CN204604936U - A kind of polypropylene skeleton strengthens bellows - Google Patents

Abstract

The utility model discloses a polypropylene skeleton reinforced corrugated pipe, which is formed by direct helical winding of multiple hollow pipes and being fixed in close contact with each other. The hollow pipes are in close contact with each other and have more contact areas, which can ensure fixed connection. It has high strength, saves processing and manufacturing procedures, and has good ring stiffness and high strength, which solves the problems of ordinary bellows in the past. This utility model is used in the field of bellows production.

Description

A polypropylene skeleton reinforced bellows

technical field

The utility model relates to the field of corrugated pipe production, in particular to a polypropylene skeleton reinforced corrugated pipe.

Background technique

The outer corrugated plastic pipe structural wall pipe with hollow reinforcing ribs is widely used in the construction of municipal sewage pipelines because of its good pipe-soil interaction and ring stiffness. At present, there are generally three methods for manufacturing the outer corrugated plastic wound structural wall pipes with hollow reinforcing ribs.

In the first kind, at first the first extruder extrudes the molten strip-shaped plastic sheet, and then makes the sheet continuously and regularly side by side and spirally wound on a circular forming cylinder with many active rotating small rollers. At the same time, another extruder extrudes trapezoidal tubular reinforcing ribs, and after being water-cooled and vacuum shaped, it is pressed across the lap joints of the adjacent edges of the strips of plastic sheets on the tube wall in the same spiral winding manner. The bottom surface of the rib is properly heated, and because the plastic sheet is in a semi-molten state, after being rolled by the pressure roller, the tubular reinforcing rib and the two overlapping strip plastic sheets are fused together to form a hollow reinforcing rib. External corrugated plastic wound structural wall tubing. However, this process has the following defects: (1) Since the rib is wound after cooling and shaping, its height cannot be too large, so the moment of inertia of the tube wall after forming is small; (2) The bonding between the rib and the tube wall It is difficult to control. If the temperature of the strip plastic sheet is too low, the bonding will be poor. If the temperature is too high, the strip plastic sheet will fall from the forming roller and it will be difficult to control the molding; (3) After the bonding is completed, strengthen There are always gaps on the sides of the ribs, resulting in stress concentration. When the ambient temperature changes alternately, the welded surface will gradually crack from the gaps, which will easily cause the separation of the pipe wall and the ribs and collapse.

In the second type, what is first extruded by the first extruder is a special-shaped rectangular tube with a fin of an appropriate shape for mutual welding on both sides of the bottom surface. After the special-shaped rectangular tube is vacuum cooled and shaped, it is spirally wound on the forming drum Then, the second extruder continuously extrudes molten glue to the connecting parts of adjacent fins of side-by-side spiral-wound special-shaped rectangular tubes, and is welded together by pressing rollers. This process has the following disadvantages: the welding position is at the weakest part of the pipe, and the welding surface is small and the amount of melt glue is small, thereby reducing the overall bending strength of the pipe.

The third type is to first extrude the continuous two sides of the plastic special-shaped strips with hollow hollows on both sides, and the plastic special-shaped strips are spirally wound on the continuously rotating forming drum side by side, so that A gap is formed between the two tubular protrusions of the adjacent plastic profiled strips, and then the second extruder continuously squeezes molten plastisol into the gap, and the two tubular protrusions are tightly pressed after being rolled by the pressure roller. The ground is fused into one body, the two tubular protrusions are fused to form a hollow reinforcing rib on the outer wall of the pipe, and the side fusion parts of the two tubular protrusions form a reinforced inner rib. This process has the following disadvantages: the hollow reinforcing ribs are all formed by plastic special-shaped strips, so the formed outer corrugated plastic pipe structure wall pipe has a large weight and is not convenient for transportation.

The common wound corrugated pipes generally require multiple winding and rolling processes, which increases the manufacturing process of the corrugated pipes, makes the manufacturing process more complicated, and also increases the manufacturing cost of the production machine. Moreover, such corrugated pipes usually have external threads, which is not conducive to the transportation of the corrugated pipes.

Therefore, it is necessary to provide a corrugated pipe with a simpler manufacturing process and meet the requirements of use, so as to solve the above problems.

Utility model content

In order to solve the above problems, the utility model provides a polypropylene skeleton reinforced corrugated pipe with a simpler process.

The technical scheme that the utility model solves its technical problem adopts is:

A polypropylene frame reinforced corrugated pipe includes a pipe body formed by spirally winding a strip material, the strip material is a hollow pipe material or several hollow pipe materials parallel to each other and the adjacent surfaces are closely attached and fixed.

As a further improvement of the technical solution of the utility model, each hollow pipe includes a plastic corrugated pipe body disposed inside the hollow pipe and a PE coating layer wrapped outside the plastic corrugated pipe body, and two adjacent hollow pipes are tightly connected to each other. The affixed PE covering sticks tightly to fix it.

As a further improvement of the technical solution of the utility model, the cross-section of each hollow pipe is rectangular or parallelogram.

As a further improvement of the technical solution of the utility model, the cross-section of each hollow pipe is trapezoidal, and two adjacent hollow pipes are closely fixed to form a strip with a rectangular or parallelogram shape.

Beneficial effects of the utility model: since the corrugated pipe is directly helically wound by multiple hollow pipes and fixed closely to each other, the hollow pipes are closely attached to each other and have more contact areas, which can ensure the strength of the fixed connection and save processing at the same time The production process, and has better ring stiffness and higher strength, which solves the problems of ordinary bellows in the past.

Description of drawings

Below in conjunction with accompanying drawing, the utility model is further described:

Fig. 1 is a schematic diagram of the cross-sectional structure of the bellows wall of the embodiment of the utility model.

Detailed ways

Referring to Fig. 1, the utility model is a polypropylene skeleton reinforced corrugated pipe, which includes a pipe body formed by spirally winding a strip, and the strip is a hollow pipe or several hollow pipes that are parallel to each other and whose adjacent surfaces are closely attached to each other. .

Since the corrugated pipe is directly helically wound by multiple hollow pipes and fixed closely to each other, the hollow pipes are closely attached to each other and have more contact area, which can ensure the strength of the fixed connection, save the processing and manufacturing process, and has better Excellent ring stiffness and high strength solve the problems of ordinary bellows in the past.

As a preferred embodiment of the present utility model, each hollow pipe includes a plastic corrugated pipe body 1 disposed inside the hollow pipe and a PE coating layer 2 wrapped outside the plastic corrugated pipe body 1, and two adjacent hollow pipes pass through The PE covering layers 2 that are in close contact with each other are fixed in close contact.

As a preferred embodiment of the present invention, the cross section of each hollow pipe is rectangular or parallelogram.

As a preferred embodiment of the present invention, the cross-section of each hollow pipe is trapezoidal, and two adjacent hollow pipes are closely fixed to form a strip with a rectangular or parallelogram shape.

The corrugated pipe can also be formed by spiral winding of a single hollow pipe, and the processing speed of the corrugated pipe can be improved by sequential spiral winding of multiple hollow pipes parallel to each other, and the productivity can be improved, and the distance between the hollow pipes can be better guaranteed. Time, better guarantee the firmness of its connection.

The above-mentioned method can be produced by ordinary winding structure wall pipe production equipment equipped with corresponding touch heads, shaping sleeves and auxiliary pressure rollers, the equipment investment is small, and it can be widely popularized and applied.

Certainly, the invention of the utility model is not limited to the above-mentioned embodiment, and those skilled in the art can also make equivalent modifications or replacements without violating the spirit of the utility model. within the bounds of the requirements.

Claims (4)

1. A polypropylene skeleton reinforced corrugated pipe, comprising a pipe body formed by spirally winding a strip, characterized in that: the strip is a hollow pipe or several hollow pipes that are parallel to each other and adjacent surfaces are closely attached to and fixed . 2. The polypropylene skeleton reinforced corrugated pipe according to claim 1, characterized in that: each of the hollow pipes includes a plastic corrugated pipe body disposed inside the hollow pipe and a PE coating wrapped outside the plastic corrugated pipe body Layer, two adjacent hollow pipes are fixed by the PE coating layer which is close to each other. 3. The polypropylene framework reinforced corrugated pipe according to claim 2, characterized in that: the cross section of each said hollow pipe is rectangular or parallelogram. 4. The polypropylene skeleton reinforced corrugated pipe according to claim 2, characterized in that: the cross-section of each of the hollow pipes is trapezoidal, and the outer shape of two adjacent hollow pipes is rectangular or Parallelogram strips.