JPH02125193A - Plastic-lined concrete pipe - Google Patents

Abstract

PURPOSE:To generate no difference of shrinkage or expansion due to temperature changes by filling concrete on the outer periphery of a lengthy plastic band plate provided with multiple concrete sticking projections and integrally hardening it. CONSTITUTION:A lengthy plastic band plate 4 provided with multiple concrete sticking projections 5 in the longitudinal direction is spirally wound so that the concrete sticking projections 5 are located outside to form a plastic cylinder 3. Concrete is hardened and integrated on the outer periphery of this cylinder 3. Both ends of the cylinder 3 are heated and expanded in diameter, and plastic end rings 9 and 9' are stuck on inner peripheries of expanded sections 8 and 8' to form an hourglass shape. As a result, a concrete pipe is made nearly parallel with the direction of the stress generated by a load after the concrete pipe is buried, and the reduction of strength can be prevented. No difference of shrinkage or expansion due to temperature changes is generated, and no peeling occurs.

Description

[Detailed Description of the Invention] In recent years, there has been a demand for corrosion-resistant sewage pipes due to deterioration in water quality, and attempts have been made to line concrete pipes with plastic as a countermeasure. The caliber of the pipes varies for each stage, and they range up to large diameters, so it is technically and economically difficult to extrude thin-walled plastic circular pipes of each caliber for lining.
Moreover, if it is made thin, there is a risk that it will easily peel off from the concrete surface. For this reason, even if protrusions are provided by extrusion molding.

This is undesirable because it significantly reduces the pressing load of the concrete pipe because it is formed vertically parallel to the pipe axis.
In the present invention, a plastic cylinder 3 is formed by spirally winding a long plastic strip 4 provided with several concrete attachment protrusions 5 in the longitudinal direction so that the concrete attachment protrusions 5 are on the outside. This is a method of forming a concrete pipe with a plastic plate lining on the inner peripheral surface by pouring concrete into the outer periphery and letting it harden and integrate. By adopting a plastic strip plate 4 that can be easily extruded, several longitudinal concrete attachment protrusions 5 having shapes as illustrated in FIGS. 4, 5, 6, and 7 are formed on one side thereof. can be extruded at the same time.

By winding this plastic strip 4 spirally with the concrete attachment protrusion 5 facing outward, a plastic cylinder 3 having a protrusion 5 that is embedded in the concrete can be obtained. By winding the plastic strip 4 spirally, the direction of the longitudinal protrusions 5 is arranged in the direction of the circular layer of the plastic cylinder 3, so that it is almost parallel to the direction of stress caused by the load after concrete management. It is possible to avoid a decrease in strength. Concrete is injected into the outer periphery of this plastic cylinder 3 and is allowed to harden to form an integrated structure, so that the protrusions 5 are buried in the wall of the concrete pipe. Therefore, the two are completely and closely fixed, and there is no difference in shrinkage or expansion caused by temperature changes, and separation between them cannot occur due to bending of the tube.

Figures 4, 5, 6, and 7 are partial cross-sections of long plastic strips 4 that are helically wrapped once and stacked and joined together with the concrete attachment protrusions 5 on the outside. Figure 4 shows a plastic circle fj3 formed by pressing and bonding the other t/#7 on one edge 6 of the plastic strip 4 in the direction of the arrow. be.

FIG. 5 shows a state in which the edges 6 and 7 of FIG. 4 are interlocked with each other by providing irregularities on their surfaces to increase the adhesive strength. Figure 6 shows a method of shifting the other edge 7 that overlaps one a6 of the plastic strip plate 4 in the direction of the horizontal arrow when gluing, interlocking the ends, and then press-bonding in the direction of the vertical arrow. . Also, Fig. 7 shows a case in which one edge 86 and the other edge 7 are firmly connected and prevented from returning by applying adhesive and shifting them in the direction of the horizontal arrow. By continuing to adhesively bond one edge 6 to the other edge 7 while winding a long plastic strip 4 in a spiral shape, a long plastic cylinder 3 can be formed using one plastic strip 4. can be formed. This plastic cylinder 3 is assembled into a concrete pipe formwork, concrete is injected between the plastic cylinder 3 and the formwork, and concrete is left to harden to be integrated with the cylinder 3, thereby forming a plastic lining on the inner peripheral surface. To manufacture a concrete pipe that is sticky and whose lining does not peel off easily.

Next, in order to cover the ends of this concrete pipe with plastic plates, both ends of the plastic cylinder 3 are heated to soften them and inserted into a cylindrical mold, as shown in Figures 1, 2, and 3. The diameter is enlarged and cooled as it is to form enlarged diameter parts 8 and 8', and plastic tube end rings 9 and 9 are attached to the inner peripheral surface of the enlarged diameter parts 8 and 8'.
The insertion parts 10 and lO' of ' are press-fitted and glued to form a drum shape, which is attached to a concrete pipe formwork, concrete is injected, and it is left to harden to be integrated, thereby making the inner circumferential surface and end surface plastic. Concrete pipes lined with this material can be manufactured.

The pipe end rings 9 and 9' in this figure are L-shaped and consist of an insertion part lO and a flange part 11. A rubber ring 12 is fitted in contact with the outer periphery of the flange part 11, and a female socket By pushing a concrete pipe with a male spout into a concrete pipe with a male spout, the compressed rubber ring 13 is compressed to maintain watertightness.

Further, in FIGS. 8 and 9, both ends of the plastic cylinder 3 are heated to expand the diameter, and deep grooves for rubber rings are formed in the inner circumferential surfaces of the expanded diameter parts 8 and 8' at the center of the flange parts 14 and 14'. The plastic pipe end rings 13 and 13' having the diameters 15 and 15' are glued together to form a drum shape, which is attached to a concrete pipe formwork, and concrete is poured into the mold and allowed to harden to form a single piece. 15 and 15'
The structure of concrete pipes is shown in which the concrete pipes are joined by inserting a cylindrical rubber ring 16 containing a cylindrical core 17 therein.

The insertion portions 10 of the tube end rings 13 and 13' in this figure are press-fitted into the enlarged diameter portions 8 and 8' of the plastic cylinder 3 and are bonded.

The cylindrical rubber ring 16 has a built-in cylindrical core 17 in the center, so when the rubber ring is inserted, the rubber on the outer periphery is pulled, allowing it to be inserted deeply with little resistance, and after insertion, the rubber shrinks and has a restoring effect, making it even more watertight. This increases the durability and makes it durable for many years of use. As shown in FIG. 10, the diameter of the cylindrical core 17 can be increased or decreased by cutting grooves 18 alternately in the axial direction, so that it follows the diameter of the deep groove 15 for the rubber ring. Therefore, the compression margin of the cylindrical rubber ring 16 is always equal to the thickness of the rubber ring 16,
This is the difference from the width of the deep groove 15, and watertightness is maintained.

In addition, by making the central portion 19 of the cylindrical core 17 thin and flexible, even if the centers of the two concrete pipes to be connected are slightly shifted, the cylindrical rubber ring 16 will follow the deep groove 15, impairing watertightness. Never.

[Brief explanation of the drawing]

The figures show an example of the implementation of the present invention, and Fig. 1 is a longitudinal cross-sectional view of a plastic-lined concrete pipe according to the present invention;
Figure 2 is its side view. Figure 3 is an X-Y sectional view of Figure 1, Figures 4, 5, and 6.
7 and 7 show cross-sectional views of long plastic strips 4 of four different shapes wrapped around each other and bonded together.
Fig. 8 is a longitudinal cross-sectional view of a plastic-lined concrete pipe using a cylindrical rubber ring 16, Fig. 9 is a side view thereof, and Fig. 1
Figure O is a longitudinal sectional view of the cylindrical rubber ring 16. FIG. 11 is a side view thereof. 1 ・・・・・・・・・Concrete pipe 2・・・・・・
・・・Reinforcement bar 3 ・・・・・Plastic cylinder 4・・・・
...Plastic strip 5...Protrusion for attaching concrete to plastic strip 4 6.7 ...Both sides of plastic strip 4 8.8
'... Expanded diameter part of plastic cylinder 3 9.9'10.10'11.11'14.14'15.15' Pipe end ring using compression type rubber ring 12 Pipe end ring 9, 9' or 13.13' insertion part Pipe end ring 9, 9' flange part Compressed rubber ring Pipe end ring using cylindrical rubber ring 16 Pipe end ring 13, 13' flange part Flange part 14.14 Deep groove cylindrical rubber ring for rubber ring of 'Cylindrical core of cylindrical rubber ring 16 Center part of kerf cylindrical core 17 of cylindrical core 17 I! J bait + concave 5''' μs 16 prisoners 7 figures 10 sides 1 Jll prisoners

Claims (3)

[Claims] (1) A plastic cylinder 3 is formed by spirally winding a long plastic strip 4 provided with several concrete attachment protrusions 5 in the longitudinal direction so that the concrete attachment protrusions 5 are on the outside; A method of forming a concrete pipe with a plastic plate lining on the inner circumference by pouring concrete into the outer circumference and allowing it to harden and integrate. (2) In the concrete pipe according to claim 1, both ends of the plastic cylinder 3 are heated to expand the diameter, and plastic pipe end rings 9 and 9' is glued to form a drum shape, this is attached to a concrete pipe formwork, concrete is injected, it is left to harden, and the structure of a concrete pipe is made by lining the inner circumferential surface and end surface with plastic material. . (3) In the concrete pipe according to claim 1, both ends of the plastic cylinder 3 are heated to expand the diameter, and the center of the flange parts 14 and 14' is placed on the inner peripheral surface of the expanded diameter parts 8 and 8'. Plastic pipe end rings 13 and 13', which have deep grooves 15 and 15' for rubber rings on the parts, are glued to form an hourglass shape, which is then attached to a concrete pipe formwork, concrete is poured in, and it is allowed to harden as it is to be integrated. A concrete pipe structure in which a cylindrical rubber ring 16 having a built-in cylindrical core 17 is inserted into the deep rubber ring grooves 15 and 15' to join them.