Abstract: Thin-wall, corrugated pipe having alternating, annular ridges and valleys along its length is bent between a pair of die parts selectively to reform the normal configuration of a valley and change the linear distance between segments of a pair of ridges adjacent said valley thereby to form an incremental bend in the pipe. Thereafter, a predetermined number of incremental bends are formed in consecutive valleys to obtain a desired angle of bend. A radial angle fixture is engaged on one end of the pipe to determine and maintain the radial position of the pipe during the bending of the pipe, and a bend angle protractor is provided to determine precisely the angle to which the pipe is bent. The radial angle fixture further serves to maintain the pipe entering the bending tool perpendicular to the plane of the pair of dies.

Abstract: A tube bending machine with rotary arms carrying a bending moment roller and a bending fulcrum roller has arm shafts mounted for axial movement. The arms are rotated for the tube bending action, whereby the bend so made in the tube lies in a predetermined non-planar arc. The arm shafts are turned by a pinion engaged by a rack and are moved axially by suitable pins engaged in cam slots with the rack and the cam slots all being moved simultaneously. In order to retain the tube in proper location or position during the trusts of non-planar arc bending there may be included more than one roller.

Abstract: A method for the manufacture of heat exchangers where tubes of rectangular section are assembled with dissipators for forming a plane core which is curved by applying a bending force on the small sides of the tubes, thereby making cores. These cores are assembled by engaging the ends of the tubes into tubular plates which are part of boxes.

Abstract: The invention relates to a process for the manufacture of a rigid, essentially elbow-shaped coaxial double pipe with a hollow space between inner and outer pipes, consisting of an elbow-shaped cold-bent high-pressure pipe for operating pressures of over 1000 bar as the inner pipe, the two shanks of the elbow each comprising a straight piece of pipe with a length of at least 5 times the outside diameter, and an elbow-shaped cold or hot-bent outer pipe which envelops the inner pipe in a manner as to leave an annular space between inner and outer pipes and extending the length of the outer pipe, with the outer pipe enveloping the bend and one straight shank only. Elbow-shaped coaxial double pipes of this type can, for instance, be part of a heat exchanger of up to 3000 m in length in the form of a coil type cooler comprising a plurality of straight pipes and U-shaped bends.

Abstract: A compact multiple coil heat exchanger having a high heat transfer density is provided to include at least an inner coil formed from a continuous tube into a plurality of contiguous turns about a common axis in a spiral arrangement and having a pitch in one direction and an outer coil formed from the continuous tube into a plurality of overlapping turns concentrically about the inner coil in a spiral arrangement having an opposite pitch. Further, a coil-forming apparatus and continuous coil-forming method is directed to form a multiple coil heat exchanger from a continuous tube using a coil-forming die rotatably mounted on a support frame. The coil-forming die includes a continuous spiral thread constructed to receive and laterally support the continuous tube while fabricating the multiple coil heat exchanger according to the continuous coil-forming method of this invention.

Abstract: A method and apparatus for forming wheel rims using a wheel rim blank having a well center region with a diameter equal to the diameter of the well center of the finished wheel rim. Two female die halves form a cavity to confine the wheel rim blank and two male dies cooperate with the female die halves to flare the bead seat regions of the wheel rim blank. The bead seat regions of the wheel rim blank are subsequently contoured to final dimensions between two additional female die halves by two additional male dies.

Abstract: A method of bending a long metal member of constant cross-section by locally heating a narrow zone on the periphery of said member by means of a heating collar (5) which surrounds said zone, by exerting thrust (2) on one end of the member and by supporting its other end by means of a pivoting arm (3). The temperature of the heated zone on the periphery of the member is kept substantially constant by detecting the temperature of this zone or the size of the gap which separates the heating collar from the periphery of said zone at at least two points around said periphery, one of these points being nearest the center of curvature and the other being on the opposite side to the first.

Abstract: A method and hot bending apparatus for metal pipes in which the temperature of the pipe is kept constant during "gradation bending". The temperature may be adjusted by adjusting the power applied to the heater, or alternatively by adjusting the relative movement of the pipe with respect to the heater. While a feedback system may be utilized, a predetermined program is preferred under control of a microprocessor.

Abstract: This invention relates to improved apparatus and process for manufacture of tunnel modules and tunnel sections used to build underwater tunnel tubes. A collapsible fixture is situated to roll up flat steel plate into a circular shell for the tunnel modules. A hydraulic cylinder is utilized to adjust the diameter of the fixture without collapsing it, in order to close any gaps between the ends of the plate when it is rolled into a shell.

Abstract: An improved collapsible fixture for fabrication of tunnel modules and tunnel sections for building underwater tunnel tubes is provided. The fixture has a series of shell-like support members along its length, each member having a stationary base portion, two rotatable side portions and a connecting foldable linkage portion. A common truss is connected to each of the foldable linkage portions and is activated by a plurality of hydraulically operated cylinders connected to the wheel core member of the fixture. In order to collapse the fixture, moveable radial spoke members in the shell-like support members are connected to sliding plate members which are moveably attached to hub plates on the wheel core member.

Abstract: A method and apparatus for bending straight pipe sections which are of predetermined length including cutting at a preset angle, bending, and calibrating to form a finished elbow.

Abstract: A method of forming a permanent curve in a length of convoluted wire-reinforced flexible plastics tubing comprises the steps of first flexing the chosen region of the tube into a curve whose radius is tighter than that eventually desired; forcibly holding said region in said tighter than desired curves; applying to the tube an internal pressure which is insufficient to burst the tube but which is high enough to strain the wire-reinforcement, the tube material, or both, in the bend region beyond its or their elastic limit; maintaining said internal pressure for a finite period of time; releasing the pressure; and finally releasing the tube from its preheld curve.

Abstract: A hand operated bending apparatus is provided for the bending of metal such as tubing and bar by the application of a force to a sweep lever arm cooperating with a preset pivoted force link, thereby urging the metal to follow the contour of a forming die and automatically terminating the bending action at a preset point by the disengagement of the force link from the metal bar.

Abstract: The invention relates to a tube bending device, especially for thin walled tubes made from austenitic materials, e.g., for power engineering. The device consists of a pressure truck, adjustable gear, inductor heating coil, cooling section and a bending arm. The tube to be bent is positioned with one end on the pressure truck, and the second end fixed to the bending arm, and is freely placed in the inductor gear and axially moved in the inductor gear on guide rollers of an adjustable gear.

Abstract: An elongated bending core is inserted coaxially in an elongated outer tube. The core has at least one recess which extends along the elongation of the core. An elongated inner tube is inserted into the recess so that the inner and outer tubes together constitute a jacketed tube. The jacketed tube is bent about an axis which is normal to the longitudinal axis thereof to thereby bend the inner and outer tubes simultaneously.

Abstract: Material is drawn from a roll of flat stock, passed through a pipe forming machine, and welded to provide a continuous length of pipe which is stored in a variable size loop. Pipe is withdrawn from the loop by means of a series of pipe straightening and feeding rollers which feeds the pipe to a bending machine. The bending machine is suspended from an overhead platform for rotation about a vertical axis and carries a shearing cutter so that multi-bend pipe sections, such as automobile exhaust pipes, may be bent, severed and dropped onto a conveyor for inspection and disposition while the pipe is being continuously formed from the flat stock. Distance between bends and plane of bend are respectively controlled by the pipe feeder and the bend machine rotation. Differences between forming and bending rates are compensated by varying the amount of pipe in the storage loop.

Abstract: Method of producing tube bends of a given diameter and substantially uniform wall thickness from a straight tube having a diameter smaller than the given diameter, which includes re-shaping at least one end of the straight tube with a work-tool to form tangentially directed cylindrical leg extensions of equal tube bend cross section.

Abstract: Corrugated pipe is bent by pinching the spiral corrugations on one side of the pipe to decrease their pitch and increase their amplitude as compared to the undeformed corrugations on the opposite side of the pipe, thereby shortening the pipe on one side. A machine for effecting deformation of the corrugations includes inner and outer clamp mechanisms which provide an inner spiral rib extending partially around the inside of the pipe and a pair of outer spiral ribs extending partially around the outside of the pipe. The clamps include hinged together clamp sections which are pivoted by hydraulic cylinders between a pipe engaging position for bending the pipe and a release position permitting advancement of the pipe. The cylinders drive the outer ribs toward one another as well as inwardly into grooves of the corrugations where their force is opposed by the inner rib which acts against the inside pipe surface at a ridge of the corrugation.

Abstract: The disclosure relates to a method of bending elongated materials such as pipe by applying a compressive primary bending force to the material at locations on either end of the portion of the material to be bent and locally stimulating bending of that portion of the material by the application of heat or a secondary bending force. The end portions of the materials are engaged by clamps, each clamp having an arm extending normal to the principle axis of the material. The compressive primary bend force is applied by exerting a force on locations on the arms displaced from the principal axis of the material, which force tends to draw the ends of the arms together.

Abstract: A process for bending large pipes comprises the steps of progressively and inductively heating the wall of a pipe within the region to be bent. The penetration depth of the heat energy is varied over the circumference of the pipe through shielding. The inner radius of the pipe to be heated may initially be heated before the entire wall is differentially heated. Apparatus for carrying out the process is also disclosed.

Abstract: An apparatus for reducing the radius of the bend in a U-shaped tube comprises two squeeze dies and a back die. The back die is hollowed to form a chamber that accommodates the bent section of the tube and supports the entire circumference of the tube at the center of the bent section. Mating slide surfaces on the back die and the squeeze dies cooperate to extend the back die during squeezing in such a manner as to accommodate the longitudinal extension of the tube legs that results from the squeezing; i.e., there is no relative longitudinal movement between the squeeze dies and the tube legs. This arrangement enables relatively thin-walled tubes to be squeezed without undue deformation of the tube.

Abstract: A method of forming a tube by pushing it through a tilted die to form a bend or change circumferential variations in wall thickness.

Abstract: A method and apparatus of forming a tube by pushing it through a die to form high quality tubular fittings.

Abstract: A process and jig for field bending relatively large diameter plastic pipe, the jig being to guide the pipe at the point of tangency adjacent the bend after the pipe is heated and bent to form a smooth curvature to the desired radius and degree of bend as determined by the jig. The jig includes a two-piece spreader tube and a right and left hand guide, each adjustable in width, angle and spacing. The guides are U-shape and extend beneath the spreader tube so that the pipe may be placed on a flat horizontal surface. Each guide is provided with a protractor, one of which includes an offset scale so that offsets or curves with generally parallel tangents may be formed. The spreader tube includes a scale to ascertain the chord in terms of the radius for given degrees of bend.

Abstract: A process and a machine for bending elongated articles wherein the article is led progressively past a heating device heating a small band of the article, the bending taking place in said band, wherein for controlling the thickness of a wall portion lying in the bend one measures the longitudinal speed of said still unbent wall portion before this reaches the heating device and likewise the speed after this wall portion has passed the heating device, and adjusts the distribution of the temperature in the heating zone of the band by changing the heating pattern in dependence on the relation between said two speeds.

Abstract: A method for the controlled bending of a submerged pipeline is disclosed. The section of the pipeline which is to be bent is slightly elevated off the sea floor, preferably by buoys attached to the pipeline along its length. The end of the elevated section of pipeline is pulled in to the desired point of termination while a drag force is simultaneously applied to the elevated portion of the pipeline. The applied drag force should be sufficient to create a bending moment which causes the pipeline to bend along a well defined arc. Preferably, dragging means such as chains, cables, or clump weights extending from the pipeline to the sea floor are used to impose the necessary drag force on the pipeline and to control elevation of the pipeline above the sea floor.

Abstract: To fabricate a bent assembly of two metal tubes with one extending through and radially spaced within the other, the bending is done by inserting the smaller through the larger tube producing a tubular work assembly, clamping a leading work portion onto a bending forming die with the inner tube eccentric in the region to be bent against the die-adjacent inner wall portion of the outer tube, bending the region trailing the clamped portion by wrapping onto the bending die, while at (and immediately preceding) the point of feed onto the die the tubes are supported against collapse by a cylindrical mandrel in the smaller tube and a mandrel of crescent cross-section interposed between the large and small tube, in the plane of bending providing reaction support by a slideshoe bearing against the outer tube diametrically remote from the die; the mandrels being axially shiftably supported.

Abstract: An apparatus for manufacturing elongated curved tubular elements sequentially clamps longitudinally spaced end portions of a straight elongated tubular section, confines a central portion of the tubular section intermediate the clamped end portions between two dies, applies forces to at least one of the dies to displace the same and thus also the central portion of the tubular section in a predetermined direction and to a given extent with respect to the clamped end portions so that substantially S-shaped transitory portions of deformed cross-sectional shapes develop between the clamped end portions and the central portion of the tubular section, and restores the cross-sectional shapes of the transitory portions preparatory to sequential retraction of the dies and unclamping of the end portions of the tubular section by means of at least one mandrel which is introducible into the tubular section through at least one of the end portions thereof for passage into and through at least one of the transitory portio

Abstract: Method and apparatus for bending coated pipe including heating a specific area of the pipe coating by resistance heating to prevent damage at all areas of the pipe coating during bending of the pipe. The pipe bending equipment includes an upper bending die, and a lower pin up shoe and a lower strongback. The strongback has resistance heating means in a recess which is positioned over a specific area of the upper surface of the strongback, for heating the pipe coating prior to bending of the pipe. By heating of a relatively small specific area of the pipe coating, damage to the entire area of the coating is avoided.

Abstract: A means and method is provided for reducing radius expansion of bent, elongated materials due to "spring-back" occurring after the material is released from the bender clamps of a hot bending apparatus, wherein the longitudinal axis of the unbent portion of the material is displaced by a small angle from a perpendicular to a line running through the center of the bend and the bender heating means.

Abstract: The invention provides an improved method and apparatus for pipe bending. In the method a leading portion of a length of pipe is heated and bent around a mandrel into a pipe bend, whereafter it is hot calibrated or sized to finished dimensions and at the same time cut off and trimmed to size at both ends. In a machine for carrying out the method, there are a heating chamber and an interchangeable bending mandrel. At the end of the bending mandrel there is a horizontally functioning calibrating or sizing device. A severing device is both in front of and behind the calibrating device for cutting off and trimming the pipe bend, and the pipe bend is movable both longitudinally and/or transversely in the horizontal plane.

Abstract: A pipe bending apparatus includes a pivotable bending arm carrying a means for engaging the pipe including an outer clamp attached to the arm and an inner clamp contacting the pipe and slidable within the outer clamp.

Abstract: This invention relates to methods and apparatus for accomplishing bending work on long metal materials such as pipe, bar and rod.

Abstract: A method of continuously bending elongated materials may comprise engaging one portion of the elongated material with a guiding means and clamping a second portion of the elongated material in a clamping device driven to rotate with a movable axis of rotation perpendicular to a horizontal plane. A heated zone bounded by a cooled zone moving relative to the elongated material may be established in the material by suitable heating and cooling means disposed adjacent to the material. The elongated member may be driven to pass through the guiding means. Where a hollow elongated material is to be bent, a compressing means may be placed within the elongated material to inhibit deformation of the cross-section of the material. An apparatus for continuously bending elongated members may be comprised of plural means for performing the aforestated functions.

Abstract: To straighten firearm barrels with bores running out to muzzle ends, a barrel is bent at a transverse barrel plane at a distance of less than half the barrel length from the muzzle end to an extent and in a direction to bring the bore center axis at this barrel plane into line with a straight reference axis passing through the centers of the opposite bore ends.

Abstract: A means and method for bending elongated materials having a device for locally heating a portion of the material and a freely pivotable bending arm, is provided with a second arm for advancing the elongated material past the heating device and, in cooperation with the pivotable arm, exerting a bending moment on the locally heated portion of the material.

Abstract: A method and apparatus for bending tubular bodies, wherein elemental tubular sections are gradually shifted with respect to each other, without rotation, in a V-shaped bend from a central bend section. The apparatus includes two slidingly fitted supports for housing the tubular body to be bent, and a central triangular presser acting between the supports on the central tube section. The supports are gradually moved by the presser in opposite directions to define the tube sections that are actually shifted.

Abstract: A method of and apparatus for bending a double pipe comprising inserting a smaller diameter pipe into a pipe of larger diameter and coupling the two pipes together at one end, inserting a inner metal core and an outer metal core respectively into the inside of the inner pipe and between the inner and outer pipes, inserting the double pipe into a bending mold, fixing the pipe on a turntable on which the bending mold is rigidly affixed, fixing a section of the double pipe near the end into which the metal cores were inserted thus blocking movement of the fixed section in the radial direction, and driving the turntable in a radial direction while keeping the metal cores in a fixed position and applying a bending force on the double pipe toward the bending mold while pushing the inner pipe in an axial direction from the end into which the metal core was inserted.

Abstract: Device for bending thin-walled pipes from inside by embossing them with eccentric corrugations, comprising an expander block introducible into the pipe to the point of bend, the block being formed by a supporting shoe and a punch whose side facing the pipe has a toroidal surface following the shape of the desired corrugation and which is mounted on the shoe with a provision for positive movement in a radial direction to the pipe surface for making the corrugation on the pipe. In the cross-sectional plane of the pipe the punch has the shape of a ring which is open at the side of the shoe and is composed of individual elements around its parameter, each element being articulated to a movable member of one of the power cylinders whose axes are arranged radially to a cross-sectional plane of the pipe while their stationary members are connected with the supporting shoe.

Abstract: Method of bending thermoplastic pipes involving applying a source of heat to these portions of the pipe which are to be fashioned or shaped, applying a bending force to the pipe and cooling the bent pipe. The steps of the method are undertaken at one and the same location while the pipe is internally supported and has one end secured in a fixed position. Apparatus specifically designed to carry out such a method is also included.

Abstract: A rectangular tubing bender having a frame provided with an arrangement for locking in place a tube to be bent. Structure on the frame forms directly opposed depressions on opposite sides of the rectangular tube prior to bending of the tube adjacent the depressions for permitting a completely closed and square bend to be formed. The locking arrangement may be mounted on a carriage movable on the frame for bending the tube by moving same against a stationary forming point member subsequent to the formation of the depressions in the tube. Cam operated rockers are advantageously employed to form the depressions.

Abstract: An apparatus for terminating a subsea flowline at an offshore structure by providing a bend in the continuous flowline at the bottom of the offshore structure to provide an upstanding flowline end portion adapted to be secured to the offshore structure. A pipe bending device comprising a plurality of spaced cylindrical segments sleeved over a selected location on the flowline with adjacent segments pivotally interconnected to each other on one side of the flowline and end cylindrical segments pivotally interconnected to each other by a cylinder and piston means on the opposite side of the flowline. The device is fixed to the flowline at an end segment thereof. Actuation of the cylinder and piston means imposes a bending force on the flowline within the cylindrical segments for imparting a bend of selected radius to the flowline within the cylindrical segments.

Abstract: A method and apparatus is provided for bending elongated members such as pipe sections by the application of axial compression to both ends of a pipe section positioned between parallel guides. Preferably the apparatus comprises a pair of fittings with pivot mountings receivable in both ends of the pipe section, means for forcing the fittings toward each other in a direction axial of the pipe and for initially applying slight transverse pressure to the pipe section intermediate its ends in a direction radially outward with respect to the desired bend, and parallel planar guides on opposite sides of the pipe section.

Abstract: A process and a machine for bending elongated articles wherein the article is led progressively past a heating device heating a small band of the article, the bending taking place in said band, wherein for controlling the thickness of a wall portion lying in the bend one measures the longitudinal speed of said still unbent wall portion before this reaches the heating device and likewise the speed after this wall portion has passed the heating device, and adjusts the distribution of the temperature in the heating zone of the band by changing the heating pattern in dependence on the relation between said two speeds.