Abstract: A water-transporting line includes an integrated heater system for protection against frost and the appropriate connection, attachment and control elements. A self-heating water conduit segment is provided that has an integrated heating device, which device encloses the outer surface of the water conduit segment. The various segments may be connected mechanically and electrically using corresponding connecting elements.

Abstract: A highly practical tube body for a pressure transducer is provided which has excellent pressure resistance, corrosion resistance, and tensile strength; which can be manufactured at low cost in comparison with cases of using stainless steel; and which makes it possible to keep inside diameter precision high. In this tube body for a pressure transducer, the pressure applied to the interior is varied periodically, and a seal layer (2) is provided to the internal peripheral surface of a tube body (1) made of a fiber-reinforced resin composed of fibers wound in layers.

Abstract: The present invention describes a tubular scoop that may be utilized with various assemblies for sampling fluid in a pipeline. The scoop includes a bend with a bend radius that is from two to four times the diameter of the scoop. The scoop defines a scoop face that is parallel to an axis of the tubular of the scoop. The scoop is mounted with a threaded connection that seals around the tubular. An additional seal comprises a compression nut that allows orientation of the scoop within the pipeline whereupon the scoop orientation is fixed by tightening the compression nut.

Abstract: For a method for manufacturing a hollow shaft with at least one integral flange made of fiber composite, a plurality of intersecting windings of fiber material are applied onto a core. Moreover, the core has, for each flange, a radial spreader ring with an axial bearing surface. The windings are laid over an outer circumferential portion of the respective spreader ring and fixed. One or several inserts made of fiber material are inserted in the area of the spreader ring between the windings. The fixing of the wound fiber material is released, but is first still held on the spreader ring. Portions of the windings are then pulled off from the outer circumferential portion of the spreader ring and brought to rest on the axial bearing surface of the spreader ring in order to form a partial portion of a flange.

Abstract: An umbilicus is provided for use in an umbilicus-driven fluid processing system. The umbilicus includes an umbilicus body having enlarged first and second ends, with an intermediate section located therebetween. At least one fluid-transmitting lumen extends between the first and second ends. The umbilicus further includes first and second end fittings, each associated with one of the ends of the umbilicus body. Each end fitting defines an interior cavity having a flared portion, with at least a portion of one of the enlarged ends of the umbilicus body being seated within the flared portion. The enlarged ends of the umbilicus body may be formed using a heated die at least partially inserted into the fluid-transmitting lumen.

Abstract: A self-actuated linearly retractable and extendible hose for use in transporting fluids (liquids, gases, solid particles, and combinations of these) between a source location and an output location can be implemented as an extendible hose comprising a biasing means, a sealing layer, and a reinforced cover layer. The sealing layer forms a sealed conduit for transporting the fluids, and the reinforced cover layer on the outside provides radial and longitudinal strength for the sealing layer. The hose can be operated by increasing internal pressure within the hose relative to ambient pressure. When the hose is pressurized by a fluid source, the internal pressure of the hose overcomes the retracting force of the biasing means and the hose extends. When the fluid source is turned off or disconnected from the hose, internal pressure is reduced and the biasing means exerts a tension force on the hose causing the hose to retract.

Abstract: A steam diffusing apparatus may include a steam inlet tube having steam-dispersion openings adjacent a lower end thereof and a mass of filaments surrounding the plurality of steam dispersion openings. The steam diffusing apparatus may also include a retaining tube surrounding the mass of filaments, a housing surrounding the retaining tube and having outlet openings therein, and an upper end cap coupled to an upper end of the housing and having an opening therein receiving the steam inlet tube. A lower end cap may be coupled to a lower end of the housing.

Abstract: A method and apparatus for forming at least one external annular flange (48 or 49) adjacent one end of a fiber reinforced thermoplastic tube (10) in which the tube (10) is mounted on a mandrel (12) and a first end portion of the tube is clamped in a collar (13) having at least one internal annular cavity (18 or 19) for forming a flange, a second end portion of the tube in the region (R1, R2) of the cavity is heated to soften the thermoplastic, and an axial load (L) is applied to the end of the tube by a piston (24) causing the softened tube to flow into the cavity (18, 19) in the collar (13) to form a flange on the tube.

Abstract: A multifunctional energy saving and carbon reduction apparatus includes an outer pipe and a foam layer. The outer pipe includes an inlet and an outlet, and each of the inlet and outlet is connected to an outer-pipe connector, inside the outer pipe is formed an inner space in communication with the inlet and the outlet. The foam layer is stuffed in the inner space and formed with a plurality of orifices and contains small amount of natural radiation ore powder. The multifunctional energy saving and carbon reduction apparatus allows the reactants, such as liquid fuel and oxidizer or gaseous fuel and oxidizer, to come into direct contact with the radiation element layer, when the reactants flow through the energy saving and carbon reduction apparatus, so as to enhance combustion efficiency.

Abstract: A duct element for the exhaust system of a motor vehicle with an internal combustion engine, including at least one flexible duct part, preferably a bellows. The flexible duct part is embodied at least partially from a first type of steel with a Mo-content ?4% or ?6% and with a N-content from 0.3% to 0.6% or from 0.18% to 0.25%, preferably embodied from steel of the type 1.4565 or the type 1.4547. Furthermore a decoupling element is provided for motor vehicles with an internal combustion engine and a respective use of steel embodied with a Mo-content ?4% or ?6% and a N-content from 0.3% to 0.6% or from 0.18% to 0.25%, preferably steel of the type 1.4565 or 1.4547.

Abstract: A pipe element has a circumferential shoulder at one end. The shoulder has an outer diameter greater than the outer diameter of the pipe element. A groove is positioned adjacent to the shoulder. The groove has a floor surface with an outer diameter less than the outer diameter of the pipe element. A bead is positioned contiguous with the groove. The bead has an apex with an outer diameter greater than the outer diameter of the pipe element. A combination of roller tools is used to cold work pipe elements and impart a desired shape to the sidewall in one method of manufacture. In another method, a spin forming tool is revolved in an orbit of increasing diameter within the pipe element captured within a die.

Abstract: An article has a polymeric substrate and a coating system. The coating system includes a metallic plating and a polymeric coating atop the metallic plating. The metallic plating has a thickness of at least 0.05 mm.

Abstract: An assembly for production of a threaded connection, including a first and a second tubular component with an axis of revolution and each including at one of its ends at least one first threaded zone produced on an external or internal peripheral surface of the component depending on whether the threaded end is male or female in type, and capable of cooperating together on makeup, the ends finishing in a terminal surface. At least one of the threaded zones has, in longitudinal section passing through the axis, a profile that follows a continuous and concave portion of a curve over at least 10% of the length of engaged threads of the threaded zone.

Abstract: An air duct includes a hollow main body defining a through slot, an inlet member and an outlet member connected to opposite ends of the main body. The inlet member includes a top wall, a bottom wall, a first sidewall, and a second sidewall. The second sidewall slantingly extends forward and away from the first sidewall. A space communicating with the through slot is bounded by the top wall, the bottom wall, and the first and second sidewalls. The space has an inlet wider than the through slot. The outlet member is perpendicularly connected to the main body and defines an outlet communicating with the through slot.

Abstract: The invention relates to an air-flow channel (1) for a ventilation device of a motor vehicle. According to the invention, a sealing element (7) is arranged in a bonded manner on at least one pipe opening (6) of the air-flow channel (1), in the region of an opening edge (2), said sealing element (7) being able to be arranged in the region of the opening edge (2) of the pipe opening (6), or applied onto said air-flow channel (1), by means of a fusing process or a thermal welding method such that the melted material of the sealing element (7) becomes joined to the heated material of the air-flow channel (1). The invention additionally relates to a method for producing an air-flow channel (1) for a ventilation device of a motor vehicle.

Abstract: A fluid duct has a plastic body with a forward cylindrical portion having an outer periphery and a rear cylindrical portion having an outer periphery. The forward and rear cylindrical portions are at equal radial distances from a center line of the duct. A bead is formed on an outer periphery of the duct body intermediate the forward and rear portions. The bead has a radially outermost distance measured perpendicularly away from the outer periphery of the forward portion. This is defined as a first distance. A second distance is defined between a forward end of the duct body to a rearmost end of the bead. The ratio of the first distance to the second distance is between 0.200 and 0.270.

Abstract: A tubular component with an end section has a profile, wherein the profile comprises a plurality of holding elements axially offset in longitudinal direction of the end section. The holding elements comprise at least one first azimuthal contour region and at least one second azimuthal contour region, wherein the outer contour of a holding element in the first contour region at least in sections is lowered or raised relative to the second contour region and wherein the first contour regions of at least two holding elements are offset relative to each other in azimuthal direction.

Abstract: The present disclosure relates to a pipe element with a trimmed edge for welding onto a carrier, wherein the trimmed edge is cut from a base tube so that the pipe element can be arranged on the surface of the carrier and welded to it along the trimmed edge, wherein the trimmed edge has a first cam with which the pipe element can be placed on the surface of the carrier. It is further provided that the trimmed edge has at least one second cam with which it can be placed on the surface of the pipe element, so that an air gap remains between the surface of the carrier and the trimmed edge in a region lying between the first cam and the second cam.

Abstract: A pipe has a tubular body with a male end and a female end. The male end has an external surface with a first engagement groove. The female end has an internal surface with a second engagement groove, and an aperture extending from an outer surface of the tubular body to the second engagement groove. The female end receives the male end of another pipe such that the first engagement groove of the male end axially aligns with the second engagement groove of the female end to establish a spline engagement groove having a groove length, LG. A flexible spline is located in the spline engagement groove to lock the pipes together and establish a pipe assembly. The flexible spline has a spline length, LS, and LS?LG.

Abstract: A flexible hose having an inner tube member made from a thermoplastic elastomer material and an outer tube member made from a non-elastic polyester material. The inner tube member is secured to the outer tube member only at an inlet coupler and an outlet coupler. The inlet coupler is constructed to secure to a water supply provided from a conventional household water spigot. The outlet coupler incorporates a flow restrictor allowing the inner tube member to equalize in pressure with pressurized water received from the water supply. Pressurized water expands the elongated inner tube member longitudinally along a length of the inner tube member and laterally across a width of the inner tube member thereby substantially increasing the length of the hose to an expanded condition wherein the hose contracts to a substantially decreased length when there is a decrease in pressurized water.

Abstract: A flow directing apparatus for directing fluid flow includes a flow body defining a bore therethrough configured and adapted to direct fluid flowing therethrough. The bore includes an outlet and an opposed inlet with an enlargement, formed as a countersink and/or a chamfer using a suitable boring device. The enlargement is configured and adapted to reduce sensitivity to entrance-edge conditions for the bore.

Abstract: Substrate processing uniformity is improved in the surfaces of wafers and between the wafers. An inner tube for a substrate processing apparatus for forming a high-k film, includes: a gas exhaust outlet formed at a sidewall of the inner tube; and a gas injection hole located at position spaced outward from the sidewall of the inner tube, wherein a distance of an outer edge of a substrate accommodated in the inner tube and the gas exhaust outlet is greater than a distance between the outer edge of the substrate accommodated in the inner tube and the gas injection hole.

Abstract: A duct has: a first non-metallic member extending between a first end and a second end, at least at the first end having an outwardly-projecting flange portion; a metallic flange member having a sleeve extending between a first end and a second end and a flange extending outward from the sleeve and having a first face and a second face; and a second non-metallic member extending between a first end and a second end having an outwardly-projecting flange portion, the first non-metallic member flange portion mounted to the flange first face and the second non-metallic member flange portion mounted to the flange second face.

Abstract: Air guide for a fan cowling of a motor vehicle, the fan cowling being arranged downstream of a heat exchanger in a direction of airflow. The air guide includes an air guide body having a plurality of surfaces and an air passage opening arranged between adjacent surfaces of the air guide body, a guide surface which corresponds to the opening and configured to act on airflow through the air passage opening; and an end region which extends from the guide surface and which is spaced from and extends in a plane which is substantially parallel to a plane of the surface of the air guide body. The guide surface begins at a first edge of the air passage opening and the end region ends at the opposite edge of the opening, and the end region does not overlap with an adjacent surface that continues at the opposite edge of the air passage opening.

Abstract: A fluid handling assembly provides conduits that deliver fluids therethrough. The fluid conduits include pipes, having an inner annular layer (2) of CPVC material, an intermediate annular layer (3) of metallic material and an outer annular layer (4) of CPVC material. Pipes are joined using inserts (9) that are engaged in cemented relation with a coupling. The inserts are configured to resist deformation at relatively high pressures that reduces the risk of separation of the layers of the pipe due to fluid infiltration between such layers.

Abstract: Apparatuses are provided for reducing noise generation from a dead ended conduit in a gas turbine engine. In particular A scooped bellmouth is provided that comprises a bellmouth within a surface having an outer perimeter an inner perimeter and a ramp diverging from the surface at a first end, the ramp extending radially through the outer perimeter of the bellmouth at a second end. The ramp diverts an airflow away from the bellmouth thereby preventing the development of a low pressure area at the bellmouth without affecting the efficiency of the gas turbine engine.

Abstract: A container treatment machine with a tank and spaced-apart valve housings, wherein a pressure-resistant delivery pipe having a curved section is provided between the tank and each valve housing directly or via an intermediate flow regulator, the delivery pipe being composed, at least in its curved section, of a hard plastic which is pressure- and temperature-resistant, and is acid- and alkali-resistant and permissible for foodstuffs, in particular polytetrafluoroethylene (PTFE or Teflon).

Abstract: In a first embodiment, at a time of magnetic pulse welding, a stepped tube profile machining process axially bores a walled tube from an end inward to a transition depth to form a section with a reduced wall thickness and then axially bores the walled tube from the transition depth to a fall off depth, thereby forming a section with a maximized welding wall section. In a second embodiment, also at a time of magnetic pulse welding, a surface angle tube profile machining process axially bores at a surface angle a walled tube from an end to a bore length to form an angular welding wall thickness inward to a maximized wall section. For both embodiments, the bored surfaces are virgin with no pits, oil, residue, or oxidation thereon, thus making the machined walled tubes available for immediate magnetic pulse welding.

Abstract: An end fitting (300), flexible pipe (100), riser (203), and method of producing the same are disclosed. A method of venting gas from annuli (312, 319) of a flexible pipe is also disclosed. The end fitting includes a first vent flow fluid communication path (311) and a further vent flow fluid communication path (318). The end fitting is capable of enabling gas to be vented from a flexible pipe body with two annulus regions (312, 319).

Abstract: The invention relates to a composite hose, which is capable of being used without leakage, and which has a longer length and/or diameter than has been previously achievable. A composite hose comprises a tubular body of flexible material arranged between an inner and an outer helically wound wire. The hose further comprises an axial strengthening means adapted to reduce deformation of the tubular body when the tubular body is subjected to axial tension, the axial strengthening means being adapted to exert a radially inward force on at least part of the tubular body when axial strengthening means is subjected to axial tension. The hose can have length above 30 m and a diameter above 400 mm. A method of, and apparatus for, making the hose are also described, which involves the use of a non-metallic mandrel.

Abstract: Radial seal type threaded joints for steel pipes have still room for improvement in ensuring sealability in terms of the rigidity of the pin nose. Specifically, the outer circumferential surface of the nose of the pin has an outward convex curved shape, and the sealing surface of the box has a tapered shape; and the cross-sectional area of the pin at a seal point that is a portion on the outer circumferential surface of the nose of the pin, the portion first coming into contact with the sealing surface of the box when threaded-joined, is 35% or more of the cross-sectional area of an original pipe portion corresponding to an unprocessed portion.

Abstract: A blower pipe includes an inlet port, an outlet port, a flow path that connects the inlet port and the outlet port and is bent at least in one location, and plural flow control members that are provided in mutually different regions in a direction in which air in the flow path is caused to flow and that control the flow of the air, wherein a flow control member of the plural flow control members closest to the inlet port (a) cuts off a portion of a bent portion of the flow path while air crossing the portion, (b) makes an elongated gap to pass air, and (c) satisfies following condition; when a virtual straight line which passes through both end portions of the elongated gap is drawn, the virtual straight line lies downstream of an extension line of a wall immediately before the flow path is bent.

Abstract: A straw is provided for drinking beverages which may contain pieces, fragments, chunks, etc., of food matter. The straw has one or more notches, cuts or recesses located near an end portion which facilitates fluid intake even in the presence of blocking material.

Abstract: A connection arrangement comprising a tube element formed from a fiber composite material, the tube element has a conically shaped tube attachment area on one of its ends; a flange attachment area is provided on a flange element, the flange attachment area is inversely conically shaped to the tube element; the tube element and the conically shaped tube attachment area are integrally formed and the tube attachment area is glued to the flange attachment area.

Abstract: An exhaust tip assembly for an exhaust system of a vehicle includes an accent member and a collector member that is made substantially from a polymeric material. The collector member includes a collector portion and an attachment portion. The collector portion includes a first end and a second end. The collector portion defines a passage that extends from the first end to the second end. The first end is operable to receive a downstream end of a tailpipe, and the second end is operable to removably attach to the accent member. The attachment portion is configured to mount to a fascia member of a vehicle to thereby expose the accent member from the fascia member.

Abstract: A corrugate tube with a clamp integrally includes a straight tube portion and a bellows tube portion and a locking clamp is provided on the straight tube portion. The straight tube portion provided with the clamp is thicker than the bellows tube portion. A slit in a longitudinal direction of the tube is provided in an opposite direction of the clamp. A hole is provided communicating with the slit. A groove or a hole is provided on the straight tube portion. A radius d2 of a hill portion of the bellows tube portion is sufficiently larger than a radius d of a valley portion of the bellows tube portion, and a thickness T of the hill portion is gradually smaller as the bellows tube portion extends toward a tip. The bellows tube portions are arranged in between straight tube portions, and the clamps are provided on required straight tube portions.

Abstract: The present invention is a low point pipe fitting for draining accumulated condensation from electrical conduit systems that are installed in industrial, commercial and residential facilities. The fitting includes a centrally disposed engaging tool members with opposing threaded fittings with a drain incorporated in the underside of the engaging tool members.

Abstract: A reduced weight and repairable piston accumulator. The accumulator includes a load bearing metallic cylinder with removable end caps secured thereto with slip flanges for allowing repairability and for achieving the required cycle life. The cylinder serves as the surface on which the piston slides and is designed such that it sustains the axial stress induced by pressurization of the accumulator. A composite over wrapping is designed such that it sustains the stress in the hoop (radial) direction. A stress transitioning bushing can be provided for transitioning hoop stresses between the overwrap and the slip flange. When combined with the cylinder, the fibers of the composite wrap will not be placed in shear and thus will not fatigue in the same manner as some prior art designs.

Abstract: A network and method of laying network cables in water supply pipes is disclosed. A building is situated near a roadway along which is laid a trunk cable. A water supply pipe branches off the water main to enter the building. A water supply pipe is provided at the time of construction of the building and is an underground pipe. It is conventional to provide a dedicated (and usually underground) conduit for a branch cable, which is expensive and disruptive. In the present invention the branch cable is laid along water supply pipe, enabling the cable to cross between the trunk cable and the building with minimal disturbance of the ground therebetween. This is achieved by introducing cable to pipe by use of a suitable Y-junction at location and removing the cable from the pipe by use of a second such Y-junction at location.

Abstract: A downspout extension has a low-profile to direct rainwater away from a building. A transition adapter can be used to transition from a generally circular or square cross-section of a downspout to a low-profile cross-section of a corrugated duct of the extension. The extension can include internal supports to withstand being stepped on and can have a generally rectangular or trapezoidal cross-section with a longer width than height. The corrugated duct can also be comprised of integrated accordion corrugation sections and transverse non-collapsible ribs to give the corrugated duct extension greater flexibility. The extension can be connected to a downspout using a flexible elbow duct, a downspout connector, and a downspout adapter. The transition adapter of the extension can also be connected directly to a downspout.

Abstract: A device for suctioning a liquid contained in a vessel, that includes a take-up tube that is received in the vessel such that a bottom end of the section is submerged in the liquid. The bottom end of the take-up tube is extended downward by a rotationally symmetrical tip which has a main substantially vertical axis open downward and which includes an outer radial collar.

Abstract: An exhaust system includes an exhaust pipe. The exhaust pipe includes an outer pipe and an inner pipe. A first through-hole and a second through-hole are provided in a peripheral surface of the outer pipe and a peripheral surface of the inner pipe, respectively, to receive an exhaust gas detector. Third through-holes are provided in the peripheral surface of the outer pipe, at a different position than that of the first through-hole. Since the third through-holes are provided in the outer pipe, a liquid can be drained promptly from a space between the outer pipe and inner pipe. Exhaust gas can be prevented from being discharged to the atmosphere by sealing the third through-holes.

Abstract: A rotatable exhausting structure of a portable air conditioner has a housing and a connecting tube. The housing has through hole, and multiple holders and a resilient stop separately arranged around the through hole. The connecting tube has a flange formed on and around the an outer surface of the connecting tube and held between the holders and the resilient stop of the housing, and is used to be connected to an exhausting pipe. Thus, the connecting tube is rotatable relative to the housing. When torque is caused in the exhausting pipe due to redirecting it, the connecting tube rotates accordingly. The exhausting pipe is not bent or twisted and keeps in good condition.

Abstract: A low profile downspout extension is formed in multiple segments including a flexible conduit, a splash block and an extension. The splash block transitions from a circular inlet into a low profile pentagon configuration with a central bead along the top surface of the low profile body portion to define an apex of the pentagon shape. The body portion is wider than the diameter of the circular inlet but has a height at the central bead that is more than half the diameter of the circular inlet. The body portion has ribbed side walls to strengthen the splash block without requiring internal reinforcement. The bottom surface of the splash block defines a flow path that extends generally linearly from the bottom of the inlet opening to the bottom of the pentagon-shaped outlet. An open configuration for the splash block provides an alternative above-ground splash pad structure.

Abstract: Disclosed is a flexible plastic hose (1) comprising a tubular hose body (2) having web portions (7) and a helical reinforcing rib (8), and a cuff (3a) mounted to an extremity (16) of the hose body (2) comprising a moulded end fitting (5a) bonded to the extremity (16a), and a stress relief element (4) with a first segment (S1) having an internal screw-thread (15) complementary to the helical reinforcing rib (8). Disclosed is also a method for making same, and use of the hose (1) as a medical hose.

Abstract: A water supply fixture is used to connect water supply source to an electronic bidet toilet seat. The water supply fixture includes two main portions. The first portion is a decorative rigid assembly that can be designed to blend in with the electronic bidet toilet seat appearance. This first portion, when being installed with the electronic bidet toilet seat, will occupy the plain sight of the user's view when he or she is in the standing position and looking down to the bidet toilet seat. The second portion of the water supply fixture is a flexible supply hose which generally may not be aesthetically good-looking,. This unaesthetic flexible supply hose, when being used, will be partly covered by the first portion of the water supply fixture, largely hidden underneath the electronic bidet toilet seat, and almost completely out of the user's view when looking down to the bidet toilet seat.

Abstract: Provided are a connection structure for connecting corrugated synthetic resin pipes and a corrugated synthetic resin pipe used in the connection structure. The pipe is lightweight, low cost, and simply structured with a small number of components, having sufficient resistance to water and pressure, and excellent sealing performance without the use of robust material or requiring high precision, and capable of being easily connected and manufactured. A first corrugated synthetic resin pipe 1A is provided at an end 10 with a cylindrical insert end 3 formed by adhering a synthetic resin layer 5 to the outer surface of the end 10 so as to fill at least corrugated recesses 2a. A second corrugated synthetic resin pipe 1B is provided at an end 11 with a socket 4 formed by adhering synthetic resin to the outer surface of the end 11 and cylindrically extending the resin outwardly in the axial direction.

Abstract: Drill pipe segments, communication systems, and methods of manufacturing pipe segments usable for communicating data wirelessly between sensors and tools placed in an oil and/or gas well are provided. Communication specks are applied on at least one of an outer surface or an inner surface of the pipe segments or coil tubing.

Abstract: A tubular fluid conduit which is especially adapted for use in supplying pre-conditioned air to an aircraft being serviced, wherein the tubular conduit may be fabricated as a thermoplastic extrusion having a constant diameter dimension, whereby a first end portion may be fluidically connected to a large diameter supply conduit while a second end portion may be fluidically connected to a small diameter use conduit as a result of spiral wrapping the second end portion around the use conduit. Alternatively, the tubular conduit may be fabricated as a thermoplastic extrusion having repetitive sections with each section comprising relatively large diameter and relatively small diameter portions.

Abstract: A vibration-resistant reinforced concrete watertight pipe, at opposite ends of which coupling units formed of a separate material are formed, and a method of manufacturing the same are provided. The vibration-resistant reinforced concrete watertight pipe includes a reinforced concrete pipe having a reinforcement mat, which is assembled with longitudinal reinforcements and transverse reinforcements, disposed in a concrete layer, and a convexity coupling part and a concavity coupling part that are coupled to opposite ends of the reinforced concrete pipe and have coupling ridges and coupling furrows respectively. Here, the coupling part and the concavity coupling part are formed of a synthetic resin, which is different in physical properties from the reinforced concrete pipe, and have the same shape and thickness as the reinforced concrete pipe. Each of the convexity coupling part and the concavity coupling part has a metal core installed therein to increase a coupling strength.