JP2006064173A - Corrugated composite tube - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a corrugated composite tube capable of providing a sealing performance equal to that of a ring pipe by the form of a corrugated pipe and connectable without requiring complicated operations. <P>SOLUTION: In this corrugated composite tube, an inner tube 2 is formed by spirally winding a band-like synthetic resin, synthetic resin hollow projected lines 3 are spirally wound, at prescribed pitches, on the body part outer wall of the inner tube 2 with the projected lines facing outward. The projected lines 3 are reinforced by a metal projected line reinforcing material 10. A second band-like synthetic resin is spirally wound to cover the top parts 3a of the projected lines 3 to form an outer tube 5. Also, an outer tube reinforcing material 11 retaining the shape of the body part outer wall of the outer tube 5 in a smooth state is installed in the state of being installed across the adjacent top parts 3a and the top parts 3a of the projected lines 3. <P>COPYRIGHT: (C)2006,JPO&NCIPI

Description

  The present invention mainly relates to a corrugated composite pipe that is buried in the ground and is used as a water and sewage pipe or a communication or energizing cable in the pipe.

  Conventionally, as underground pipes, ring pipes in which crests and troughs are alternately formed in the pipe axis direction and corrugated in a ring shape (bellows shape), and corrugation spirals from one end of the pipe to the other end Corrugated pipes that are continuous in a shape are known.

  Since the ring part of the ring pipe is independent in the tube axis direction, when the ring pipes are connected to each other via a joint, it is possible to easily shut off the water supply by attaching a ring packing to the wave trough. Excellent water-stopping property. However, since the wave part in the ring pipe is formed integrally with the pipe, it is practically impossible to increase the rigidity by embedding a reinforcing material in the wave part, so an excessive earth pressure acts. Not suitable for the environment.

  On the other hand, since the corrugated pipe has undergone a manufacturing process in which a strip-shaped synthetic resin is formed into a pipe while being spirally fed out, it is relatively easy to incorporate, for example, a strip-shaped metal reinforcement in the manufacturing process. A metal reinforcing material embedded in a spiral wave portion can withstand excessive earth pressure.

  For example, in the corrugated pipe 70 shown in FIG. 14, a ridge 72 is spirally corrugated on the outer peripheral surface of the inner tube 71 forming the tube body, and the tops 72a of the ridge 72 are communicated with each other. An outer tube 73 is formed.

At this time, a reinforcing material 74 obtained by processing a metal thin plate into a convex shape is embedded in the ridge 72 and its skirt, and the pressure-resistant flat strength of the corrugated pipe 70 is enhanced by this reinforcing material 74 (for example, patents). Reference 1).
Japanese Patent No. 3165882 (page (2), FIG. 8)

  However, the corrugated pipe 70 described above is superior in pressure-resistant flattening strength as compared with the ring pipe, but has a disadvantage that the joint structure becomes complicated as compared with the ring pipe when the pipes are connected.

  Specifically, as shown in FIG. 15, the trough 75 of the corrugated pipe 70 is a water supply that spirally communicates from one end of the pipe to the other end, and therefore, usually a water stop block 76 is attached to the trough 75. Further, a water-stopping caulking material 77 is further provided so as not to generate a gap between the water-stop block 76 and the trough 75, and the water supply generated in the A part and the B part must be shut off.

  Moreover, in order to enhance the water stop effect by arranging the water stop block 76 near the connection side end of the corrugated pipe 70, the connection side end of the corrugated pipe 70 is formed in a zigzag shape as shown in FIG. It must be cut (see the cutting line 78 in the figure), and the connection work is complicated. In the figure, reference numeral 79 denotes a half joint that is wound around the connecting portion of the corrugated pipe 70 facing each other.

  Further, in the corrugated pipe 70 shown in FIG. 14, the portions of the outer pipe 73 that are installed on the protrusions 72 are curved by so-called “sinks” and do not become flat, so that a gap is formed between the half joint 79. There is also a problem.

  The present invention has been made in consideration of the problems in the conventional corrugated pipe as described above, and although it is a corrugated pipe, it can obtain a water stoppage performance equivalent to that of a ring pipe, and requires complicated work. The present invention provides a corrugated composite pipe that can be connected to each other.

  In the present invention, a belt-shaped synthetic resin is spirally wound to form an inner tube, and a hollow ridge made of synthetic resin at a predetermined pitch is formed on the outer wall of a body portion of the inner tube so that the ridge is on the outer side. And spirally wrap the ridge with a metal ridge reinforcement, and wrap the second strip of synthetic resin in a spiral so as to cover the top of the ridge. In the formed corrugated composite pipe, a corrugated composite in which a reinforcing material for an outer pipe that keeps the outer wall of the outer pipe of the outer pipe in a smooth state is provided in a state of being spanned between each adjacent top and top of the ridge. It is a tube.

  In the present invention, a pipe in which a pipe body and a reinforcing material that reinforces the pipe body are composed of a combination of different materials is called a composite pipe.

  According to the present invention, the outer tube reinforcing member provided between the outer tube and the ridge keeps the body outer wall of the corrugated composite tube smooth, and when an external force acts, It opposes the external force so that the outer wall does not deform.

  In the present invention, the outer tube can be formed so as to cover the top of the ridge, which is a part of the corrugated composite tube in the tube axis direction. Accordingly, it is possible to increase the pressure flattening strength of the specific portion while suppressing an increase in the weight of the corrugated composite pipe.

  In addition, if the above-mentioned part of the outer pipes are formed at both ends of the corrugated composite pipe, when connecting the corrugated composite pipes, the outer surface of the pipe end portion that becomes the joint portion becomes smooth, so that the connection work is easy. The water tightness can be improved.

  In the present invention, the outer tube reinforcing material can be formed of a strip-shaped metal thin plate wound on the protrusion at a predetermined pitch.

  In the present invention, when the outer pipe reinforcing material is disposed in a state where a gap is left at the top of the ridge, the ridge and the outer pipe can be fused and integrated through the gap.

  In the present invention, if the inner tube reinforcing member made of a thin metal plate is embedded in the inner tube in a spiral shape, not only the outer surface of the corrugated composite tube can be kept smooth but also the inner surface can be kept smooth.

  In the present invention, when the reinforcing material for the ridge has a pair of legs bent substantially parallel to the pipe axis direction on the hem side, the reinforcing material for the inner pipe is arranged so as to connect these legs. The external force applied to the tubular body can be received by the outer tube reinforcing member, the protrusion reinforcing member, and the inner tube reinforcing member, and the pressure-resistant flattening strength can be increased.

  In the present invention, when having a pair of legs bent substantially parallel to the tube axis direction on the skirt side of the reinforcing material for the ridge, one leg is extended toward the ridge adjacent to the leg. And it can form in the length substantially the same as the winding pitch of a protrusion. Thereby, it becomes possible to cause the reinforcing material for the ridges to function also as the reinforcing material for the inner tube for keeping the inner tube smooth.

  In the present invention, if a positioning portion for positioning the outer tube reinforcing material is formed in at least one of the outer peripheral portions of the ridge in the tube axis direction, the outer tube reinforcing material is accurately arranged at a predetermined position of the ridge. The smoothness of the corrugated composite pipe outer surface can be further increased.

  Outer pipes are formed at both ends of the corrugated composite pipe, and the ends of the corrugated composite pipe are cut in a direction perpendicular to the pipe axis direction to form hollow passages in the ridge, adjacent ridges, inner pipe, and outer pipe. By providing a water stop plug at least at the end of the hollow passage surrounded by the water channel, it is possible to shut off the water supply that connects the corrugated composite pipe in a spiral shape.

  In the present invention, polyethylene, polyvinyl chloride, polypropylene and other synthetic resin materials can be used as the synthetic resin material constituting the composite pipe.

  Further, as each reinforcing material, a metal reinforcing band plate such as an iron plate or a stainless steel plate having a thickness of 0.2 mm to 2 mm cut into a band plate shape can be used. In addition, if this metal reinforcing strip is coated with the same kind of resin as the inner tube (or outer tube), the reinforcing material and the inner tube (or outer tube) can be obtained by heating and melting the resin coating layer. Can improve the adhesion.

  The protrusions of the present invention include those having a cross-sectional shape of a rectangle, a square, a trapezoid, a triangle, and a semicircle.

  According to the corrugated composite pipe of the present invention, although it is a corrugated pipe, the water stop performance equivalent to that of the ring pipe can be obtained, and the composite pipes can be connected to each other without requiring complicated work. Further, the pressure-resistant flattening strength can be increased against the external force applied to the corrugated composite pipe.

  According to the present invention in which the outer tube is formed in a part of the corrugated composite tube, the pressure-resistant flattening strength can be increased in the portion where the outer tube is formed while reducing the weight of the corrugated composite tube. Moreover, if the said outer tube is provided in the both ends of a corrugated composite pipe, the watertightness of a joint part can be improved when corrugated composite pipes are connected.

  Hereinafter, the present invention will be described in detail based on the embodiments shown in the drawings.

  FIG. 1 shows an overall configuration of a corrugated composite pipe according to the present invention.

  A corrugated composite pipe (hereinafter abbreviated as a composite pipe) 1 has an inner pipe 2 having a smooth inner surface, and protrusions 3 are formed in a spiral shape at a predetermined pitch on the outer wall of the trunk of the inner pipe 2. A trough 4 is formed between the protrusion 3 and the adjacent protrusion 3. Thereby, the peak part and the trough part 4 which were formed with the protrusion 3 are formed alternately by the pipe-axis direction.

  The outer peripheral side of the ridge 3 is covered with an outer tube 5, and the outer tube 5 is provided in a state in which the tops of the ridge 3 are connected in the tube axis direction.

  Reference numeral 6 denotes a protrusion hollow part formed in the protrusion 3, and 7 denotes a valley side hollow part partitioned by the valley part 4 and the outer tube 5.

  FIG. 2 is an enlarged view of part C of FIG.

  In the cross-sectional structure shown in FIG. 2, the composite pipe 1 is composed of an inner pipe 2, an outer pipe 5, and a ridge 3 formed between the two pipes 2, 5, and a ridge for reinforcing the ridge 3. The outer tube reinforcing material 11 and the outer tube reinforcing material 11 for keeping the outer surface of the outer tube 5 in a smooth state are provided.

  When manufacturing the said composite pipe | tube 1, the inner pipe | tube 2 is continuously extruded as strip | belt-shaped resin with the extruder which is not shown in figure, and is supplied on a cylindrical shaping | molding roll (not shown) in a semi-molten state.

  The forming roll is composed of a plurality of roll pieces arranged in an inclined state with respect to the cylinder axis, and the extruded belt-like resin is wound around each of the inclined roll pieces in sequence, and the belt-like resin wound first. It is formed into a cylindrical shape by overlapping and fusing with the rear side edge portion.

  The reinforcing material 10 for the ridge is wound around the outer wall of the body portion of the inner tube 2 formed in this way, and a strip-shaped resin forming the ridge 3 is wound on the outer surface thereof.

  Next, the outer tube reinforcing material 11 is wound so as to communicate with the top of the protrusion 3, and the second belt-shaped resin forming the outer tube 5 is wound outside the outer tube reinforcing material 11.

  The protrusion 3 formed between the inner tube 2 and the outer tube 5 is formed in an angular wave having a rectangular cross section in this embodiment, and the protrusion reinforcing material 10 is formed on the inner surface of each protrusion 3. Is provided.

  This stiffening reinforcing member 10 is formed by processing a thin steel plate into a strip shape and corrugating it into a convex shape, and has a convex portion 10a projecting in the diametrical direction, and is formed at the bottom of the convex portion 10a. The pair of leg portions 10b, 10b are bent in opposite directions toward the tube axis direction.

Length s of these legs 10b has a gap w ₁ is set to a length that can be secured between the legs 10b of the ribs reinforcing material 10 adjacent butt the body portion outside wall of the inner tube 2 when Article 3 and the trough portions 4 are alternately formed, so as to center part 4a and the inner tube 2 transgressions fusion valley 4 through the gap w _1.

Further, the outer tube reinforcing member 11 laid in the tube axis direction on the top portion 3a of each protrusion 3 has a strip shape, and the length m of the outer tube reinforcing member 11 is the same as that of the adjacent outer tube reinforcing member 11. gap w ₂ is set so as to ensure during. Thereby, the top portion 3a of the protrusion, when the belt-like synthetic resin as the outer tube 5 is wound, so as to fuse protrusion 3 and the outer tube 5 transgressions through the gap w _2.

  According to the composite pipe 1 having the above-described configuration, the protrusion 3 is held in a rectangular shape by the protrusion reinforcing material 10, and the outer pipe 5 is held flat (flat) by the outer pipe reinforcing material 11.

  Conventionally, it is known that the ridge 3 is covered with a strip-shaped synthetic resin in a tubular shape. However, when the coated synthetic resin is cured, the outer tube is formed into a flat shape by bending between the ridges 3 by “sink”. It was difficult.

  On the other hand, in the present embodiment, the outer tube is provided with the outer tube reinforcing member 11 to eliminate the curvature of the outer tube, thereby realizing the composite tube 1 having a flat outer surface.

  When the outer tube reinforcing material 11 is curved upward due to thermal contraction in the tube axis direction after forming the composite tube, it is corrected to a flat shape by applying a pressing force from the outside of the composite tube 1 toward the tube center. be able to.

  FIG. 3 shows a joint structure when connecting the composite pipe 1 having the above-described configuration.

  When connecting the composite pipes 1 to each other, the connection side end 8 (or the connection side end 9) of the composite pipe 1 shown in FIG. 1 and the connection side end of another composite pipe 1 are opposed to each other. If 1 is a relatively small diameter (for example, the outer diameter is 300 mm or less), use a socket-type joint, and if it has a large diameter (for example, the outer diameter exceeds 300 mm), connect using an externally held split joint. To do.

  A connection method using a socket type joint will be described below.

  The connection side end of one composite pipe 1 is inserted into one side connection port 20a of the synthetic resin joint 20, and the other connection side end of the composite pipe 1 (not shown) is connected to the other side of the joint 20. Insert into the connection port 20b.

  In addition, a U-shaped groove portion 20c is formed in the circumferential direction at the central portion in the tube axis direction of the joint 20, and the depth of the groove portion 20c is determined on the left and right composite pipes 1 (on the left side in FIG. 3 (a)). It is formed so as to be substantially flush with the inner surface of the composite tube 1), thereby functioning as a positioning portion when the composite tube 1 is inserted, and when the insertion is completed, the connection side of the composite tube 1 The end face is closed.

  FIG. 3B is an enlarged view of a portion D in FIG.

  A packing 21 in which a synthetic rubber is formed in a cylindrical shape is attached to the outer wall of the body portion at the connection side end of the outer tube 5.

  The packing 21 has a plurality of wedge-shaped projections 21a formed in the connecting direction. The composite tube 1 can be easily inserted in the connecting direction, and acts as a resistance in the reverse direction. It is designed to prevent it from coming off.

  Since the outer wall of the body portion of the outer tube 5 of the composite tube 1 shown in the present embodiment is formed flat, the valley portion 22a does not exist like the conventional corrugated pipe 22 shown as a comparative example in FIG. Therefore, in this embodiment, the block for water stop for filling a trough part, and the caulking material for water stop are not required. Moreover, the packing 21 used in the present embodiment does not need to secure the height h (see FIG. 4B) for filling the valley portion 22a unlike the packing 23 shown in FIG. The thickness can be reduced, whereby the adhesion between the packing 21 and the outer tube 5 and between the packing 21 and the joint 20 can be increased to obtain a stable water stop effect.

  The packing 21 is not limited to the above-described synthetic rubber, and a water-swellable sealing material based on synthetic rubber or nonwoven fabric can also be used. When a water-expandable sealing material is used, the packing expands when water enters and the adhesion between the composite pipe 1 and the joint 20 is increased, so that the liquid tightness is improved and the difficulty of being removed is improved.

  Next, the configuration of the connection side end of the composite pipe 1 will be described. The connection side end face of the composite pipe 1 is cut in a direction perpendicular to the pipe axis PA, and the connection side end face is shown in FIG.

  In the drawing, the end surfaces of the inner tube 2 and the outer tube 5 appear concentrically on the end surface of the composite tube 1, and an annular groove M appears between the inner tube 2 and the outer tube 5 except for the range E. The range E is a cut surface of the ridge 3.

  In addition, a leg cut surface 10c of the reinforcing member 10 for protrusions arranged on the inner surface of the protrusion 3 appears on the outer periphery of the inner tube 2.

  The leg cutting surface 10c appears in an arc shape at the portion where the ridge 3 is cut, communicates with the outer tube 5 for the range E (see 10d in the figure), and for the outer surface appearing on the inner periphery of the outer tube 5 The reinforcing member 11 is substantially connected to the cut surface 11a.

  In FIG. 6, a symbol M indicates a valley 4 between the ridges 3, which is a passage that spirally communicates from one end of the composite pipe 1 to the other end, and a symbol N is a spiral shape in the ridge 3. A passage that communicates with

  As described above, both the passage M and the passage N communicating with each other in the valley portion 4 and the protrusion 3 form a water supply, and are closed by a water stop plug described below.

  (a) When a solid long filler made of thermoplastic resin or thermosetting resin is used as the plug, the cross-sectional shape of the plug 24 inserted into the passage M matches the cross-sectional shape of the valley 4. Use what is shaped like this. On the other hand, the plug body 25 to be inserted into the passage N is formed so as to match the hollow cross-sectional shape of the protrusion 3.

  If the insertion length of the plugs 24 and 25 is at least 1/8 or more of the outer circumference of the composite pipe 1, the water supply can be shut off for the passages M and N.

  As a method for inserting the plug, it may be wound and inserted at the same time as the composite tube 1 is formed, or may be inserted in a separate step after the composite tube 1 is formed.

  (b) When a foaming resin such as foamed urethane foam is used as the plug, first, the composite pipe 1 is laid sideways, a nozzle of a filling machine (not shown) is inserted from the passage M, and part of the passages M and N is inserted. A foamable resin (for example, a mixture of two liquids such as polyol and isocyanate) is injected. The injected foamable resin reacts in the passages M and N to expand and harden in a state where a part of the passage is blocked. This foamed resin is used as a foamable resin mold (resin mold) to be injected next for water stoppage.

  Next, when foamable resin is injected into the passages M and N, the foamable resin expands by reaction in the passages M and N between the resin mold and the composite pipe end face, and the passages M and N are completely blocked. To do.

  Conventionally, in the corrugated pipe not provided with the outer pipe, since the trough 4 is open, the adhesion with the trough 4 could not be improved even if the water blocking block was mounted. Since the outer tube 5 is provided, the trough 4 is sealed, and filling with foamable resin can increase the packing density of the foamable resin and can be closely adhered to the trough 4 to increase the water stoppage. .

The foamable resin is not particularly limited as long as it forms closed cells, but has a predetermined strength (for example, the core density of the foamed molded product) that is excellent in water resistance and secures water pressure in order to ensure liquid-tightness. Is preferably 50 kg / m ³ or more).

  Also, when foaming, a mold is attached to the end face of the composite tube 1, but if a mesh-like glass cloth is disposed on the inner surface side of the mold and the foamed resin is impregnated with the glass cloth, The foamed resin skin layer can have an FRP structure to increase the strength.

  (c) When an inorganic filler, specifically mortar, is used as the plug, mortar obtained by blending Portland cement, sand and water is poured into the passages M and N. When mortar is poured into the passages M and N and cured, the strength of the mortar is added to the strength of the composite pipe 1 itself, so that the pressure-proof flattening strength can be further increased.

  Moreover, the said mortar may add the polymer as an adjuvant of cement. What added a polymer has the advantage that the tensile strength of mortar can be raised.

  Furthermore, the weight of the filler can be reduced by mixing, as an aggregate, a material having a low specific gravity such as styrene resin particles or pearlite, which is mixed into the mortar and uniformly dispersed in the cement using a dispersant.

  The filling of the plug body described above is performed at the factory as a water stop treatment at the end of the pipe when the composite pipe 1 is manufactured.

  7 to 11 show other embodiments of the composite pipe 1 according to the present invention.

  In the following description, the same components as those of the composite pipe 1 shown in FIG.

  First, the composite pipe 30 shown in FIG. 7 is provided with double inner pipes 31 on the inner peripheral surface of the inner pipe 2.

  Between the double inner pipes 2 and 31, a strip reinforcing material 32 wound at a predetermined pitch is embedded. The strip-shaped reinforcing material 32 is arranged so as to straddle the leg portions 10b of the protrusion reinforcing material 10, and a predetermined gap t is secured between the strip-shaped reinforcing materials 32. The double inner pipes 2 and 31 are fused and integrated through the gap t.

  According to the composite pipe 30 having the above configuration, the outer surface of the outer tube 5 is formed flat, and the inner surface of the inner tube 31 is also formed flat. Moreover, since it can withstand the pressure from inside and outside, the withstand pressure flattening strength can be further increased.

  In FIG. 8, the protrusion 35 formed in a spiral shape between the outer tube 33 and the inner tube 34 is corrugated in a triangular shape.

  In this configuration, the reinforcing material 36 for the protrusions is provided on the inner surface side of each protrusion 35. This reinforcing member 36 for ridges consists of a thin steel plate processed into an inverted V-shaped cross section, and holds the cross-sectional shape of the ridge 35 in a triangular shape. Further, an outer tube reinforcing member 37 is provided on the inner surface side of the outer tube 33 so as to communicate with the top portion 35 a of the protrusion 35.

  The outer tube reinforcing material 37 is formed by processing a thin steel plate into a strip shape, and keeps the outer surface of the outer tube 33 flat.

  FIG. 9 shows a ridge reinforcing member 41 provided on the inner side of a ridge 40 formed into a square wave, and step portions (positioning portions) 41b are formed on both sides (tube axis direction) of the upper surface 41a. .

  The step portion 41b is formed one step lower than the upper surface 41a, and the end portion in the tube axis direction of the outer tube reinforcing material 11 is made to correspond to the step portion 41b. Accordingly, when the outer pipe reinforcing material 11 is disposed so as to straddle the ridge 40, the outer pipe reinforcing material 11 can be accurately positioned at a predetermined position (step portion 41b) of the ridge 40. It becomes like this. As a result, the composite pipe 1 having a flat outer surface can be manufactured with higher accuracy.

  In FIG. 10, the shape of the ridge 42 is formed in a trapezoidal shape.

  On the inner side of the ridge 42, a ridge reinforcing material 43 processed into a trapezoid is provided, and step portions 43b are formed on both sides of the upper surface 43a of the ridge reinforcing material 43.

  The step portion 43b is formed one step lower than the upper surface 43a, and the end portion in the tube axis direction of the outer tube reinforcing material 11 is made to correspond to the step portion 43b. Also in this case, similarly to the step portion 41 b shown in FIG. 7, when the outer pipe reinforcing material 11 is arranged so as to straddle the ridge 42, the outer pipe reinforcing material 11 is placed at a predetermined position of the ridge 42 ( It becomes possible to accurately position the step 43b).

  9 and 10 are preferably formed on both sides of the outer periphery of the protrusion 40 (42) in the tube axis direction, but if formed on at least one of them, a positioning effect is obtained. Can be obtained.

  In the composite tube 44 shown in FIG. 11, the ridge 45 is spirally wound around the outer wall of the body portion of the inner tube 2 formed in a cylindrical shape in the same manner as the composite tube described above. The outer tube 5 is formed in a cylindrical shape so as to communicate with the upper surface 45 a of the protrusion 45.

  Further, the inner side of the protrusion 45 is reinforced with a metal protrusion reinforcing material 45b, and two leg portions bent substantially parallel to the tube axis direction are formed on the skirt side of the protrusion reinforcing material 45b. Is formed.

  In the drawing, the right leg 45c is formed to be short so as to be approximately half the valley width of the adjacent ridge 45, and the left leg (one leg) 45d is adjacent to the ridge 45. It extends toward 45 and is formed to have substantially the same length as the winding pitch of the protrusion 45.

  Accordingly, when the protrusion 45 is wound around the outer wall of the body portion of the inner tube 2, the leg 45c of the protrusion 45 to be wound next overlaps the leg 45d of the protrusion 45 that has been wound first. To go.

  Thereby, even if it does not use the strip | belt-shaped reinforcement material 32 which consists of another member as shown in FIG. 7, the inner pipe | tube 2 can be reinforced and the intensity | strength and inner surface smoothness can be improved. In addition, the number of steps for manufacturing the composite pipe 44 can be reduced.

Incidentally, the clearance resin portion of the ridges to each other and integrated with fused by a gap w ₃ is secured, also at the tip of the leg portion 45d is formed between the projections 45 adjacent to the leg portion 45c since w ₄ is ensured, the resin portions of the inner tube 2 and the protrusion 45 is adapted to integrally fused.

  According to the composite tube 44 having the above configuration, the outer surface of the outer tube 5 is formed flat, and the inner surface of the inner tube 2 is also formed flat. Moreover, since it can withstand the pressure from inside and outside, the withstand pressure flattening strength can be further increased.

  According to the composite pipes shown in FIGS. 6 to 11, since the outer surfaces of the outer pipes are all smooth, when connecting the composite pipes using a half joint, for example, butyl rubber If the sheet is wound by a predetermined width and a half joint is attached from above, a gap is not formed between the half joint and the outer pipe, and the water tightness of the pipe joint portion can be improved.

  Specifically, in a conventional corrugated pipe of φ600 mm whose outer surface is formed in a corrugated corrugated shape, an internal pressure of about 0.02 to 0.05 MPa is obtained even when a caulking material is filled in a wave trough and subjected to a water stop treatment On the other hand, when the composite pipes of φ600 mm according to the present invention were arranged to face each other and connected using a half joint, the leakage could be maintained up to an internal pressure of 0.35 mPa.

  As described above, according to the composite pipe of the present invention, the water stopping performance can be improved and, at the same time, the workability can be improved because the caulking material filling operation is not required.

  Next, FIG. 12 shows an outer tube formed in part of the tube axis direction of the composite tube of the present invention.

  The composite pipe 50 shown in the figure has an inner pipe 51 having a smooth inner surface, and a protrusion 52 is spirally wound around the outer wall of the inner pipe 51 at a predetermined pitch. Crests 53a and troughs 53b formed between adjacent protrusions 52 are alternately formed in the tube axis direction.

  The inner tube 51 is formed in a cylindrical shape, and the protrusion 52 is formed by winding a belt-shaped resin around the outer surface of a reinforcing member for protrusions to be described later.

  The top portions 52a of the plurality of protrusions 52 are covered with an outer tube 54 provided in a state where they are communicated, and the outer tube 54 is provided at both ends of the composite tube 50, specifically, at the right end. This is a range indicated by “L” at the left and right end portions. In this outer tube forming portion 55, 56 indicates a protruding hollow portion formed in the protruding portion 52, and 57 indicates a valley-side hollow portion partitioned by the valley portion 53 b and the outer tube 54.

  FIG. 13 is an enlarged view of portion F in FIG.

  In the cross-sectional structure shown in FIG. 13, in the composite pipe 50, a ridge reinforcing material 58 for reinforcing the ridge 52, and an outer pipe reinforcing material 59 for keeping the outer surface of the outer pipe 54 in a smooth state, Are provided.

  The method of manufacturing the composite pipe 50 is basically the same as the method of manufacturing the composite pipe 1 shown in FIG. 2, and the inner pipe 51 is continuously extruded as a strip-shaped resin by an extruder and formed into a cylindrical shape. Is done. A reinforcing member 58 for the ridge is wound around the outer wall of the body portion of the inner pipe 51, and a strip-shaped resin for forming the ridge 52 is wound on the outer surface thereof. In addition, the reinforcing material 58 for protrusions in this embodiment is formed in the square wave which has a trapezoid cross section.

  Next, a strip-shaped outer tube reinforcing member 59 is spirally wound so as to communicate with the peak portion 52a of the protrusion 52, and the outer tube 54 is formed on the outer side of the outer tube reinforcing member 59 as a support. A second belt-shaped resin is wound spirally.

  The protrusion reinforcing member 58 is formed by processing a thin steel plate into a strip shape and corrugating it into a convex shape, and includes a pair of convex portions 58a that are tapered and a skirt portion of the convex portion 58a. Leg portions 58b and 58b. Between these leg parts 58b and 58b, the resin which forms the protrusion 52 and the resin which forms the inner tube 51 come into direct contact and are fused to each other.

  Further, in the arrangement of the outer tube reinforcing material 59 installed in the tube axis direction with respect to the top portion 52a of each protrusion 52, a gap d is defined between the outer tube reinforcing materials 59. The resin forming the protrusion 52 and the resin forming the outer tube 54 are in direct contact with each other and fused together.

  According to the composite pipe 50 having the above configuration, the outer pipe forming portion 55 (see FIG. 12) is provided with the outer pipe 54 reinforced by the outer pipe reinforcing material 59, so that the strength of the end of the composite pipe 50 is increased. It is possible to prevent the end of the composite pipe 50 from being deformed when an external pressure is applied.

  In addition, when connecting the composite pipes 1 formed with the outer pipe forming portion 55, the outer surface of the outer pipe 54 is smooth, so that, for example, when a half joint is wound, there is a gap between the half joint. Since a wide contact area can be ensured, the water tightness of the pipe joint portion can be improved.

  Further, when the composite pipe 50 and the joint are connected by welding or an adhesive, or when the outer surface of the end of the composite pipe 50 is smooth, such as when a fitting is interposed with a packing sheet or the like, under any connection conditions It is advantageous and easy to install.

  On the other hand, the range other than the outer tube forming portion 55 formed in the composite tube 50 is reduced in weight only by the combination of the inner tube 51 and the reinforced protrusion 52, so that the workability of the piping is reduced. I will not let you.

  12 shows the configuration in which the outer tube forming portion 55 is provided at both ends of the composite tube 50. For example, when manufacturing a long composite tube 50 having a diameter of 1000 mm, the outer tube is formed at regular intervals (for example, 5 m). If a plurality of forming portions 55 (for example, 1 m) are formed and cut in the diametrical direction at the central portion in the tube axis direction of one of the outer tube forming portions 55, the cut portion functions as a joint portion with a smooth outer surface. .

  In the composite pipe 50 shown in the second embodiment, the shape of the protrusion 52 may have a rectangular cross section shown in FIG. 2, and a triangular cross section as shown in FIG. It may have.

  Moreover, as shown in FIG.9 and FIG.10, the step part for positioning the reinforcing material for outer tubes can also be provided.

  Furthermore, the inner pipe 51 of the composite pipe 50 may be a double pipe as shown in the inner pipe of FIG. 7, and a band-shaped reinforcing material may be embedded between them.

It is a side view which has a partial notch which shows the whole structure of the composite pipe | tube which concerns on this invention. It is the C section enlarged view of FIG. (a) is the side view which has a notch which shows the joint structure using the composite pipe concerning this invention, (b) is the D section enlarged view. (a) is the side view which has a notch which shows the conventional joint structure shown as a comparative example, (b) is an enlarged view of packing. It is explanatory drawing which shows the connection side end surface of the composite pipe which concerns on this invention. It is sectional drawing which shows the water stop structure of the connection side end surface shown in FIG. It is principal part side surface sectional drawing which shows the 1st modification of the composite pipe which concerns on this invention. FIG. 8 is a view corresponding to FIG. 7 showing a second modification of the composite pipe according to the present invention. FIG. 9 is a view corresponding to FIG. 7 showing a third modification of the composite pipe according to the present invention. FIG. 9 is a view corresponding to FIG. 7 showing a fourth modification of the composite pipe according to the present invention. FIG. 10 is a view corresponding to FIG. 7 showing a fifth modification of the composite pipe according to the present invention. FIG. 3 is a view corresponding to FIG. 1 showing another embodiment of the composite pipe according to the present invention. It is the F section enlarged view of FIG. It is side surface sectional drawing which shows the structure of the conventional corrugated composite pipe. (a) And (b) is explanatory drawing which shows the water stop method of the conventional corrugated composite pipe. It is a side view which shows the joint structure of the conventional corrugated composite pipe.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Composite pipe 2 Inner pipe 3 Projection 3a Top part 4 Valley part 5 Outer pipe 6 Projection hollow part 7 Valley side hollow part 8,9 Connection side edge 10 Projection part 10a Projection part 10b Leg part 11 Reinforcement for outer pipe Member 44 Composite tube 50 Composite tube 51 Inner tube 52 Projection 54 Outer tube 55 Outer tube forming part 56 Projection hollow part 57 Valley side hollow part 58 Projection reinforcing material 59 Outer tube reinforcement

Claims (10)

A belt-shaped synthetic resin is spirally wound to form an inner tube, and a hollow ridge made of synthetic resin at a predetermined pitch is spirally formed on the outer wall of the inner tube of the inner tube so that the ridge is on the outside. A corrugate that is wound and reinforced with a metal ridge reinforcement, and a second strip of synthetic resin is spirally wound to cover the top of the ridge to form an outer tube In composite tubes,
A corrugated composite pipe characterized in that a reinforcing material for an outer pipe that keeps the outer wall of the body section of the outer pipe in a smooth state is provided in a state of being spanned between the adjacent top portions of the ridges. .   The corrugated composite pipe according to claim 1, wherein the outer pipe is a part of the corrugated composite pipe in a tube axis direction and is formed so as to cover a top portion of the protrusion.   The corrugated composite pipe according to claim 2, wherein the outer pipe is formed at both ends of the corrugated composite pipe.   The corrugated composite pipe according to any one of claims 1 to 3, wherein the reinforcing material for the outer pipe is formed of a strip-shaped metal thin plate wound at a predetermined pitch on the ridge.   The outer pipe reinforcing material is arranged in a state where a gap is left at the top of the ridge, and the ridge and the outer pipe are configured to be fused through the gap. The corrugated composite pipe according to any one of claims.   The corrugated composite pipe according to any one of claims 1 to 5, wherein a reinforcing material for an inner pipe made of a thin metal plate is embedded in the inner pipe in a spiral shape.   The reinforcing material for a ridge has a pair of legs bent substantially parallel to the pipe axis direction on the hem side, and the reinforcing material for an inner pipe is disposed so as to connect the legs. Item 6. The corrugated composite pipe according to item 6.   A pair of leg portions bent substantially parallel to the tube axis direction on the skirt side of the reinforcing material for the ridge, and one leg portion is extended toward the ridge adjacent to the leg portion; The corrugated composite pipe according to any one of claims 1 to 5, wherein the corrugated composite pipe is formed to have substantially the same length as a winding pitch of the ridges.   The corrugated composite pipe according to any one of claims 1 to 8, wherein a positioning portion for positioning the reinforcing member for outer pipe is formed on at least one of the outer peripheral portions of the ridges in the pipe axis direction.   The outer pipe is formed at both ends of the corrugated composite pipe, the end of the corrugated composite pipe is cut in a direction orthogonal to the pipe axis direction, the hollow passage in the ridge, the adjacent ridge, and the above The corrugated composite pipe according to any one of claims 1 to 9, wherein a stopper for water stop is provided at least at the end of the hollow passage surrounded by the inner pipe and the outer pipe.

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