Abstract: A pipe grooving device having a plurality of geared cams uses synchronizing gears, each of which meshes with two of the geared cams, to synchronize the rotation of the cams which engage the pipe element to form the groove. The position of the groove relative to the end of the pipe is controlled by a stop body which incorporates a plate mounted ring which engages and disengages with a pipe stop surface on one or more of the cams to limit or permit cam rotation. The pipe stop body is positioned within a cup which receives the pipe element. The cup limits pipe end flare and limits the tendency of the pipe to go out of round during the grooving process. The device mounts on a powered chuck which turns the pipe element.

Abstract: A system and method for cleaning, protecting and lubricating hyperbolic rollers and bearings for bending, using air and oil, placed in a rotating rotor (1) that contains rollers (32) placed on bearings (34) and shafts (33) inside roller housings (30), where rollers (32) are positioned at an angle with respect to the bending axis and, as bending occurs they cause bending and also as rotor (1) rotates around the item being bent it straightens and feeds the item. Rollers (32) are placed on bearings (34) and are protected through rotational seals (35). The bearings' (34) area of rollers (32) inside the rotational seal (35) is supplied with air at pressure higher than the atmospheric, so that inflow of contaminants are inhibited, or is supplied with air enriched with oil so that bearings (34) are lubricated, and rotational seals (35) located next to bearings (34) of the rollers (32) allow the air flow from the area between the bearings towards the surrounding area.

Abstract: The present invention provides a pipe straightener, which consists of three roller wheel units and a restraining sleeve, wherein each of the roller wheel units is juxtaposed, and the roller wheel units enclose and are configured to form a long straight-formed passageway. The passageway is used to enable metal pipes to pass therethrough. The restraining sleeve encloses and covers each of the roller wheel units, thereby restraining each of the roller wheel units. Each of the roller wheel units is mainly structured from a wheel carrier and a plurality of roller wheels. One side of the wheel carrier is a first side, and the other side is a second side. The first side is adjacent to the passageway, and the second side is adjacent to the restraining sleeve.

Abstract: An artificial or modified natural blood flow tubing has a helical-flow inducer to induce helical flow in such a fashion as to eliminate or reduce turbulence. One inducer is a tubular stent of expansible mesh having a helical vane.

Abstract: A method of forming a housing which includes roll forming a steel tube radially inwardly with a plurality of rollers each having a rolling axis parallel to the longitudinal axis of the tube, the rollers compressing the tube and forming reduced diameter portions and enlarged diameter portions. The method then includes cutting the tube perpendicular to the longitudinal axis generally midway through an enlarged diameter portion and a reduced diameter portion, forming a plurality of minor image preforms. Finally, the method includes cold working the preforms into the desired shape of the housing and increasing the strength of the steel at least 15% and forming a housing member having enlarged diameter open end and a reduced diameter open end.

Abstract: A double-wall pipe includes an outer pipe, and an inner pipe disposed inside the outer pipe. An outer wall of the inner pipe has thereon a ridge portion, which defines a groove portion extending in a longitudinal direction of the inner pipe. The outer pipe and the inner pipe are bent to have a straight portion extending straightly, and a bend portion bent from the straight portion. In the straight portion, the outer pipe has an inside diameter that is larger than an outside diameter of an imaginary cylinder defined by an outer surface of the ridge portion of the inner pipe. Furthermore, the ridge portion of the inner pipe contacts an inside surface of the outer pipe to be readially squeezed and held by the outer pipe, in the bend portion. The double-wall pipe can be suitably used for a refrigerant cycle device.

Abstract: The invention relates to a rolling mill for rolling stock to be rolled (6), having a planetary cross-rolling mill (20) and a subsequent further rolling mill in the rolling direction, the subsequent mill comprising a mandrel rod (10) having a length that is larger than the distance between the planetary cross-rolling mill (20) and the further rolling mill in the rolling direction.

Abstract: Apparatus for reducing the diameter, rounding or straightening of pipe or tubing by rolling comprising a plurality of cylindrical rollers arranged in a parallel-cylindrical array through which the pipe or tubing is passed, the rollers being skewed to displace their central contact zones radially inwards bringing them into forceful contact with the external surface of the pipe or tubing, and being rotated to cause the central contact zones to describe helical paths along the external surface of the pipe or tubing. Thereby to progressively apply locally to the whole of the external surface of the pipe or tubing a compressive force in excess of the yield strength of its material, causing the pipe or tubing to adopt a set at a smaller diameter.

Abstract: Disclosed herein is a forming disk for fabricating a fin tube. The forming disk comprises a substantially circular plate having a shaft connection hole formed adjacent a center thereof for receiving a shaft of a form rolling machine. A plurality of projections having a first length are formed along a circumference of said plate at substantially regular angular intervals in such a way as to protrude in a radial direction, and a round curvature is formed in the formed fin at certain axial pitch periodically in a radial direction. Also disclosed is a high-performance and high-efficiency fin tube having formed fins. Each formed fin comprises a generally circular plate having a crest and a valley formed in both side faces at certain angular intervals along the circumference thereof so as to form a continuous curvature.

Abstract: A straightening rotor is provided with at least two freely positionable balancing means that are essentially arranged symmetrical to a central plane, axially relative to a rotational axis of the straightening rotor. This makes it possible to achieve higher speeds and/or a longer service life.

Abstract: A cylindrical rod 20 is formed by bending sheet metal 10 so as to bond together a pair of edges 12 and 14 of the sheet metal 10. The cylindrical rod 20 includes therein (i) convex portions 16 each of which protrudes from the edge 12 and includes a sub-portion whose width is larger at a side thereof more distant from the edge 12 than at a side thereof less distant from the edge 12, and (ii) concave portions 18 which are formed on the edge 14, have a shape complementary to the shape of the convex portions 16, and are fitted into the convex portions 16. A cylindrical rod which has high circularity and high linearity, in other words, which hardly has vertical and horizontal curves can be provided.

Abstract: In a device and in a process for bending a tube 72, the tube 72 is guided through a bending tool 71, which rotates around a section guide housing 81, 82 and also around a cam unit formed by two tubes 83, 84. Rollers 86 serve as pressing elements, and a mandrel 73 serves as an abutment; as the tube 72 is pushed through the section guide housing 81, 82 between the rollers 86 and the mandrel 73, it is squeezed to different degrees in different areas of its wall cross section, so that, as a result of the stretching and squeezing of the tube 72, a bend is produced. The size of the bending radius of the tube 72 to be bent is determined by the eccentricity adjusted via the cam unit and/or by the axial feed of the rollers 86 toward the section guide housing 81, 82. By means of the bending tool 71 according to the invention, it is possible to produce different bending radii in one and the same bending device in a tube 72 to be bent by changing the feed, that is, the distance between the rollers 86 and the mandrel 73.

Abstract: A roll shaft assembly especially for a planetary cross roll rolling mill for tubing and the like has the roll shaft and mill roll connected by a conical centering arrangement and a screw, preferably coaxial therewith with the torque transfer being effected by tooth rings on the ends of the shaft and roll and having interdigitating teeth.

Abstract: A machine may produce a tube having textured internal and external surfaces in a single operation. Inner and outer knurling tools may form the textured surfaces. The texturing of the internal and external surfaces may be helical patterns of ribs and grooves. The height of the ribs formed in the internal and external surfaces may be less than about 35 mils. The angles of the patterns relative to a longitudinal axis of the tube may be less than about 45°. The angle of the helical pattern allows textured tubes to be used as heat exchanger elements wherein flow is directed substantially coaxial to the longitudinal axes of the tubes. The helical pattern formed in the external surface may be oriented in a right hand or left hand helical orientation. Similarly, the helical pattern formed in the internal surface may be oriented in a right hand or left hand orientation.

Abstract: A method of reducing slot width in slotted tubular liners. A slotted tubular liner (1) is provided having an interior surface (3), an exterior surface (2) and a plurality of slots (4) extending between the interior surface and the exterior surface. One or more contoured rigid forming tools (7) are provided. Pressure is applied to either the interior surface (3) or the exterior surface (2) of the slotted tubular liner (1) with the contoured rigid forming tools (7). The contoured rigid forming tools are then moved in a sweep pattern traversing either the interior surface or the exterior surface of the slotted tubular liner, until plastic deformation narrows the width of the plurality of slots (4) to within desired tolerances. The method does not require the same precise positioning of previously known methods and, as such, provides a combination of increased output and lower cost.

Abstract: In the planetary skew rolling blooms to form seamless metal tubing or pipe the internal tool is retracted at the leading and/or trailing end of the tubular bloom to allow the rolls to seal the end or ends and prevent coolant from entering the rolled tubing or bloom. The internal tool is advanced back into its normal rolling position after the end has passed the rolling location.

Abstract: An arrangement for inclined rolling of tube-shaped or bar-shaped rolling products comprises at least two rollers adapted to receive therebetween a rolling product so as to determine a longitudinal axis of the rolling product, the rollers are driveable and are rotatable about said longitudinal axis. The rollers have roller axes inclined at an inclination angle relative to the longitudinal axis, the roller axes being inclined in such a plane which, when considered in or against the longitudinal axis, extends parallel to the longitudinal axis at a radial distance from it, and a driving unit for driving the rollers. The driving unit includes a sun gear and drive gears provided with an axis-offset bevel gear toothing and surrounding a respective one of the roller axes, the drive gears engaging with the sun gear so that the rollers are driven by the sun gear through the drive gears.

Abstract: A roll shaft assembly especially for a planetary cross roll rolling mill for tubing and the like has the roll shaft and mill roll connected by a conical centering arrangement and a screw, preferably coaxial therewith with the torque transfer being effected by tooth rings on the ends of the shaft and roll and having interdigitating teeth.

Abstract: A method of reducing slot width in slotted tubular liners. A slotted tubular liner (1) is provided having an interior surface (3), an exterior surface (2) and a plurality of slots (4) extending between the interior surface and the exterior surface. One or more contoured rigid forming tools (7) are provided. Pressure is applied to either the interior surface (3) or the exterior surface(2) of the slotted tubular liner (1) with the contoured rigid forming tools (7). The contoured rigid forming tools are then moved in a sweep pattern traversing either the interior surface or the exterior surface of the slotted tubular liner, until plastic deformation narrows the width of the plurality of slots (4) to within desired tolerances. The method does not require the same precise positioning of previously known methods and, as such, provides a combination of increased output and lower cost.

Abstract: A roller head for a planetary rolling arrangement, said roller head comprising a housing, inside which housing there is rotatably arranged a hollow outer axis and means for rotating said outer axis, as well as inside said outer axis, in a manner that transmits the rotary motion thereof, a center axis which is movable in the axial direction and can be locked in the axial direction, said center axis being provided with a roller. The roller head is characterized by an adjusting axis which is rotatably arranged at the end of the outer axis that is located on the opposite side with respect to the roller and is essentially locked in the axial direction said adjusting axis comprising a counterpart for the threaded section provided in the center axis, and said adjusting axis also including a locking member, which in the locking position forms a friction coupling at least between the adjusting axis and the outer axis.

Abstract: A method for producing a, in particular thin-walled, pipe conduit element with a surface structure reinforcing the pipe conduit element is proposed wherein the pipe conduit element continuously passes by at least one embossing element guided about the periphery of the jacket thereof and the surface structure is embossed onto the jacket of the pipe conduit element by the embossing element using pure mechanical pressure. For embossing the surface structure onto the pipe conduit element, an arrangement of preferably several embossing elements, in particular balls or rollers are used which are distributed about the periphery of the pipe conduit element jacket. The invention also concerns a device for producing a surface structured pipe conduit element using a guidance having embossing elements and which can be rotated about the periphery of the jacket of a pipe conduit element continuously supplied to the device.

Abstract: A method and apparatus for forming annularly-corrugated tubes and cables utilizing a multiple gear corrugating head which is rotated about the tube or cable, to be corrugated as the tube or cable is drawn through the head. Two or more of the gears each have a different prime number of gear teeth which form the corrugation.

Abstract: An apparatus for producing annularly corrugated metal tubes, particularly the outer conductor of coaxial high-frequency cables, using at least one pressure roller revolving around a plain tube. The corrugations are formed in the plain tube by the teeth of the pressure roller, which is rotatable about an axis at a 90° angle to the longitudinal axis of the tube, and the axis of rotation of the pressure roller, itself in a plane perpendicular to the longitudinal axis of the tube, revolves around the plain tube being fed to the pressure roller as the corrugations are produced. The plain tube in turn rotates the pressure roller by its feed. The tips of the teeth are substantially flat, the tube is tightly guided in a guide bushing (12) in front of and behind the engagement with the pressure roller (13), and the number of teeth (Z) ranges between 7 and 11, preferably between 8 and 10.

Abstract: A method and device for rolling tube blanks in a planetary skew rolling mill continuously feeds tubular blanks which are to be rolled into the rolling gap end to end. A first tube blank is located in the rolling mill. A second tubular blank following the first tubular blank which is respectively located in the rolling gap of the rolling mill is fed forward with a rotation corresponding to the rotation of the end of the first tube blank caused by the torsion under the rollers in the rolling mill.

Abstract: A roller head for a planetary rolling arrangement, said roller head comprising a housing, inside which housing there is rotatably arranged a hollow outer axis and means for rotating said outer axis, as well as inside said outer axis, in a manner that transmits the rotary motion thereof, a center axis which is movable in the axial direction and can be locked in the axial direction, said center axis being provided with a roller. The roller head is characterized by an adjusting axis which is rotatably arranged at the end of the outer axis that is located on the opposite side with respect to the roller and is essentially locked in the axial direction said adjusting axis comprising a counterpart for the threaded section provided in the center axis, and said adjusting axis also including a locking member, which in the locking position forms a friction coupling at least between the adjusting axis and the outer axis.

Abstract: A method and apparatus for forming annularly-corrugated tubes and cables utilizing a multiple gear corrugating head which is rotated about the tube or cable, to be corrugated as the tube or cable is drawn through the head. Two or more of the gears each have a different prime number of gear teeth which form the corrugation.

Abstract: An apparatus for continuous production of a helically corrugated metal tube (12, 14) includes a corrugator head (11), which is driven by a rotary drive and is freely rotatably supported eccentrically to the longitudinal axis of the metal tube (12, 14). The corrugating tool (16) includes at least one disk whose eccentric position relative to the longitudinal axis of the metal tube (12, 14) is adjustable and whose circumferential surface rolls off the metal tube (12, 14).

Abstract: An apparatus for producing annularly corrugated metal tubes, particularly the outer conductor of coaxial high-frequency cables, using at least one pressure roller revolving around a plain tube. The corrugations are formed in the plain tube by the teeth of the pressure roller, which is rotatable about an axis at a 90° angle to the longitudinal axis of the tube, and the axis of rotation of the pressure roller, itself in a plane perpendicular to the longitudinal axis of the tube, revolves around the plain tube being fed to the pressure roller as the corrugations are produced. The plain tube in turn rotates the pressure roller by its feed. The tips of the teeth are substantially flat, the tube is tightly guided in a guide bushing (12) in front of and behind the engagement with the pressure roller (13), and the number of teeth (Z) ranges between 7 and 11, preferably between 8 and 10.

Abstract: A method and device for rolling tube blanks in a planetary skew rolling mill continuously feeds tubular blanks which are to be rolled into the rolling gap end to end. A first tube blank is located in the rolling mill. A second tubular blank following the first tubular blank which is respectively located in the rolling gap of the rolling mill is fed forward with a rotation corresponding to the rotation of the end of the first tube blank caused by the torsion under the rollers in the rolling mill.

Abstract: In an apparatus for continuous corrugation of walls of tubes or tubular elements, especially cable components, at least one corrugating wheel, rotatable about its own axis, also rotates about the tubular element to be corrugated. In addition to a drive (15) for the rotation of the at least one corrugating wheel (11) about the tubular element (5) to be corrugated, there is provided a speed-controllable drive (16) for the rotation of the at least one corrugating wheel about its own axis.

Abstract: An arrangement for inclined rolling of tube-and bar-shaped rolling articles has two or more driven rollers rotatable about a longitudinal axis of a rolling article and supported in or on a rotor which surrounds the rolling article. The rotor is arranged in a stationary housing which is closed from all sides to provide a compact and efficient arrangement allowing an especially high rotary speed. Moreover, the arrangement with the inclined rollers rotatable about the longitudinal axis of the rolling product allow a fast exchange of the whole arrangement by a pre-assembled second arrangement so that stoppage of the whole arrangement during a roller exchange or a change in the roller adjustment is substantially reduced.

Abstract: The invention relates to a method for the better utilization of the working width of a profiling stone in the inner profiling of heat exchanger pipes. The press on width of the revolving roller bodies is substantially narrower than the profile width of the profiling stone so that in this area the profiling stone is worn out rapidly while the other area remains unworn since it is not utilized. In order to avoid this, the invention suggests that the press on rollers and the profiling stone is moved within the range of the working width of the profiling stone axially back and forth so that the entire profile range of the profiling stone can be utilized.

Abstract: A machine tool apparatus having a burnishing head assembly coupled directly to a hollow, tubular output shaft of the motor of the apparatus. The tubular output shaft is coupled to the armature of the motor and allows a cylindrical workpiece or part inserted into the burnishing head assembly to be received and fed coaxially through the motor. The burnishing head assembly is coupled to the motor such that rotation of the tubular output shaft of the motor causes a corresponding rotation of a plurality of rolls of the burnishing head assembly. When the rolls come into contact with a surface of the workpiece or part, they bear against the surface to effect a roller burnishing of the surface. In the preferred embodiment the rolls are set at a helix angle which causes the rolls to draw the workpiece or part through the tubular output shaft of the motor and burnishing head assembly once contact with the rolls is made, to thereby obviate the need for an individual to manually feed in the part.

Abstract: A roller burnishing device for sizing and/or finishing the external surface of a workpiece having a circular sectional contour by causing a relative rotation between the workpiece and a plurality of truncated conical rollers arranged within a head having a truncated conical inner surface. In this device, the head is made nonrotatable and instead a hollow cylindrical cage supporting the rollers within the head is driven in rotation to rotate the rollers at a high speed and the rollers are caused to orbit by driving the cage in low speed rotation thereby causing the rollers to make a planetary motion within the head.

Abstract: An inner grooving process for the tube expanding rolling type by which inner grooves such as wide width grooves or deep grooves which cannot normally be formed readily can be formed with a high quality using an equipment of a simple structure without deteriorating the operability. In the process, a drawing die having an exit hole of a fixed diameter and a floating plug having no bearing portion thereon are used. The floating plug and a grooved plug connected for rotation to the floating plug and having an outer diameter smaller than the diameter of the exit hole of the drawing die are inserted into a metallic tube and then the grooved plug is drawn to a location of the rolling member into the metallic tube by drawing and then retained at such location.

Abstract: The method of the invention relates to the manufacturing of tubes of a continuously cast or the like billet by means of cold working, wherein the temperature of the material rises to the recrystallization range due to the influence of the deformation resistance. The method is particularly related to the further working of billets made of non-ferrous metals such as copper, aluminum, nickel, zirconium and titanium, as well as of their alloys.

Abstract: A method for producing a heat transfer tube for single-phase flow having rows of discontinuous projections formed on the inner surface thereof along one or more spiral curves. Each projection has a circular, elliptic or a similar cross-section constituted by smooth curves at any desired height including the bottom thereof. The cross-sectional area of the projection progressively decreases towards the top of the projection.

Abstract: An apparatus for manufacturing a core wire for use in laying optical fibers over a long distance produces a plurality of continuous corrugated deep grooves in a wire that are capable of holding therein the optical fibers longitudinally along the peripheral surface of the wire. An endless raw wire material of circular cross section is formed by the apparatus into a wire of square cross section through plastic processing and thereafter the wire is formed into a core wire of a flower patterned cross section with a plurality of petals having corrugated deep grooves in the periphery thereof continuously longitudinally thereof through a rolling device. In addition, the core wire so constructed is formed into a core wire with spiral corrugated deep grooves formed in the peripheral surface thereof. The rolling means has forming rolls equal in number to the number of ridges of the square wire, and each such roll having two perfect corrugated convex portions formed widthwise on the peripheral surface thereof.

Abstract: A process and apparatus for bias rolling of strip metal is provided wherein the strip stock is formed cylindrically and passed through a rolling station wherein roll passes formed by small diameter rolls traverse the stock on the bias along helical paths which successively overlap so that a uniform and flat rolled surface is formed.

Abstract: An apparatus for working a surface of a metal pipe is provided. The apparatus comprises a drawing unit for drawing a metal pipe to reduce a diameter thereof, and a working assembly for working the diameter-reduced metal pipe to form an inner surface and/or an outer surface thereof into a predetermined configuration. The working assembly includes a rolling unit and a driving mechanism therefor. The rolling unit includes a housing, a plurality of rolling rolls rotatably disposed within the housing and outside the metal pipe so that the rolling rolls have their respective axes extending at an inclination angle with respect to an axis of the metal pipe. The rolling rolls are respectively mounted on support shafts rotatably supported in the housing through thrust bearings. The driving mechanism drivingly rotates the rolling unit to revolve the rolling rolls around the metal pipe. The rolling unit is removably mounted on the driving mechanism.

Abstract: For manufacturing tubes of the "corrugated" type, i.e. comprising at least one deformation of helicoidal profile, the smooth tube (28) is displaced axially inside a fixed sheath (7) about which rotates a sleeve (4) fixed to a head forming support for at least one radially mobile "corrugating" knurl; the displacement of the knurl is effected by a cam (25-26) which surrounds said head and which is actuated by a jack (13-14). Opposite this "corrugating" knurl there is provided a cutting knurl which cuts the tube at the end of the "corrugation" operation. The number of the "corrugating" knurls may vary.

Abstract: A method of reducing the thickness of the wall of a tube wherein in the zone of the reduction of the wall thickness, on the internal surface of the tube the plug of a mandrel exerts a pressure causing an increase of the inner diameter, and on the external surface rolls exert a pressure securing invariability of the outer diameter of the tube.A rolling mill for reducing the thickess of the wall of a tube comprises a extension plug (4) mounted on a mandrel (1) and working rolls (6) which in the zone of the reduction of the wall of the tube (2) have the surface of the roll face parallel to the axis of the tube (2). Bearings (7) of working rolls (6) are radially-slidably mounted in the planetary cage (8).

Abstract: A roll head for a planetary crossrolling mill in which the roll shaft bearing the tapered roll is mounted at one end close to the tapered roll in a radial bearing and an axial bearing while the other end rests with teeth in a rotationally engaged but axially movable manner in a hollow shaft of a bevel wheel driving the roll shaft.

Abstract: A skew rolling mill is equipped with a plurality of skew or inclined rollers each of which is constructed of a number of roller segments (1', 2) which are interconnected in a form-locking, force transmitting manner. These roller segments are so related to one another that different roller segments may be assembled to form a plurality of different skew rollers which differ from one another with regard to their calibration and purpose. Thus, different roller segments may have different structural features and they may be made of different materials. Such variability obviates the need for keeping complete sets of skew rollers in stock for each size or calibration.

Abstract: A method and apparatus for the manufacture of spirally fluted tubes and which comprises a rotatable die for receiving the tube longitudinally therethrough during the forming operation for controlling the outer diameter thereof, a clamping apparatus for engaging the outer periphery of the tube and mounted on a movable base member for pulling the tube through the die, forming tools carried by the die for selectively exerting pressure against the outer periphery of the tube during the longitudinal movement thereof, and a reciprocal forming tool chuck apparatus engagable with the forming tools for controlling the inwardly directed pressure thereof against the tube to produce variable depth spiral grooves therealong.

Abstract: The invention relates to a method of manufacturing solid metallic materials having a circular cross section by employing a rotary mill. A three or four roll cross-type rotary mill is employed, with cross and feed angle setting selected so as to meet specific conditions. The method permits efficient production of metallic materials without internal cracks or internal fracture initiated from porosity. In one version of the method the material being worked is rotated. In another version the material is not rotated and the roll housing is rotated around the former. Where the latter version is employed, it is possible to work the material as produced by a continuous casting machine and without cutting.

Abstract: A rolling mill plant has a planetary skew rolling mill and a reducing or sizing rolling line disposed at a short distance therebeyond for the purpose of manufacturing tubes. In order to avoid axial stressing of the work material between the planetary skew rolling mill and the reducing or sizing rolling line when the work material is simultaneously located in both of them, a tension and compression measuring device is disposed in the region of the reducing or sizing rolling line for the purpose of corresponding regulation of the latter's drive motor. A torque measuring device is disposed between the mounting of the mandrel rod of the planetary skew rolling mill in order to be able to detect torque stresses in the work material which are then eliminated in dependence upon the measured values of the torque measuring device by corresponding regulation of the rotational speed of the rolls and of the rotor of the planetary skew rolling mill.

Abstract: A skew-rolling mill for reducing solid or hollow cross-sections, in which a roll carrier and a first hollow shaft rotatably mounted therein and allowing passage of the rolled stock are supported rotatable independently of each other in a stand. The roll carrier comprises three driven conical working rolls inclined to the rolled stock axis and mounted circumferentially spaced at 120.degree. intervals and adjustable with respect to the rolled stock axis. The shafts carrying the working rolls, whose axes cross the rolled stock axis at short distances apart, are each drivably connected to an intermediate shaft by way of a respective bevel gear pair.

Abstract: The apparatus for changing the rolls (6) of a skew rolling mill comprises a roll-change carriage (14) movable along the direction of feed of material (10) being rolled. A carrier (11) is mounted on the carriage (14) and carries a plurality of roll-clamping devices (12). Locking means (19, 20) are provided for interlocking the rotor (2) carrying a plurality of roll heads (5) skew mounted thereon and the carrier (11) in a predetermined axially-aligned, spaced position for removing or replacing rolls by means of the clamping devices. In a preferred embodiment there are two carriers movable in alternate alignment with the rotor (2).

Abstract: A method of making a new high performance heat transfer tube for use in an evaporator of a refrigeration system is disclosed. According to this novel method, a grooved mandrel is placed inside an unformed tube and a tool arbor having a tool gang thereon is rolled over the external surface of the tube. The unformed tube is pressed against the mandrel to form at least one internal rib on the interior of the tube. Simultaneously, at least one external fin convolution is formed on the exterior of the tube. The external fin convolution has depressed sections above the internal rib where the tube is forced into the grooves of the mandrel to form the rib. A smooth roller-like disc on the tool arbor is rolled over the external surface of the tube after the initial formation of the external fin and internal rib. The resulting heat transfer tube has an exterior with a subsurface channel consisting of interconnected cavities and subsurface passages.