High-ring-stiffness hollow wall pipe and machining device thereof

Abstract

The utility model discloses a hollow wall pipe with high ring stiffness and a processing device thereof, the hollow wall pipe comprises a hollow pipe body (100), a plurality of through holes (200) are annularly distributed on the periphery of the pipe wall of the hollow pipe body (100), the cross section of each through hole (200) is round or square, two ends of each through hole (200) form an arc-shaped side wall (300), and the through holes (200) are communicated with the through holes (200). The length direction of the through holes (200) is the same as the length direction of the hollow pipe body (100), the adjacent through holes (200) are separated from each other, and the thicknesses of the pipe walls, around the through holes (200), of the hollow pipe body (100) are different. According to the utility model, the compressive strength of the hollow wall pipe can be improved, and the stability of the hollow wall pipe during extrusion molding is ensured.

Description

Technical Field

[0001] The utility model relates to a high-ring-rigidity hollow-wall tube, in particular to a high-ring-rigidity hollow-wall tube and a processing device thereof. Background Art

[0002] In order to reduce the overall weight of plastic drain pipes, some manufacturers currently open several long through holes around the plastic drain pipes, that is, to form a hollow wall pipe structure, so that the plastic drain pipes around the through holes can form a frame structure, thereby reducing the weight of the material while ensuring the overall external pressure resistance of the pipe. On this basis, conventional plastic drain pipes are processed by extrusion molding, but due to the limitations of the wall thickness of the hollow wall pipe and the extrusion mold molding method, it is difficult for the mold to pull the material during the extrusion molding process so that the material can fully flow to the empty area in the molding cavity; that is, once the wall thickness of the hollow wall pipe is different in different areas, the material in the thinner wall area cannot quickly flow to the thicker wall area after being fully filled, resulting in the hollow wall pipe structure having appearance defects after extrusion and poor yield.

[0003] On the other hand, conventional materials flow horizontally during the extrusion process, causing the materials to accumulate toward the bottom of the cavity under the influence of gravity, further reducing the possibility of the materials flowing to the empty area above the cavity. Under the above process limitations, the current hollow wall tubes are designed to maintain a consistent wall thickness around the through hole to ensure the stability of the tube during extrusion.

[0004] However, the defect of the hollow wall tube structure is that in order to achieve uniform wall thickness of the hollow wall tube, its through hole needs to be designed into a rectangular structure; which makes the through hole have corners after forming, causing the hollow wall tube to be easily deformed and damaged at the corners after being compressed. On this basis, although the manufacturer will set rounded corners around the through hole to alleviate the problem, the deformation resistance of this part will still be weaker than other positions, thereby reducing the overall compressive strength of the hollow wall tube.

[0005] Therefore, the existing hollow wall tube has the problem of low compressive strength. Utility Model Content

[0006] The utility model aims to provide a high ring stiffness hollow wall tube and a processing device thereof, which can improve the compressive strength of the hollow wall tube and ensure the stability of the hollow wall tube during extrusion molding.

[0007] The technical solution of the utility model is: a high ring stiffness hollow wall tube, including a hollow tube body, a plurality of through holes are distributed in a ring shape around the tube wall of the hollow tube body, the cross-sectional shape of the through holes is circular or square, and arc-shaped side walls are formed at both ends of the through holes. The length direction of the through holes is the same as the length direction of the hollow tube body, adjacent through holes are separated from each other, and there is a difference in the thickness of the tube wall of the hollow tube body around the through holes.

[0008] A processing device for a high ring stiffness hollow wall tube based on the above-mentioned method includes an inner mold and an outer mold which are nested inside and outside and coaxially arranged, an extrusion cavity is formed between the inner mold and the outer mold, a feed port and an extrusion port are formed at both ends of the extrusion cavity, the inner mold is connected to the outer mold through a material equalizing portion at one end close to the feed port, a spiral material equalizing groove is provided on the material equalizing portion, a hollow forming mold rod is connected to the side wall of the inner mold at one end close to the extrusion port, and the number of the hollow forming mold rods is multiple and distributed in a ring around the inner mold.

[0009] In the aforementioned processing device, the outer side of the outer mold is rotatably connected to a base, the outside of the outer mold is connected to a driving mechanism, and the inner mold and the outer mold are in a synchronously rotating state relative to the base.

[0010] In the aforementioned processing device, the first flow channel, the second flow channel and the third flow channel are sequentially formed in the extrusion chamber along the flow direction of the material, the width of the first flow channel gradually decreases along the flow direction of the material, the material equalizing portion is located in the first flow channel, the two ends of the material equalizing trough are respectively connected to the feed port and the second flow channel, and the cross-sectional area of ​​the material equalizing trough gradually decreases along the direction of the second flow channel.

[0011] In the aforementioned processing device, the mold cavity volume of the second flow channel is larger than that of the third flow channel.

[0012] In the aforementioned processing device, the end of the inner mold is detachably connected to the inner mold core located in the third flow channel, and a plurality of connection grooves for accommodating the hollow forming mold rod are formed at the connection between the inner mold core and the side wall of the inner mold. A plurality of air inlet grooves for accommodating the hollow forming mold rod are formed at the connection between the inner mold core and the end of the inner mold. One end of the hollow forming mold rod is snapped into the connection groove, and the other end of the hollow forming mold rod extends into the third flow channel through the connection groove.

[0013] In the aforementioned processing device, the end of the inner mold is buckled and connected to the inner mold core via a step groove, and the connecting groove and the air inlet groove are both located in the step groove.

[0014] Compared with the prior art, the utility model has the following characteristics:

[0015] (1) The utility model provides a through hole with an arc-shaped side wall around the tube wall of the hollow tube body, so that the hollow tube body with the through hole structure can effectively eliminate the angular parts around the through hole compared with the existing hollow tube body with a rectangular hole structure, thereby improving the compressive strength of the hollow tube body;

[0016] (2) On this basis, the utility model optimizes the structure of the processing device so that the outer mold and the inner mold can maintain a synchronous rotation state during the extrusion molding process of the hollow tube body, thereby keeping the material in the extrusion cavity flowing along the circumferential direction. On the one hand, the uniformity of the material in different circumferential areas is improved to prevent the material from accumulating at the bottom of the extrusion cavity due to gravity. On the other hand, the material can continue to flow to the gap area during the molding process, that is, to ensure that the material is completely filled, thereby overcoming the structural defects of the hollow tube body after molding and ensuring the extrusion molding stability of the hollow tube body.

[0017] (3) By setting a material balancing groove on the surface of the inner mold, the material can flow to the surrounding of the extrusion cavity after entering, thereby improving the uniformity of the material in the extrusion cavity, and cooperating with the rotation of the mold frame to keep the material in a uniform state when entering the third flow channel, further improving the extrusion molding stability of the hollow tube body;

[0018] (4) Through the connection structure of the hollow forming mold rod, the inner mold and the inner mold core, the inner mold core can also be buckled on the hollow forming mold rod after connection, thereby ensuring the positioning effect and stability of the hollow forming mold rod after installation, and further improving the extrusion molding stability of the hollow tube body;

[0019] Therefore, the utility model can improve the compressive strength of the hollow wall tube and ensure the stability of the hollow wall tube during extrusion molding. BRIEF DESCRIPTION OF THE DRAWINGS

[0020] Figure 1 is a schematic structural diagram of the hollow wall tube in Example 1;

[0021] Figure 2 is a schematic diagram of the structure of the processing device in Example 1;

[0022] Figure 3 yes Figure 2 A-direction sectional view;

[0023] Figure 4 yes Figure 2 A magnified view of point B;

[0024] Figure 5 It is a schematic diagram of the structure of the hollow wall tube in Example 2.

[0025] The markings in the accompanying drawings are: 1-inner mold, 2-outer mold, 3-extrusion cavity, 4-feed port, 5-extrusion port, 6-material equalizing groove, 7-hollow molding mold rod, 8-base, 9-material equalizing part, 10-inner mold core, 11-connecting groove, 12-air inlet groove, 13-step groove, 100-hollow tube body, 200-through hole, 300-side wall, 301-first flow channel, 302-second flow channel, 303-third flow channel. DETAILED DESCRIPTION

[0026] The present invention is further described below in conjunction with the accompanying drawings and embodiments, but they are not intended to limit the present invention.

[0027] Embodiment 1. A high ring stiffness hollow wall tube, comprising: Figure 1 As shown, it includes a hollow tube body 100, the material of the hollow tube body 100 is a polyolefin material, and a plurality of through holes 200 are distributed in a ring shape around the tube wall of the hollow tube body 100. The cross-sectional shape of the through hole 200 is square, and arc-shaped side walls 300 are formed at both ends of the through hole 200. The length direction of the through hole 200 is the same as the length direction of the hollow tube body 100, and adjacent through holes 200 are separated from each other. There is a difference in the thickness of the tube wall of the hollow tube body 100 around the through hole 200.

[0028] Also included is a processing device, which is used to process the hollow wall tube in Example 1; the processing device is composed as follows Figure 2-4 As shown, it includes an inner mold 1 and an outer mold 2 which are nested inside and outside and coaxially arranged, an extrusion cavity 3 is formed between the inner mold 1 and the outer mold 2, a feed port 4 and an extrusion port 5 are formed at both ends of the extrusion cavity 3 respectively, the inner mold 1 is connected to the outer mold 2 via a material equalizing portion 9 at the end near the feed port 4, the inner mold 1 and the outer mold 2 are in a relatively fixed state after being connected via the material equalizing portion 9, a spiral material equalizing groove 6 is provided on the material equalizing portion 9, the inner mold 1 is connected to a hollow forming mold rod 7 on the side wall near the end of the extrusion port 5, and the number of the hollow forming mold rods 7 is plural and distributed around the inner mold 1 in a ring.

[0029] The outer side of the outer mold 2 is rotatably connected to a base 8 , the outside of the outer mold 2 is connected to a driving mechanism, and the inner mold 1 and the outer mold 2 are in a synchronous rotation state relative to the base 8 .

[0030] A first flow channel 301, a second flow channel 302 and a third flow channel 303 are sequentially formed in the extrusion chamber 3 along the flow direction of the material. The width of the first flow channel 301 gradually decreases along the flow direction of the material. The material equalizing portion 9 is located in the first flow channel 301. Both ends of the material equalizing groove 6 are respectively connected to the feed port 4 and the second flow channel 302. The cross-sectional area of ​​the material equalizing groove 6 gradually decreases along the direction of the second flow channel 302.

[0031] The mold cavity volume of the second flow channel 302 is larger than that of the third flow channel 303 .

[0032] The end of the inner mold 1 is detachably connected to an inner mold core 10 located in the third flow channel 303, and a plurality of connecting grooves 11 for accommodating the hollow forming mold rod 7 are formed at the connection between the inner mold core 10 and the side wall of the inner mold 1. A plurality of air inlet grooves 12 for accommodating the hollow forming mold rod 7 are formed at the connection between the inner mold core 10 and the end of the inner mold 1. The connecting grooves 11 and the air inlet grooves 12 are interconnected, one end of the hollow forming mold rod 7 is snapped into and connected to the air inlet groove 12, and the other end of the hollow forming mold rod 7 extends into the third flow channel 303 through the connecting groove 11.

[0033] The end of the inner mold 1 is snap-fitted to the inner mold core 10 via the step groove 13 , and the end of the inner mold core 10 extends to the step groove 13 and is bolted to the inner mold 1 . The connecting groove 11 and the air inlet groove 12 are both located in the step groove 13 .

[0034] In this embodiment, by opening a through hole 200 with an arc-shaped side wall 300 around the hollow tube 100 , the compressive strength of the hollow tube 100 can be improved.

[0035] On this basis, this embodiment further defines a corresponding processing device according to the above-mentioned hollow wall tube, so that it can realize extrusion molding of the hollow wall tube. When in use, the inner mold 1 and the outer mold 2 are in a synchronous rotation state driven by an external driving mechanism; then the material is squeezed in from the feed port 4, and the material enters the first flow channel 301 through the equalizing trough 6 under the action of extrusion. After entering the equalizing trough 6, the material flows in a spiral shape toward the extrusion port 5, so that it is evenly distributed around the extrusion chamber 3 during the flow process, avoiding the accumulation of the material at the bottom of the extrusion chamber 3 under the action of gravity. After flowing out of the equalizing trough 6, the material passes through the second flow channel 302 and the third flow channel 303 in turn, and the rotating inner mold 1 and outer mold 2 are used to pull the material during the flow process, so that the material flows continuously and evenly along the circumference of the extrusion chamber 3.

[0036] When the material enters the third flow channel 303, a cavity corresponding to the hollow wall tube structure can be formed through the outer mold 2, the hollow molding mold rod 7 and the inner mold core 10, so that the material can be extruded and molded after the cavity is completely filled. During the extrusion process of the hollow wall tube, the continuously rotating inner mold 1 and outer mold 2 can pull the material, so that the material flows under the pulling action and fills the gap area of ​​the cavity, thereby improving the molding effect of the hollow wall tube after extrusion. Under the above cooperation, the processing device of the utility model can realize the extrusion molding of hollow wall tubes with a diameter of 90 to 3000 mm, and ensure the product quality of the hollow wall tube after extrusion.

[0037] Embodiment 2. A high ring stiffness hollow wall tube, comprising: Figure 5As shown, it includes a hollow tube body 100, the material of the hollow tube body 100 is polyolefin material, and a plurality of through holes 200 are distributed in a ring shape around the tube wall of the hollow tube body 100. The cross-sectional shape of the through hole 200 is circular, and the length direction of the through hole 200 is the same as the length direction of the hollow tube body 100. Adjacent through holes 200 are separated from each other, and there is a difference in the thickness of the tube wall of the hollow tube body 100 around the through hole 200.

Claims

1. A high ring stiffness hollow wall tube, characterized in that: The invention comprises a hollow tube body (100), wherein a plurality of through holes (200) are distributed in an annular shape around the tube wall of the hollow tube body (100), the cross-sectional shape of the through hole (200) is circular or square, arc-shaped side walls (300) are formed at both ends of the through hole (200), the length direction of the through hole (200) is the same as the length direction of the hollow tube body (100), adjacent through holes (200) are separated from each other, and the tube wall thickness of the hollow tube body (100) around the through hole (200) is different.

2. A processing device for a high ring stiffness hollow wall tube according to claim 1, characterized in that: The invention comprises an inner die (1) and an outer die (2) which are nested inside and outside and arranged coaxially, an extrusion cavity (3) is formed between the inner die (1) and the outer die (2), a feed port (4) and an extrusion port (5) are respectively formed at two ends of the extrusion cavity (3), the inner die (1) is connected to the outer die (2) via a material equalizing portion (9) at one end close to the feed port (4), a spiral material equalizing groove (6) is provided on the material equalizing portion (9), a hollow forming die rod (7) is connected to the side wall of the inner die (1) at one end close to the extrusion port (5), and the number of the hollow forming die rods (7) is plural and distributed in a ring around the inner die (1).

3. The processing device according to claim 2, characterized in that: The outer side of the outer mold (2) is rotatably connected to a base (8), the outside of the outer mold (2) is connected to a driving mechanism, and the inner mold (1) and the outer mold (2) are in a synchronous rotation state relative to the base (8).

4. The processing device according to claim 2, characterized in that: A first flow channel (301), a second flow channel (302) and a third flow channel (303) are sequentially formed in the extrusion chamber (3) along the flow direction of the material. The width of the first flow channel (301) gradually decreases along the flow direction of the material. The material equalizing portion (9) is located in the first flow channel (301). Both ends of the material equalizing groove (6) are respectively connected to the feed port (4) and the second flow channel (302). The cross-sectional area of ​​the material equalizing groove (6) gradually decreases along the direction of the second flow channel (302).

5. The processing device according to claim 4, characterized in that: The mold cavity volume of the second flow channel (302) is greater than that of the third flow channel (303).

6. The processing device according to claim 4, characterized in that: The end of the inner mold (1) is detachably connected to an inner mold core (10) located in the third flow channel (303); a plurality of connection grooves (11) for accommodating a hollow molding mold rod (7) are formed at the connection between the inner mold core (10) and the side wall of the inner mold (1); a plurality of air inlet grooves (12) for accommodating the hollow molding mold rod (7) are formed at the connection between the inner mold core (10) and the end of the inner mold (1); one end of the hollow molding mold rod (7) is snap-fitted and connected in the connection groove (11), and the other end of the hollow molding mold rod (7) extends into the third flow channel (303) through the connection groove (11).

7. The processing device according to claim 6, characterized in that: The end of the inner mold (1) is buckled and connected to the inner mold core (10) via a step groove (13), and the connection groove (11) and the air inlet groove (12) are both located in the step groove (13).

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