated tubing. An adjustment means is provided which simultaneously sets the proper position both pivotally and laterally of said curling roller pair according to tubing diameter selected. Radially adjustable guide rollers guide the circumference of the strip during convolution. A pair of support rollers and a run-out table support the tubing as it is produced.

Abstract: The method of forming tubes from strip in which a complementary rib and groove are spaced apart to each extend longitudinally on the strip and oppositely facing on the said strip characterized by guiding the strip into a helical configuration to overlap the edges of the said strip, and pressing together the overlapping parts of the said strip while maintaining a differential pressure in the direction of feed to force the strip together under such differential pressure.

Abstract: A method for forming helically wound pipe from an elongated sheet of material having a longitudinal axis wherein markings are provided perpendicular to said longitudinal axis adjacent the edges of the elongated sheet of material at predetermined spaced intervals. The elongated sheet is fed in a direction parallel to its axis and wound helically to form a helically wound pipe having adjoining revolutions while maintaining the distance, parallel to said longitudinal axis, between successive indicia adjacent the edge of one revolution and the indicia adjacent the edge of the adjoining revolution constant.

Abstract: A method and apparatus for the continuous manufacture of reinforced, spirally wound pipe having a generally smooth inner wall produced from an elongated flat sheet of ductile material, such as galvanized steel, and one or more narrow strips of ductile material. The sheet and strips are situated in rolls located at the entry end of a rolling apparatus which is constructed to form one longitudinal, generally trapezoidal reinforced impression in the sheet corresponding to each of the narrow strips. In the process of forming the impressions, rolling stands in the rolling apparatus first fashion a longitudinal, generally rectangular channel in the sheet corresponding to each strip as the sheet progresses through the rolling apparatus. At the same time, the strips are shaped into reinforcement elements having an extended, continuous portion and splayed legs extending outwardly from the edges of the continuous portion.

Abstract: An apparatus and method for continuously forming multi-layer metal pipe from at least two elongated sheets of metal. One sheet is impressed with longitudinal corrugations in a rolling device and the second sheet, being uncorrugated, is then positioned contiguously upon the first, forming a multi-layer sheet. One or more removable modules is mounted in the rolling device to accurately align and guide the second sheet into position upon the first. Complementary portions of a single corrugation are then formed in the marginal edges of the multi-layer sheet and the sheet is spiralled into adjacent, helical convolutions in a pipe forming device, with the uncorrugated sheet forming the pipe interior. The adjacent convolutions are joined in a helical seam in the single corrugation by a seaming device located in the pipe forming device. In the primary embodiment of the invention, the seam is formed as a double lock seam along a neutral axis of the single corrugation.

Abstract: A readily adjustable machine which continuously produces corrugated flexible metal tubing from very light gauge metal and of various diameters. A warping ring receives therewithin a longitudinally corrugated narrow strip of formable metal of light gauge and warps the same helically to produce convolutions by means of a helical warping surface which extends into one of the longitudinal corrugations. The size of the tube produced can be varied by merely substituting a warping ring of a different size. A uniquely shaped pair of die-forming rollers have lock-seam forming surfaces which are adjustable relative to each other to provide variation in the degree to which the seam will permit and withstand axial torque. The lock seam is constructed to be symmetrical about the neutral axis of the corrugation and about the slope line of the common corrugation leg of adjacent convolutions which it constitutes.

Abstract: A readily adjustable machine which continuously produces corrugated flexible metal tubing from very light gauge metal and of various diameters. A warping ring receives therewithin a longitudinally corrugated narrow strip of formable metal of light gauge and warps the same helically to produce convolutions by means of a helical warping surface which extends into one of the longitudinal corrugations. The size of the tube produced can be varied by merely substituting a warping ring of a different size. A uniquely shaped pair of die-forming rollers have lock-seam forming surfaces which are adjustable relative to each other to provide variation in the degree to which the seam will permit and withstand axial torque. The lock seam is constructed to be symmetrical about the neutral axis of the corrugation and about the slope line of the common corrugation leg of adjacent convolutions which it constitutes.

Abstract: This invention relates to apparatus for manufacturing tubes by the helical coiling of a strip into successive convolutions. The strip is preferably of a corrugated sheet metal. The coiling means of the apparatus comprises a plurality of non-driven freely rotatable and radially adjustable guide rollers adapted to guide and support the strip during the formation of a convolution. These rollers are arranged on a circle so that they engage the convolution at its outside. Arranged at the point of the strip entry into the coiling means is an inner and an outer connecting roller, the inner connecting roller positioned within and the outer connecting roller positioned outside the circle on which the guide rollers are situated. The connecting rollers have the purpose of joining a convolution after its travel past the guide rollers to the incoming strip so that convolution and strip overlap each other.

Abstract: An apparatus for helically winding a strip of sheet metal into a large diameter pipe and connecting the edges of the strip by preforming and rabbeting. The edge bending for the rabbet is done in a preforming station and a rabbeting station in which the bends are sequentially and increasingly formed with multiple units at each station. Adjacent units are hinged and devices for adjusting the angular relationship between adjacent units are provided, including spacers and adjustable threaded devices. Gears permit driving multiple units at various adjustment angles.

Abstract: Corrugated, flexible, metal duct formed of a helically wound strip of lightweight metal characterized by a pair of interlocked U-shaped seam elements which constitute one leg of a common corrugation of contiguous convolutions of the strip and extend radially throughout the length of that leg so that the areas at the base of each U-shaped seam element abuts against the adjacent corrugation leg and is locked against separation thereby. Apparatus which makes such duct through the use of rollers only and void of any mandrel means is also shown.

Abstract: A corrugated pipe forming apparatus and method in which flat sheet metal is passed through a plurality of first and second opposite roller pairs and deformed into a corrugated sheet. Lateral lips are formed parallel to the edges of the sheet and extend generally perpendicular to the sheet over the full length thereof. A pipe rolling machine helically deforms the corrugated sheet and folds the lip into a mechanical lock seam defining Pittsburgh lock of predetermined dimensions and tolerances. To maintain such dimensions and tolerances the width of the lips is adjusted by simultaneously moving one roll of each set in identical increments towards and away from the other roll of each set to thereby correspondingly change the depth of the corrugations and the width of the lips. The sheet can be moved laterally to maintain the lips of equal width. Corrugating stations of the device are defined by opposed corrugating rollers with the upper rollers held on a first frame and the lower rollers held on a second frame.

Abstract: A machine and method for making spiral pipe from a continuous strip of sheet metal including a corrugating mill which forms corrugations in the strip and drives it through a three-roll bending mill which bends the strip into helical convolutions and guides adjacent edges thereof into an interlocking relationship and a pair of lock up rolls for crimping the interlocked edges of the convolutions into a continuous seam, which rolls are manually or automatically adjustable radially relative to the pipe axis whereby its diameter may be accurately controlled. Adjustment of said rolls radially inwardly effects a diameter increase whereas adjustment outwardly decreases the diameter of the pipe.