Mould for preventing out-of-roundness of PO type solid-wall spiral pipe

Abstract

The utility model discloses a mould for preventing out-of-roundness of PO type solid-wall spiral pipes, which comprises a core rod and a rib groove splitter plate arranged on the surface of the core rod. According to the technical scheme, the rib groove is formed in the side, close to the runner face, of the core rod, the rib groove splitter plate is arranged above the core rod rib groove, the rib groove splitter plate covers the rib groove runner extrusion section, and through cooperation of the core rod rib groove and the rib groove splitter plate, the problem that a traditional PO type solid-wall spiral pipe is prone to being oval in pipe forming is solved; the front end and the rear end of the rib groove splitter plate are provided with inclined angles to serve as flow guide sections, material accumulation and coking are prevented, and the problems of coking and scribing in the production process are avoided.

Description

Technical Field

[0001] The utility model relates to the technical field of pipe making moulds, in particular to a mould for preventing PO type solid wall spiral pipes from being out of roundness. Background Art

[0002] Compared with cast iron pipes, PVC water pipes are widely used due to their good corrosion resistance, easy installation, light weight and low price. Conventional solid wall spiral pipes are extruded through the grooves on the mandrel to form pipe ribs. This method is easy to form in the extrusion process because of the small stretch ratio, hard material texture and small shrinkage of the pipe ribs in the commonly used PVC materials.

[0003] Data shows that in PO materials, due to the large stretch ratio and soft texture, during the molding process, the material is subjected to greater force at the rib groove and less force on the flow channel surface. The material in the rib groove will naturally squeeze out of the rib groove, resulting in a reduction in the rib material. In the subsequent molding process, due to the uneven distribution of materials, the pipe is prone to deformation at the rib position, resulting in an elliptical pipe and non-roundness that does not meet the standard.

[0004] Chinese patent document CN202753386U discloses an "extrusion die for a silencer spiral tube". It includes a head body, in which a diverter cone and a collecting cone are arranged, and the diverter cone and the collecting cone are interconnected through a diverter plate, the outer side of the diverter cone is a diverter cavity, and the outer side of the collecting cone is a collecting cavity; a mouth die is installed on the head body, a rotating shaft is installed in the mouth die, and hollow core-pulling strips are arranged on both sides of the rotating shaft, wherein a driving rod is installed in the collecting cone, one side of the driving rod is connected to the rotating shaft, and a gear disk is arranged on the outer surface of the other side; a rod body is installed on the outer wall of the rotating shaft, and a spiral rib groove is provided on the rod body. The above technical scheme lacks mold optimization for PO materials, which is easy to cause non-roundness not meeting the standard. Summary of the invention

[0005] The utility model mainly solves the technical problem that the original technical solution lacks mold optimization for PO-type materials, which easily leads to non-roundness that does not meet the standard. A mold is provided to prevent the non-roundness of PO-type solid-wall spiral tubes. A rib groove is provided on the side of the mandrel close to the flow channel surface, and a rib groove diverter plate is provided above the mandrel rib groove, and the rib groove diverter plate covers the rib groove flow channel extrusion section. Through the cooperation of the mandrel rib groove and the rib groove diverter plate, the problem that the traditional PO-type solid-wall spiral tube is easy to be elliptical is solved, and inclined angles are provided at the front and rear ends of the rib groove diverter plate as guide sections to prevent material accumulation and coking material, and avoid the generation of coking material and marking problems during the production process.

[0006] The above technical problems of the utility model are mainly solved by the following technical solutions: the utility model includes a mandrel and a rib groove diverter plate, and the rib groove diverter plate is arranged on the surface of the mandrel. The problem that the traditional PO type solid wall spiral pipe is easy to be elliptical is solved by the cooperation of the mandrel rib groove and the rib groove diverter plate, and the front and rear ends of the rib groove diverter plate are provided with inclined angles as guide sections to prevent the accumulation of coke and avoid the generation of coke and marking problems during the production process.

[0007] Preferably, the mandrel discharge end is a cylinder, the feed end is a truncated cone, the bottom surface of the truncated cone faces the cylinder, the bottom surface diameter of the truncated cone is close to the cylinder diameter, and the diameter of the connection between the bottom surface of the truncated cone and the cylinder is smaller than the cylinder diameter.

[0008] Preferably, the cylindrical surface of the mandrel is the mandrel flow channel surface, and the mandrel flow channel surface is provided with ribs and grooves. The flow channel surface of the rib-groove manifold should be polished to ensure that it has a lower roughness (Ra<0.4).

[0009] Preferably, the rib groove diverter plate is arranged above the rib groove and along the rib groove direction. The rib groove diverter plate is exposed to the outside, and the parts in contact with the material are rounded to ensure smooth flow of the whole material.

[0010] Preferably, the rib groove includes a rib groove flow channel extrusion section, and the rib groove diverter plate covers the rib groove flow channel extrusion section. The area covered by the rib groove diverter plate should not include the tube rib forming section to prevent affecting the forming of the tube cross section.

[0011] Preferably, one end of the rib groove near the mandrel discharge end is a diversion discharge port, and the other end is a diversion feed port. The height of the rib groove diversion plate above the column surface should be controlled to be less than 2 to 3 mm or consistent with the column surface height, and the diversion plate should have a certain thickness to ensure its strength.

[0012] Preferably, the rib groove diverter plate is fan-shaped, the narrow end of the rib groove diverter plate is connected to the diverter outlet end, and the wide end of the rib groove diverter plate is connected to the diverter inlet. The exposed corners or edges of the rib groove diverter plate should be chamfered to prevent scratches after the product is formed.

[0013] Preferably, the two ends of the rib groove diverter plate arranged along the rib groove direction are respectively provided with inclined angles. The front and rear ends of the rib groove diverter plate are provided with inclined angles as guide sections to prevent the accumulation of coke.

[0014] The beneficial effects of the utility model are as follows: a rib groove is provided on one side of the mandrel close to the flow channel surface, a rib groove diverter plate is provided above the mandrel rib groove, and the rib groove diverter plate covers the rib groove flow channel extrusion section, and the problem of easy elliptical forming of traditional PO type solid wall spiral pipes is solved through the cooperation of the mandrel rib groove and the rib groove diverter plate, and inclined angles are provided at the front and rear ends of the rib groove diverter plate as guide sections to prevent accumulation of coke materials and avoid the generation of coke materials and marking problems during the production process. BRIEF DESCRIPTION OF THE DRAWINGS

[0015] Figure 1 It is a structural schematic diagram of the utility model.

[0016] Figure 2 This utility model Figure 1 A partial enlarged view of area A.

[0017] Figure 3 It is an axial cross-sectional view of the utility model.

[0018] Figure 4 This utility model Figure 3 A partial enlarged view of area B.

[0019] In the figure, 1 is a core rod, 2 is a core rod flow channel surface, 3 is a rib-groove diverter plate, 4 is a rib-groove, 5 is a guide slope, 6 is a diverter feed port, and 7 is a diverter discharge port. DETAILED DESCRIPTION

[0020] The technical solution of the utility model is further specifically described below through embodiments and in conjunction with the accompanying drawings.

[0021] Embodiment: A mold for preventing the PO-type solid wall spiral tube from being out of roundness in this embodiment, such as Figure 1 As shown, it includes a core rod 1 and a rib groove diverter plate 3, and the rib groove diverter plate 3 is arranged on the surface of the core rod 1. Conventional solid wall spiral tubes are extruded through the rib grooves on the core rod to form pipe ribs. In common PVC materials, this method is easy to form during the extrusion process due to the small stretch ratio, hard material texture, small shrinkage rate of pipe ribs. However, in PO materials, due to the large stretch ratio and soft material texture, during the forming process, the material is subjected to large force at the position of the rib groove and small force on the flow channel surface. The material in the rib groove will naturally extrude out of the rib groove, resulting in a reduction in pipe rib material. In the subsequent forming process, due to the uneven distribution of materials, the pipeline is prone to deformation at the position of the pipe ribs, resulting in an elliptical pipeline and non-roundness that does not meet the standard. Through the cooperation of the core rod rib groove 2 and the rib groove diverter plate 3, the problem that the traditional PO solid wall spiral pipe is easy to be elliptical is solved, and the front and rear ends of the rib groove diverter plate 3 are provided with inclined angles as guide sections to prevent material accumulation and coke, and avoid the generation of coke and marking problems during the production process.

[0022] The discharge end of the mandrel 1 is a cylinder, and the feed end is a truncated cone, and the bottom surface of the truncated cone faces the cylinder. The diameter of the bottom surface on the truncated cone is close to the diameter of the cylinder, and the diameter of the connection between the bottom surface on the truncated cone and the cylinder is smaller than the diameter of the cylinder. The cylindrical surface of the mandrel 1 is the mandrel flow surface 4, and the mandrel flow surface 4 is provided with rib grooves 2. The flow surface of the rib groove manifold 3 should be polished to ensure that it has a low roughness (Ra<0.4).

[0023] The rib groove 2 includes a rib groove flow channel extrusion section, and the rib groove diverter plate 3 covers the rib groove flow channel extrusion section. The area covered by the rib groove diverter plate 3 should not include the tube rib forming section to prevent affecting the forming of the tube cross section. Figure 3 As shown, one end of the rib groove near the mandrel discharge end is the diversion outlet 7, and the other end is the diversion feed port 6. After adding the rib groove diverter plate, the materials enter from the diversion feed port 6 and go out from the diversion outlet 7. This structure can ensure that during extrusion molding, the material will not change the flow state due to the size of the pressure, thereby affecting the distribution of the material after the pipe is formed, so that the pipe in this state can maintain the non-roundness of its cross section to meet the standard. The height of the rib groove diverter plate 3 above the surface of the cylinder should be controlled below 2 to 3 mm or consistent with the height of the cylinder surface, and the diverter plate should have a certain thickness to ensure its strength. In the case of no rib groove diverter plate 2, when the material is extruded inside the rib groove, its pressure is significantly greater than the pressure of the material outside the rib groove. Therefore, during the molding process, the material inside the rib groove will run out, resulting in a reduction in the material of the pipe ribs after molding. In the case of a large stretch ratio of the PO type mold, the pipe after molding is more likely to shrink and deform at the pipe rib part, making the pipe elliptical and non-roundness not up to standard.

[0024] like Figure 2 As shown, the rib groove diverter plate 3 is arranged above the rib groove 2 and arranged along the direction of the rib groove 2. The rib groove diverter plate 3 covers the extrusion section of the rib groove flow channel. The area covered by the rib groove diverter plate 3 should not include the tube rib forming section to prevent affecting the forming of the tube cross section. The rib groove diverter plate does not completely cover the rib groove flow channel, and it mainly covers the extrusion section, in order to prevent the diverter plate from affecting the final forming of the tube. At the same time, Figure 2The middle diverter plate is provided with a guide slope 4, wherein the top of the slope retains the sharp angle, and the bottom of the slope is rounded to ensure smooth transition of the material. The rib groove diverter plate 3 is exposed to the outside, and the parts in contact with the material must be rounded to ensure smooth flow of the material as a whole. The rib groove diverter plate 3 is fan-shaped, the narrow end of the rib groove diverter plate 3 is connected to the discharge end of the diverter outlet, and the wide end of the rib groove diverter plate 3 is connected to the diverter feed port. The exposed corners or edges of the rib groove diverter plate 3 should be chamfered to prevent scratches after the product is formed. The two ends of the rib groove diverter plate 3 set along the direction of the rib groove 2 are respectively provided with inclination angles. The front and rear ends of the rib groove diverter plate are provided with inclination angles as a guide section to prevent the accumulation of coke. The height of the rib groove diverter plate 3 above the surface of the column should be controlled below 2 to 3 mm or consistent with the height of the column surface, and the diverter plate should have a certain thickness to ensure its strength. The rib groove manifold has a certain thickness. In order to prevent it from affecting the flow of materials and the subsequent forming of pipes, it is necessary to ensure that the manifold is in a proper position, neither protruding too much from the mandrel flow channel surface nor too deep into the rib groove flow channel. Furthermore, the exposed rib groove manifold and the parts in contact with the materials must be rounded to ensure smooth overall flow of the materials.

[0025] Example

[0026] See also Figures 1 to 4 A mold for preventing PO-type solid-wall spiral pipe from being out of roundness comprises a core rod 1 located in a die and a rib groove diverter plate 2 on the rib groove.

[0027] like Figure 1 As shown, the core rod 1 is provided with 4 rib groove flow channels on the flow channel surface. When the rib groove diverter plate 2 is not placed, the pressure of the material when extruding inside the rib groove is significantly greater than the pressure of the material outside the rib groove. Therefore, during the molding process, the material inside the rib groove will run out, resulting in a reduction in the tube rib material after molding. In the case of a large stretching ratio of a PO-type mold, the formed tube is more likely to shrink and deform at the tube rib part, making the tube elliptical and not round enough.

[0028] like Figure 1 and Figure 2 As shown, the rib groove manifold 3 does not completely cover the rib groove flow channel, and mainly covers the extrusion section, in order to prevent the manifold from affecting the final forming of the pipe. The flow channel surface of the rib groove manifold should be polished to ensure that it has a low roughness (Ra<0.4). At the same time, Figure 2 The middle diverter plate is provided with a guide slope 4, wherein the top of the slope retains a sharp angle and the bottom of the slope is rounded to ensure smooth transition of the material. The exposed corners or edges of the rib groove diverter plate should be chamfered to prevent scratches after the product is formed.

[0029] like Figure 3 , Figure 4As shown, the height of the rib groove diverter plate above the cylinder surface should be controlled below 2 to 3 mm or be consistent with the height of the cylinder surface. After the rib groove diverter plate 3 is installed above the core rod flow channel surface 2, the rib groove diverter plate 3 should remain parallel to the core rod flow channel surface 2 to ensure that the materials enter from the diversion feed port 6 and exit from the diversion outlet 7 respectively, and to ensure that during extrusion molding, the flow state of the materials will not change due to the size of the pressure, thereby affecting the distribution of the materials after the pipe is formed, so that the pipe in this state can maintain the non-roundness of its cross section to meet the standard.

[0030] At the same time, the rib groove manifold should have a certain thickness to ensure its strength. In order to prevent it from affecting the flow of materials and the subsequent forming of pipes, it is necessary to ensure that the manifold is in a suitable position, neither protruding too much from the mandrel flow channel surface nor too deep into the rib groove flow channel. Furthermore, the exposed rib groove manifold and the parts in contact with the material must be rounded to ensure smooth flow of the material as a whole and prevent scratches from being generated after the product is formed, which not only ensures the beauty of the product but also prevents the scratches generated after the product is formed from affecting the strength of the product.

[0031] like Figure 2 and Figure 4 As shown, after adding the rib groove diverter plate, the materials enter from the diverter inlet 6 and exit from the diverter outlet 7. This structure can ensure that during extrusion molding, the material will not change its flow state due to the size of the pressure, thereby affecting the distribution of the material after the pipe is formed. Therefore, the pipe in this state can maintain the non-roundness of its cross section to meet the standard.

[0032] It should be noted that the one manifold in the figure is only for the convenience of showing the structure of the main body. In actual application, the number of rib-groove manifolds should be consistent with the number of rib grooves.

[0033] (1) The problem that traditional PO solid wall spiral pipes are easy to be elliptical when formed is solved; (2) The rib groove diverter plate is integrated with the core rod, saving assembly operation time; (3) The rib groove diverter plate has a guide structure, and no charring and marking problems will be generated during the production process.

[0034] The terms "first", "second", "third", "fourth", etc. (if any) in the specification of the present application and the above-mentioned drawings are used to distinguish similar objects, and are not necessarily used to describe a specific order or sequence. It should be understood that the data used in this way can be interchangeable where appropriate, so that the embodiments of the present application described herein can be implemented in an order other than those illustrated or described herein. In addition, the terms "including" and "having" and any of their variations are intended to cover non-exclusive inclusions, for example, a process, method, system, product or device comprising a series of steps or units is not necessarily limited to those steps or units clearly listed, but may include other steps or units that are not clearly listed or inherent to these processes, methods, products or devices.

[0035] The units described above as separate components may or may not be physically separated, and the components displayed as units may or may not be physical units, that is, they may be located in one place, or they may be distributed on multiple network units. Some or all of the units may be selected according to actual needs to achieve the purpose of the scheme of this embodiment. In addition, the functional units in each embodiment of the present application may be assembled into one processing unit, or each unit may exist physically alone, or two or more units may be assembled into one unit.

[0036] The preferred embodiments of the present invention are described above with reference to the accompanying drawings, but the scope of the rights of the present invention is not limited thereto. Any modification, equivalent substitution and improvement made by a person skilled in the art without departing from the scope and essence of the present invention should be within the scope of the rights of the present invention.

[0037] The specific embodiments described herein are merely examples of the spirit of the present invention. Those skilled in the art may make various modifications or additions to the specific embodiments described or replace them in similar ways, but they will not deviate from the spirit of the present invention or exceed the scope defined by the appended claims.

Claims

1. A mold for preventing the out-of-roundness of PO-type solid wall spiral pipes, characterized in that: It comprises a core rod (1) and a rib groove diverter plate (3), wherein the rib groove diverter plate (3) is arranged on the surface of the core rod (1), the discharge end of the core rod is a cylinder, the cylindrical surface of the core rod is the core rod flow channel surface, the core rod flow channel surface is provided with a rib groove (4), the rib groove diverter plate is arranged above the rib groove and arranged along the rib groove direction, the rib groove comprises a rib groove flow channel extrusion section, and the rib groove diverter plate covers the rib groove flow channel extrusion section.

2. A mold for preventing out-of-roundness of PO-type solid wall spiral pipes according to claim 1, characterized in that: The feeding end of the core rod (1) is a truncated cone, and the bottom surface of the truncated cone faces the cylinder.

3. A mold for preventing out-of-roundness of PO-type solid wall spiral pipes according to claim 2, characterized in that: One end of the rib groove (4) close to the discharge end of the core rod (1) is a diversion discharge port (7), and the other end is a diversion feed port (6).

4. A mold for preventing out-of-roundness of PO-type solid wall spiral pipes according to claim 1, characterized in that: The rib-groove diverter plate (3) is fan-shaped, the narrow end of the rib-groove diverter plate (3) is connected to the discharge end of the diverter discharge port (7), and the wide end of the rib-groove diverter plate (3) is connected to the diverter feed port (6).

5. A mold for preventing out-of-roundness of PO-type solid wall spiral pipes according to claim 4, characterized in that: Both ends of the rib-groove diverter plate (3) arranged along the rib-groove (4) direction are respectively provided with an inclination angle.

6. A mold for preventing out-of-roundness of PO-type solid wall spiral pipes according to claim 2, characterized in that: The diameter of the connection between the bottom surface of the truncated cone and the cylinder is smaller than the diameter of the cylinder.

7. A mold for preventing out-of-roundness of PO-type solid wall spiral pipes according to claim 1, characterized in that: The area covered by the rib-groove splitter does not include the tube rib forming section.

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