Abstract: A heat insulating noise reducing duct includes: an internal layer formed by helically winding a flat fibrous band and integrally bonding outer circumferential faces of adjacent joint parts of the band by resin reinforcing bands to thereby form a substantially smooth cylindrical shape; one or more resin linear bodies helically wound between these adjoining resin reinforcing bands and bonded to the fibrous band; an open-cell foam layer formed by helically winding an open-cell foam resin band onto an outer circumferential face of the inner layer while making its paired side edges abut each other; an intermediate sheet layer formed by helically winding a thin resin sheet-like band onto an outer circumferential face of the open-cell foam band while partially overlapping the resin sheet-like band, and by integrally bonding the overlapped parts; a closed-cell foam layer formed by helically winding a closed-cell foam resin band onto an outer circumferential face of the sheet layer while making its paired side edges a

Abstract: A hose has an inner wall 1 of blow moulded tube and an outer wall 2 of continuous, spirally formed, corrugated tube. At each end of the hose, the inner wall extends further than the outer wall. The walls are separated by a rigid spacer 3 inserted into the end of the outer tube. The walls are united to a moulded connection member 4. This arrangement has a relatively long spigot 5 which extends from a cavity 6. The inner wall is slid onto the spigot as far as the bottom 8 of the cavity. A radially parting mould is placed around the connection member at a nose 9, within which the cavity extends. The mould has an aperture for the outer wall. On injection of material into the mould, the moulding 7 is formed in the cavity 6, along the extent of the inner wall on the spigot 5 as far as the spacer 3 and past the end 10 of this along an end portion 11 of the outer wall. The mould forms the outer diameter of the moulding to the dimension of the nose 9 and limits it from extending along the outside of the outer wall.

Abstract: A pipe formed from a continuous, cold rolled, lock seam quality, sheet steel, having a spiral rib. The pipe may be protected by an abrasion or corrosion resistant coating. The pipe is normally used for storm drains, culverts, sewer lines or HVAC. A closed spiral rib formed in the pipe wall adds strength to the wall, while maintaining a smooth inner wall that promotes exceptionally good fluid flow. The pipe has a smooth interior surface with outwardly projecting structural ribs of helical configuration throughout the length of the pipe.

Abstract: An object of the present invention is to efficiently absorb the energy of an external force applied to a vehicle body without an appreciable increase in weight of an automobile. To achieve the object, the present invention provides an impact energy absorber made of a composite in which kraft paper is placed on the outside and inside of a metal sheet such as iron foil or hard aluminum foil. The impact energy absorber is a flexible pipe having a substantially quadrangular cross section and provided with spiral-shaped concaves and convexes on the outside and inside of hard aluminum foil. The energy absorber is bonded to the room-side surface of an outer panel of the vehicle body using an adhesive. When an external force is applied to the energy absorber, the energy absorber can absorb the energy of the external force by being deformed plastically.

Abstract: The invention has mainly as its object a metal tubular tube (1) comprising hollow compartments (7), and a flexible tubular conduit comprising at least one such tube. The tube according to the invention is characterized by the fact that it comprises at least one hollow channel (7) formed by walls belonging to a strip and spirally wound around an axis (6) of tube (1). The invention applies mainly to the production of flexible tubular conduits for transporting hydrocarbons.

Abstract: A plastic profiled strip (10) is provided for producing helically wound tubes or pipes, the strip (10) having female and male joint formations (13, 14) extending along opposite longitudinal margins thereof and arranged so that upon spirally winding the strip into a tubular form, the joint formations (13, 14) can be interlocked to thereby lock adjacent windings of the strip together, the male joint formation (14) comprising a hinged flap (15) which is flexibly connected to the strip (10) for hinging movement between a disengaged or unlocked position displaced from the plane of the strip (10) and a locking position wherein it interlocks with the female joint formation (13) of an adjacent winding of the strip (10).

Abstract: Heat-reflective and protective sleeving is provided which has both an interior and an exterior convoluted profile. The sleeving includes layers of polymeric material, insulative material and reflective material which is assembled together into the convoluted profiles. A method and apparatus are provided for manufacturing the convoluted sleeving by wrapping a fabric-backed foil over a convoluted polymeric tubing while pushing the laminate into the grooves and over the crests of the convoluted profile of the polymeric tubing. In the preferred arrangement which is shown, this procedure is facilitated by the use of a plurality of worm gears that rotate substantially in unison in order to pull the convoluted polymeric tubing through an area defined by the worm gears, while simultaneously forming the convolutions in the laminate at the same time that the laminate is engaged with the external convoluted surface of the polymeric tubing.

Abstract: A high pressure subsea pipe, particularly for underwater use, has the ability to flex while being transported and installed. The pipe has a friction reinforcement structure made of overlapping layers increasing substantially the capacity of the pipe in longitudinal direction. The reinforcement layer may be a helical wrap, either cylindrical or conical, or conical sleeves nested within one another. An articulated carcass has turns of a helically wrapped main and ancillary wires, offering no axial slack in either tension or compression or in both directions while remaining flexible.

Abstract: Thermally insulating pipe lagging comprising a tube of compact and flexible elastomer type material designed to come into contact with the pipe to be insulated and shaped on its inside surface to have a helical groove which provides between its adjacent turns a coil filled with air or gas when the lagging is put into place so as to surround said pipe.

Abstract: A mobile vehicular antenna for use in accessing stationary geosynchronous and/or geostable satellites. A multi-turn quadrifilar helix antenna is fed in phase rotation at its base and is provided with a pitch and/or diameter adjustment for the helix elements, causing beam scanning in the elevation plane while remaining relatively omni-directional in azimuth. The antenna diameter and helical pitch are optimized to reduce the frequency scanning effect. A technique is provided for aiming the antenna to compensate for any remaining frequency scanning effect.

Abstract: A surgical cutting instrument having an elongated rotatable inner member provided with a cutting edge at its distal tip, the inner member adapted to rotate within an elongated outer tube having a window adjacent its distal end adapted to cooperate with the cutting edge of the inner member. The outer tube is provided with a portion thereof adjacent its distal end which enables the distal tip of the outer tube to be bent at an angle relative to the proximal portion of the outer tube. The outer tube may be bent by a user into a selected angular position with the aid of a tool calibrated in a plurality of discrete positions. The tool is adapted to enable the outer tube to be rotated to any selected position prior to being bent so that the window at the distal tip of the outer tube may be caused to face in any desired direction relative to the bend in the outer tube.

Abstract: A hose with reinforcing threads, includes an inner wall forming a pipe wall; a plurality of coated conductive wires spirally wound with a predetermined pitch; a plurality of reinforcing threads disposed on outer surfaces of the inner wall and the coated conductive wires along a pipe axis direction with a suitable interval in a circumferential direction; and an outer wall formed at an outside of the reinforcing threads. The outer portions over the coated conductive wires protrud outward so that the outer surface of the hose is spirally corrugated. The outer wall is formed of a plurality of synthetic resin band materials spirally wound for every pitch of the coated conductive wires.

Abstract: This invention relates to a flexible metal pipe covered with an impermeable sheath of a shrinkable, preferably semicrystalline polymer or polymers, characterized in that it incorporates between the shrinkable polymer sheath and the metal pipe an intermediate elastomer layer (8), optionally vulcanized or reticulated, and/or a TPE in the form of a continuous tubular sleeve (FIG. 3) or of a tape (FIG. 4 to 6). Sheathed pipes of this type are particularly suitable for flexible pipelines, optionally with suitable supports, for carrying oil and gas.

Abstract: A flexible hose assembly for conveying gas comprising an inner tube member having a reinforcing spring coil that selectively functions as an electric heater engaging the inner surface and an outer flexible tube member having its head and outlet ends closed upon those of the inner member. A second reinforcing spring coil surrounds the outer surface of the outer member such that a dead air space or insulating chamber is formed between the two flexible tubes. Superior insulation, flexibility, energy consumption, weight and strength characteristics are achieved. A temperature responsive electrical device can be mounted near the outlet end of the inside wall of the inner tube with leads extending through the hose exiting the head end for connection to a controller for controlling an external heating or cooling system or for controlling electric power applied to the inner spring coil for directly heating the flowing gas for delivering temperature controlled heated gas to the end user system.

Abstract: A pressure-resistant helical corrugated pipe comprises a helical corrugated pipe wall formed by a top portion, opposite side wall portions and a bottom portion; and a continuous thin metal belt plate disposed at least in the top portion or the bottom portion and also in part or the whole of the opposite side wall portions. The metal belt plate serves as a constitent element for the pipe wall. A portion of the metal belt plate disposed at the top portion or the bottom portion has one or more reinforcement ribs and a connective portion for the metal belt plate is integrally formed of a synthetic resin material or rubber material.

Abstract: A tubular supporting element for supporting an elastic sleeve for covering a junction of cables which is provided with a wall which has a groove or incision directed according to a helical line and which has a radial depth from the outer surface of the supporting element less than the radial thickness of the supporting element. The incision has a mouth at the outer surface of the supporting element with a width of less than 0.1 mm, preferably less than 0.05 mm, so as to provide a strip between the incision having a substantially rectangular cross-section. Also, a process and an apparatus for making the tubular supporting element.

Abstract: A cleaner hose includes a hose body, connection cylinders to be connected to a cleaner operating pipe and a cleaner body, respectively, which are connected to ends of the hose body, respectively, and a reinforcement wire material wound in the hose body spirally and continuously over the whole length of hose body. The reinforcement wire material is shaped like a steeply slanted spiral in a predetermined length portion near one of or both of the ends of the hose body so that adjacent spiral portions of the reinforcement wire material are close to each other while a hose wall of the hose body is loosened toward the inner circumferential surface. On the other hand, the reinforcement wire material is shaped like a gently slanted spiral in an intermediate portion except the one of or both of the ends of the hose body so that adjacent spiral portions of the reinforcement wire material are separated from each other in the direction of a pipe axis.

Abstract: A bending device includes a bellows with an internal space, an operating wire for bending the bellows, and multiple pairs of independent limitation structures for limiting an axial compression of the bellows. The bellows includes a corrugated peripheral wall defined by first portions that bulge radially outward and are arranged alternately with second portions that bulge radially inward. The peripheral wall has first and second regions, each of which includes a predetermined number of alternating first and second portions. A pair of limitation structures are mounted on diametrically-opposite sections of each of the first regions and on diametrically-opposite sections of each of the second regions. The sections of each first region are spaced from each other in a first direction while the sections of each second region are spaced from each other in a second direction.

Abstract: Insulated flexible metal piping is provided which includes a metal piping section having inner and outer windings comprising metal bands which are spiral-wound in overlying relation with their leading and trailing edges forming a spiral, interlocked seam. The flexible metal piping section is slidably inserted in an insulating sleeve, which can comprise a plastic material for enclosing the metal piping section. A method of forming the insulated metal piping is disclosed which includes the steps of providing inner and outer spiral windings; interlocking the leading and trailing edges thereof; and slidably inserting a flexible metal piping section formed thereby in an insulating sleeve. Further disclosed is an application of the insulated metal piping in a flue system.

Abstract: The invention discloses a wire wrapped composite spiral hose, having a plurality of layers of fabric wrapped around a preformed convolute hose and held in place by a continuous wire spaced within the convolutions. A method and device for preparing the hose is disclosed using parallel elongate mandrels which are synchronized to rotate and apply the wire spaced in the convolutions.

Abstract: A flexible conduit for the exhaust line of an internal combustion engine includes a flexurally supple tube having several helical corrugations of equal pitch and a flexible supporting coil spring having its ends fixedly connected to flanges at opposite ends of the tube and which is frictionally received in the trough of one of the helical corrugations.

Abstract: A multi-layer tube suitable for use on motor vehicles composed of a cylindrical wall having an outer surface, and an inner surface essentially parallel to the outer surface. The cylindrical wall has a first region having an essentially uniform cross-sectional diameter and a second region which has a cross-sectional diameter differing from the essentially uniform cross-sectional diameter of the first region. The second region has at least one convolution or corrugation contiguously adjacent to the cylindrical wall of the first region.

Abstract: A flexible hose construction and method of making the same are provided, the flexible hose construction comprising an inner corrugated hose made of polymeric material and having a plurality of outwardly convex projections with recesses therebetween and extending from one end thereof to the other end thereof, an outer sleeve of reinforcing material disposed in telescoping relation on the inner hose, and a tube of polymeric material disposed between the sleeve of reinforcing material and the inner hose and extending in a generally straight-line manner from projection to projection of the inner hose so as to tend to prevent the sleeve of reinforcing material from entering into the recesses of the inner hose an amount that would tend to substantially reduce the flexibility characteristics of the inner hose.

Abstract: A hydraulically efficient metal pipe particularly adapted for use in storm drain and sanitary sewer applications which is adapted for use with a self-supporting interior inert protective lining. The pipe has a channeled wall defining a plurality of outwardly projecting structural ribs and a hydraulically smooth interior surface. The ribs are preferably of a helical configuration and the channels which are formed interiorly thereof are generally either square or rectangular in cross-section and are open along the interior surface of the pipe. The walls defining the ribs can be tapered inwardly to form triangular-shaped channels so as to define an anchor throughout the length of the pipe for securing thereto a smooth interior lining of corrosion-resistant protective material.

Abstract: A bending device for use in an endoscope, a catheter or the like is of a simple construction having a coil, an operating wire and a pair of limitation members for limiting an axial compression of the coil. The pair of limitation members are arranged along the length of the coil, and are mounted respectively on diametrically-opposite portions of the coil. The coil is bendable in a direction perpendicular to a plane in which the pair of limitation members are disposed. Instead of the coil, a bellows can be used.

Abstract: A hose for low pressure and vacuum applications is provided by a helically wound strip of resilient material. The leading and trailing posts of the helically wound strip interlock with one another and are provided with projections which define a space for confining a bead of bonding material. The profile of the hose configuration prevents the bonding material from encroaching areas of flexation in the hose. The helically wound hose has a close pitch and exhibits good hoop strength, flexibility and bonding characteristics.

Abstract: A cleaner hose with a built-in current conduction wire includes a reinforcing wire rod for holding strength and a conductive wire for current conduction, which are spirally wound in the inside of a hose body, and further includes a coated wire constituted by the reinforcing wire rod and the conductive wire built in the hose. The reinforcing wire rod and the conductive wire are separated at an interval and are integrally coated with a synthetic resin raw material at an interval. A coating portion of the reinforcing wire rod and a coating portion of the conductive wire are connected to each other through a thin connection portion which can be torn off, and only the coating portion of the reinforcing wire rod is connected through an adhesive to an inner surface of the hose body.

Abstract: A fluid conveying hose, especially a refrigerant conveying hose, that exhibits improved resistance to permeation of the refrigerant while still affording desirable flexibility, and a fitting for such hose and methods of making the hose and the union between the hose and fitting. Also provided is a coupling assembly for a hose and a service fitting that is a considerably less expensive alternative to existing assemblies equipped with relatively expensive shut-off valves or quick connect/disconnect couplers.

Abstract: A double wall vent pipe is provided which comprises a first tubular wall that is helically corrugated to form radially outermost ridges spiraled around the outside of the first tubular wall and corresponding first recesses spiraled between the outermost ridges. The vent pipe also comprises a second tubular wall slidably disposed in a concentric relationship with the first tubular wall. The second tubular wall is helically corrugated to form radially innermost ridges which spiral around the inside of the second tubular wall and corresponding second recesses spiral between the innermost ridges. The radially innermost ridges are oriented in a direction oblique to the orientation of the radially outermost ridges such that a space between the first wall and the second wall will be maintained within the first recesses and the second recesses regardless of any bending of the vent pipe.

Abstract: A pressure-withstanding synthetic resin pipe includes an inner wall of a synthetic resin and an outer wall of a synthetic resin. A metallic reinforcement belt plate having an inverted U-shaped sectional contour and a flat, metallic belt plate having ends bent to form engagement portions and adapted to be engaged with open end portions of the metallic reinforcement belt plate are disposed between the inner wall and a protruded corrugation portion of the outer wall.

Abstract: A pressure-resistant helical corrugated pipe comprises a helical corrugated pipe wall formed by a top portion, opposite side wall portions and a bottom portion; a wide metal belt plate of a thin metal plate disposed at least at the top portion and the opposite side wall portions; and a small width metal belt plate being separate from the wide metal belt plate and disposed at the top portion of the pipe wall in overlapping relation to the wide metal belt plate in the direction of the thickness of the pipe wall. The two metal belt plates are integrally connected together at an overlap portion by a synthetic resin material or a rubber material.

Abstract: A flexible hose construction and method of making the same are provided, the flexible hose construction comprising an inner corrugated hose made of polymeric material and having a plurality of outwardly convex projections with recesses therebetween and extending from one end thereof to the other end thereof, an outer sleeve of reinforcing material disposed in telescoping relation on the inner hose, and a tube of polymeric material disposed between the sleeve of reinforcing material and the inner hose and extending in a generally straight-line manner from projection to projection of the inner hose so as to tend to prevent the sleeve of reinforcing material from entering into the recesses of the inner hose an amount that would tend to substantially reduce the flexibility characteristics of the inner hose.

Abstract: The present invention provides an insulated breathing tube arrangement to prevent heat loss from the inhalant gas in a recirculatory aided breathing circuit thereby reducing internal vapor condensation commonly associated with such breathing circuits while also stabilizing the relative temperature and humidity within such breathing circuits. The insulated breathing tube arrangement includes a thin flexible partially longitudinally compressed casing surrounding a thicker corrugated tube. The thin casing allows for hairpin bending of the breathing tube arrangement and provides an insulating dead air space around the corrugated tube. In another arrangement selected enlarged corrugations are provided in spaced relation along the corrugated tube to engage the inner surface of the casing in a preselected spaced arrangement with respect to said corrugated tube to compartmentalize insulating dead air spaces between the tube and the casing.

Abstract: Joint formers for coupling between duct components having different cross-sections include a core having holes for fixing members and an opening provided with a hollowed out recess. In the opening there is formed at least one series of stepped spot-faced edges forming a series of cavities, each cavity rotated with respect to the others.

Abstract: A bending device for use in an endoscope, a catheter or the like is of a simple construction having a coil, an operating wire and a pair of limitation members for limiting an axial compression of the coil. The pair of limitation members are arranged along the length of the coil, and are mounted respectively on diametrically-opposite portions of the coil. The coil is bendable in a direction perpendicular to a plane in which the pair of limitation members are disposed. Instead of the coil, a bellows can be used.

Abstract: A rigid polyvinyl chloride pipe comprises a strip member A that comprises a rigid polyvinyl chloride strip 1 with a U-shaped cross section consisting of an intermediate portion 1a of a predetermined width having a generally flat surface on at least one lateral side and two ribs 1b that extend from opposite sides of the intermediate portion 1a in a generally perpendicular direction with respect to the intermediate portion, with a layer of flexible synthetic resin 2 highly fusible to the rigid polyvinyl chloride resin being fused integrally to substantially the entire outer surface of the lateral side of both ribs 1b.

Abstract: A hose continuous in series throughout an entire length integrally formed with a water-intake port, L-shaped bending part, an intermediate part and a drain port in this order from one end of the hose to the other. The substantially general part of the intermediate part is formed with corrugations having inclined side walls of unequal length which are constructed so that shorter inclined walls can be easily brought into their contracted positions substantially parallel to the longer inclined walls and they can self hold their positions. The hose has such a length that the substantially whole length thereof can be housed in an outer casing of a washing machine in its contracted state.

Abstract: A flexible conduit for vehicle engine coolant circuits, which conduit comprises a series of at least a first relatively rigid portion and a second relatively deformable bellows portion capable of being deformed at least into a curved portion; and an inner and outer wall made of different plastic materials.

Abstract: A pressure-resistant helical corrugated pipe comprises a helical corrugated pipe wall; and two kinds of thin metal belt plates provided as a pipe wall-constituting element. The metal belt plates are disposed at least partially in overlapping relation in the direction of the thickness of the pipe wall. The overlapped portions of the metal belt plates are spaced from and held out of contact with each other by an intermediate resin layer, and the overlapped portions are integrally connected together by the intermediate resin layer.

Abstract: A multi-layer tube suitable for use on motor vehicles composed of a cylindrical wall having an outer surface, and an inner surface essentially parallel to the outer surface. The cylindrical wall has a first region having an essentially uniform cross-sectional diameter and a second region which has a cross-sectional diameter differing from the essentially uniform cross-sectional diameter of the first region. The second region has at least one convolution contiguously adjacent to the cylindrical wall of the first region.

Abstract: A flexible hose construction and method of making the same are provided, the flexible hose construction comprising an inner tube made of polymeric material, an outer sleeve of reinforcing material disposed in telescoping relation on the inner tube from one end thereof to the other end thereof, rib structure disposed between the sleeve of reinforcing material and the inner tube, the rib structure being disposed on the inner tube so as to define alternating coil structure of rib structure and coil structure of non-rib structure serially along the longitudinal axis of the inner tube in a like repeating pattern thereof, the coil structure of non-rib structure comprise coil structure of void space, and an outer tube of polymeric material disposed between the rib structure and the sleeve of reinforcing material so as to extend in a generally straight-line manner from coil structure of the rib structure to coil structure of the rib structure so as to tend to prevent the sleeve of reinforcing material from entering i

Abstract: A flexible hose construction and method of making the same are provided, the flexible hose construction comprising an inner corrugated hose made of polymeric material and having a plurality of outwardly convex projections with recesses therebetween and extending from one end thereof to the other end thereof, an outer sleeve of reinforcing material disposed in telescoping relation on the inner hose, and stiff polymeric material disposed between the sleeve of reinforcing material and the inner corrugated hose and having an outer peripheral surface arrangement that is substantially straight-line smooth and continuous between each pair of adjacent projections and substantially coplanar with the apexes of the projections and having an inner peripheral surface arrangement that substantially mates with and is disposed in engagement with the projections and the recesses from the one end to the other end of the inner corrugated hose.

Abstract: The present invention relates to a plastic abrasion resistant protective sleeve for covering a radiator hose. The sleeve of the invention has an annularly corrugated external surface comprising a plurality of projections and troughs formed in said sleeve. The projections are substantially evenly distributed and have a substantially uniform size. The sleeve has a slit along its longitudinal axis which provides for easy application to or removal from the hose, and is made of plastic that is substantially unaffected by high temperatures. A method of using said protective sleeve for protecting a radiator hose from abrasion also is provided.

Abstract: A heat reshapeable rigid conduit and method for forming an elbow or offset having any desired bend radius therefrom. The rigid conduit is formed of a flexible metal tubing with a layer of heat softenable plastic preferably covering the exterior surface thereof. The conduit may be heated using conventional electric heaters on the job site, then shaped into the desired bend radius to form an elbow or offset. The plastic layer provides rigidity to the elbow or offset upon cooling. The flexible metal tubing has interlocking overlapping joined edges that permit flexing of the tubing when the plastic layer is heat softened. The flexible metal tubing resists the sawing action of a pulling line during the installation of an electrical conductor in the conduit. The plastic outer layer permits quick and inexpensive coupling between adjacent conduit sections.

Abstract: Flexible piping includes a first, spiral-wound band forming an inner winding and a second, spiral-wound band forming an outer winding in covering relationship over the inner winding. Inner and outer spiral-wound bands of insulating material are wound between the inner and outer windings and over the outer winding respectively. An insulating sleeve receives the spiral-wound inner and outer windings and the inner and outer insulating material bands. A method and a machine for forming the flexible piping are also disclosed.

Abstract: A pressure-resistant helical corrugated pipe comprises a helical corrugated pipe wall having a top portion, opposite side wall portions and a bottom portion; a continuous thin metal belt plate of a generally U-shaped transverse cross-section which is disposed in one of the top portion and the bottom portion and also in at least part of the opposite side wall portions extending from the one of the top portion and the bottom portion; another metal belt plate of a flat configuration being disposed in the other of the top portion and the bottom portion and disposed out of contact with the thin metal belt plate; and connective belt regions provided between the two metal belt plates in which the metal belt plates are absent, the connective belt regions being made of a synthetic resin or rubber to interconnect the two metal belt plates.

Abstract: A pressure-resistant helical corrugated pipe comprises a helical corrugated pipe wall having a top portion, opposite side wall portions extending from the top portion and a bottom portion extending from the side wall portions and disposed closed to the axis of the pipe; and belt plates which are formed separately from each other and made of a thin metal. The belt plates are disposed respectively at the side of the top portion and the side of the bottom portion as constituent elements for the pipe wall. The opposite edges of the two metal belt plates are disposed in abutted relation or in spaced opposed relation at the opposite side wall portions. The two metal belt plates are interconnected by connective portions which are made of a synthetic resin or rubber.

Abstract: A pressure-resistant helically corrugated pipe includes an integral, pipe wall corrugation helically wound to form a pipe, the corrugation having a trough portion disposed close to the axis of the pipe and outwardly projecting flange portions on opposite sides of the trough portion, adjacent flange portions being connected together to form the pipe having a helical outwardly projecting portion adjacent the trough portion. The pipe further includes a metal belt plate reinforcing member disposed within the trough portion of the helically disposed corrugation, the metal belt plate being generally U-shaped in cross-section so as to define a base, legs and free ends and opening toward the exterior of the pipe.

Abstract: A method and apparatus for preventing casing damage due to high axial loading in a well as a result of compaction of the surrounding earth formations. The method consists of providing specially sized and located grooves on both the inside and outside diameters of a section of well casing. The grooves are designed and spacers may be used in some grooves to ensure symmetrical deformation of the casing when subjected to a compressive loading.

Abstract: Strengthening the core of an insulated flexible duct formed of a helical wire wrapped with a flexible material with reinforcing tape. Strengthening tape is applied to the surface of the duct along its entire length. The apparatus for applying the strengthening tape is a tray having adjustable wiping arms. The wiping arms stretch the duct out as it is pulled through the tray. A roll of tape is mounted adjacent to the wiper arms and is automatically applied as the duct is pulled along the tray through the wiper arms. At least two wiper arms and continuous strips of tape along the longitudinal surface of the duct core are preferred.