Drainage pipe mold
By adding a vortex section structure between the straight section and the compressive section of the drainage pipe mold, the problem of insufficient tensile yield strength of the pipe caused by the existing mold structure is solved, and the effect of improving the yield strength of the pipe is achieved, while reducing production costs and processing cycles.
Patent Information
- Application Number
- CN202421819495.6
- Authority / Receiving Office
- CN · China
- Patent Type
- Utility models(China)
- Current Assignee / Owner
- Filing Date
- 2024-07-30
- Publication Date
- 2025-06-13
- Estimated Expiration
- 2034-07-30
AI Technical Summary
The existing drainage pipe mold structure leads to insufficient tensile yield strength of the pipe. Current solutions such as lengthening the straight section to improve yield strength, which have problems such as affecting production efficiency, reducing the apparent quality of the product, long processing cycles, and increasing mold costs.
The vortex section structure is added between the straight section and the compressed section of the pipe. By setting a vortex transition section between the conical section and the cylindrical section of the mandrel, including the straight section at the rear and the inclined section at the front, and arc chamfering at the junction of the adjacent two sections to enhance the tensile yield strength of the pipe.
By adding the vortex section structure, the tensile yield strength of the Φ50/75 specification PVC-U drainage pipe has been improved, from the original 40~40.5Mpa to 41~42.5Mpa, ensuring product quality and reducing mold modification costs and processing cycle.
Smart Images
Figure CN222972727U_ABST
Abstract
Description
Technical Field
[0001] The utility model relates to a die for drainage pipes. Background Art
[0002] PVC-U pipes are mainly made of sanitary grade polyvinyl chloride (PVC) resin, added with appropriate stabilizers, lubricants, fillers, colorants, etc., and are extruded into shape by a plastic extruder and injection molded by an injection molding machine. Through processes such as cooling, curing, sizing, inspection, and packaging, the production of pipes and pipe fittings is completed. They have excellent physical and chemical properties, are resistant to chemical corrosion, have high impact strength, small fluid resistance, a flow rate 30% higher than that of cast iron pipes of the same diameter, are resistant to aging, have a long service life, and a service life of not less than 50 years, making them an ideal material for building water supply and drainage.
[0003] Currently, the die structure of such drainage pipes is as Figure 1 shown, including a compression section with a conical rear part and a straight section with an annular front part. The defect of this structure is that the tensile yield strength of the pipe is insufficient.
[0004] To solve this problem, the industry mainly increases the die pressure, usually by lengthening the length of the straight section to improve the tensile yield strength of the pipe, as Figure 2 shown, which has problems such as affecting production efficiency, reducing the apparent quality of products, long processing cycles, and increased die costs. Content of the Utility Model
[0005] In view of the above problems, the utility model aims to provide a die for drainage pipes, which improves the tensile yield strength of the pipe by adding an eddy current section structure between the straight section and the compression section of the pipe.
[0006] The technical solution of the utility model is a die for drainage pipes, including an outer die body and a mandrel. The outer die body includes a conical channel at the rear section and a cylindrical channel at the front section. The mandrel includes a conical part at the rear section and a cylindrical part at the front section. A material channel is formed between the mandrel and the outer die body. The feature is that: an eddy current transition section is arranged between the conical part and the cylindrical part on the mandrel. The eddy current transition section includes a straight section at the rear and an inclined section at the front. The straight section is parallel to the axis of the mandrel, and the included angle between the inclined section and the straight section is 4 - 5°. An arc chamfer is made at the junction of adjacent two sections.
[0007] Preferably, the total length of the eddy current transition section occupies 1 / 4 - 1 / 3 of the total length of the conical section.
[0008] Preferably, the total length of the cylindrical part of the mandrel occupies 1 / 3 - 1 / 2 of the total length of the entire mandrel.
[0009] Preferably, the length of the straight section is 5 - 10 mm, and the length of the inclined section is 20 - 25 mm.
[0010] Preferably, the maximum channel gap of the eddy current transition section is 4-5 times the channel gap of the cylindrical section.
[0011] Preferably, the size of the channel between the cylindrical channel and the cylindrical section corresponds to a Φ50 pipe or a Φ75 pipe.
[0012] Preferably, the circular arc chamfer between two adjacent surfaces of the inner side of the outer die body and the outer side of the mandrel is R20.
[0013] The utility model adds an eddy current section structure between the cylindrical section and the conical section of the pipe to improve the tensile yield strength of the pipe. BRIEF DESCRIPTION OF THE DRAWINGS
[0014] Figure 1 is a schematic structural diagram of an existing drainage pipe mold;
[0015] Figure 2 is a schematic structural diagram of the existing drainage pipe mold after lengthening the straight section;
[0016] Figure 3 is a schematic structural diagram of the utility model;
[0017] Figure 4 is another schematic structural diagram of the utility model;
[0018] Wherein: 1 - outer die body; 11 - conical channel; 12 - cylindrical channel; 2 - mandrel; 21 - conical section; 22 - cylindrical section; 23 - eddy current transition section; 231 - straight section; 232 - inclined section; 3 - material channel. DETAILED DESCRIPTION OF THE EMBODIMENTS
[0019] The following will further describe the present utility model in detail with reference to the drawings.
[0020] As Figure 3 and Figure 4 shown, the present utility model provides a drainage pipe mold, including an outer die body 1 and a mandrel 2. The outer die body 1 includes a conical channel 11 at the rear section and a cylindrical channel 12 at the front section. The mandrel 2 includes a conical section 21 at the rear section and a cylindrical section 22 at the front section. A material channel 3 is formed between the mandrel 2 and the outer die body 1. An eddy current transition section 23 is provided between the conical section 21 and the cylindrical section 22 on the mandrel 2. The eddy current transition section 23 includes a straight section 231 at the rear and an inclined section 232 at the front. The straight section 231 is parallel to the axis of the mandrel 2. The included angle between the inclined section 232 and the straight section 231 is 4-5°. An arc chamfer is made at the junction of two adjacent sections.
[0021] On the basis of the above solution, the total length of the eddy current transition section 23 occupies 1 / 4 - 1 / 3 of the total length of the conical section 21.
[0022] In addition, the total length of the cylindrical part 22 of the mandrel 2 occupies 1 / 3 - 1 / 2 of the total length of the entire mandrel 2.
[0023] In addition, the length of the straight section 231 is 5 - 10 mm, and the length of the inclined section 232 is 20 - 25 mm.
[0024] Specifically, the maximum channel gap of the eddy current transition section 23 is 4 - 5 times the channel gap of the cylindrical part 22.
[0025] Specifically, the size of the channel between the cylindrical channel 12 and the cylindrical part 22 corresponds to a Φ50 pipe or a Φ75 pipe.
[0026] Furthermore, the circular arc chamfer between the adjacent two surfaces of the inner side of the outer die body 1 and the outer side of the mandrel 2 is R20.
[0027] After the structure of the mandrel 2 and the outer die body 1 of the present utility model is modified, under the condition of using the same materials and the same production equipment, the tensile yield strength of the Φ50 / 75 specification PVC-U drainage pipe is increased from the original 40 - 40.5 Mpa to 41 - 42.5 Mpa. The product quality is effectively guaranteed, and for some molds, only the mandrel size needs to be modified without remaking, with low cost and short processing cycle.
[0028] The above is only the preferred embodiment of the present utility model, and does not impose any formal restrictions on the utility model. Any simple modification, equivalent change or modification made to the above embodiments based on the technical principle of the present utility model still falls within the scope of the technical solution of the present utility model.
Claims
1. A drainage pipe mold, comprising an outer mold body (1) and a core rod (2), wherein the outer mold body (1) comprises a conical channel (11) at a rear section and a cylindrical channel (12) at a front section, and the core rod (2) comprises a conical portion (21) at a rear section and a cylindrical portion (22) at a front section, and a material channel (3) is formed between the core rod (2) and the outer mold body (1), characterized in that: An eddy current transition section (23) is provided between the conical section (21) and the cylindrical section (22) on the core rod (2), the eddy current transition section (23) comprising a straight section (231) at the rear and an inclined section (232) at the front, the straight section (231) being parallel to the axis of the core rod (2), the angle between the inclined section (232) and the straight section (231) being 4-5 degrees, and a circular chamfer is formed at the intersection of two adjacent sections.
2. A drainage pipe mold according to claim 1, characterized in that: The total length of the eddy current transition section (23) accounts for 1 / 4 to 1 / 3 of the total length of the tapered portion (21).
3. A drainage pipe mold according to claim 1, characterized in that: The total length of the cylindrical portion (22) of the core rod (2) accounts for 1 / 3 to 1 / 2 of the total length of the entire core rod (2).
4. A drainage pipe mold according to claim 1, characterized in that: The length of the straight section (231) is 5-10 mm, and the length of the inclined section (232) is 20-25 mm.
5. The drainage pipe mold according to claim 1, characterized in that: The maximum channel clearance of the eddy current transition section (23) is 4 to 5 times the channel clearance of the cylindrical portion (22).
6. A drainage pipe mold according to claim 1, characterized in that: The dimensions of the passage between the cylindrical passage (12) and the cylindrical portion (22) correspond to a Φ50 tube or a Φ75 tube.
7. A drainage pipe mold according to claim 1, characterized in that: The arc chamfer between two adjacent surfaces of the inner side surface of the outer mold body (1) and the outer side surface of the core rod (2) is R20.