A peel strength press mold for plastic-lined composite pipe with continuously adjustable diameter and ovality
By designing a peel strength mold for plastic-lined composite pipes with continuously adjustable diameter and ellipticity, the problem of requiring preparation of multiple specifications for traditional molds is solved, simplifying the operation of the mold and saving materials. It is suitable for the acceptance of steel-plastic composite pipes of various specifications.
Patent Information
- Authority / Receiving Office
- CN · China
- Patent Type
- Utility models(China)
- Current Assignee / Owner
- 马鞍山市产品质量监督检验所
- Filing Date
- 2025-07-30
- Publication Date
- 2026-07-21
AI Technical Summary
Traditional steel-plastic composite pipe peel strength test molds require preparation of various specifications, resulting in material waste and inconvenience in operation. Furthermore, the diameter and ellipticity cannot be adjusted, making it difficult to effectively conduct performance acceptance in the laboratory.
Design a peel strength mold for plastic-lined composite pipe with continuously adjustable diameter and ellipticity. The mold consists of an upper coiled steel strip, a lower coiled steel strip, and a centrally placed coiled steel strip. The diameter and ellipticity can be continuously adjusted by adjusting the structural rods and constraints. It is fixed by thin spring steel strips and adhesive tape.
It achieves continuous adjustment of mold diameter and ellipticity, reduces waste of mold types and materials, simplifies test operations, reduces costs, and is suitable for acceptance testing of various specifications of steel-plastic composite pipes.
Smart Images
Figure CN224526425U_ABST
Abstract
Description
Technical Field
[0001] This utility model relates to the field of composite pipe peel strength test mold technology, specifically a plastic-lined composite pipe peel strength test mold with continuously adjustable diameter and ellipticity. Background Technology
[0002] Traditional steel-plastic composite pipe peel strength test molds are solid steel cylinder molds with steps, which are heavy and have no adjustable diameter or ellipticity.
[0003] Figure 1 The schematic diagram of the compression mold for the traditional steel-plastic composite pipe peel strength test is taken from page 12 of GB / T 28897-2021.
[0004] Disadvantages of traditional steel-plastic composite pipe peel strength test molding molds:
[0005] For each type of DN diameter steel-plastic composite pipe, there are many different wall thicknesses for the base pipe, and the polyethylene layer attached to the base pipe is very thin. As a result, even for the same type of DN diameter pipe, each wall thickness requires the preparation of many different specifications of solid steel cylindrical peel strength test molds.
[0006] Another more troublesome reality is that actual pipes cannot be perfectly round; they all have a slight ellipticity. To cope with this reality, the traditional pressing molds, which are already numerous under the copper standard, need to be multiplied by a grade number to handle different ellipticities.
[0007] Taking the DN50 diameter in GB / T 28897-2021 as an example, the common outer diameter is 54mm. According to pages 4 to 7 of GB / T17395-2024, the wall thickness of this base pipe is available in 30 different types: 1.0, 1.2, 1.4, 1.5, 1.6, 1.8, 2.0, 2.2, 2.4, 2.5, 2.8, 3.0, 3.2, 3.5, 3.8, 4.0, 4.3, 4.5, 4.8, 5.0, 5.5, 6.0, 6.5, 7.0, 7.5, 8.0, 8.5, 9.0, 9.5, and 10. Even if only three different levels of ovality are tested using traditional test molds, this specification still requires 30 × 3 = 90 types of traditional test molds. Preparing multiple types of molds is extremely wasteful of steel.
[0008] This is the fundamental reason why the performance acceptance test of steel pipes cannot be effectively carried out in most cases nationwide. A single specification requires an extremely large number of traditional test molds, which almost no laboratory can afford. Table 1 of GB / T 28897-2021 lists 18 common specifications for plastic-lined composite pipes: DN15, 20, 25, 32, 40, 50, 65, 80, 100, 125, 150, 200, 250, 300, 350, 400, 450, and 500. Based on the above estimate, approximately 90 × 18 = 1620 traditional solid cylindrical steel molds would be needed, which almost no laboratory can afford. Furthermore, the weight of large-diameter test molds is extremely high; for example, a single DN500 mold weighs over 200 kg.
[0009] Reference CN221405348U describes a testing platform for the bonding strength of steel-plastic composite pipe inner lining, but it still uses a block-shaped upper mold, which cannot solve the above problems.
[0010] Overall, the traditional steel-plastic composite pipe peel strength test molding method is extremely inconvenient to operate, wastes a lot of steel, and is very costly.
[0011] To address these issues, we provide a peel strength mold for lined composite pipes with continuously adjustable diameter and ellipticity. Utility Model Content
[0012] The purpose of this invention is to overcome the shortcomings of the existing technology and provide a peel strength mold for plastic-lined composite pipes with continuously adjustable diameter and ellipticity, so as to solve the technical problem that traditional experiments require the preparation of various types of molds, resulting in a complicated and redundant preparation process and material waste.
[0013] To solve the above-mentioned technical problems, this utility model provides the following technical solution:
[0014] A peel strength mold for lined composite pipes with continuously adjustable diameter and ellipticity, comprising:
[0015] Upper coiled steel strip;
[0016] The lower coiled steel strip; the upper and lower coiled steel strips are in a ring shape and are set with the same diameter;
[0017] The centrally located coiled steel strip is situated between the upper and lower coiled steel strips. The outer diameter of the centrally located coiled steel strip is matched with the inner diameter of the upper coiled steel strip, and it abuts against the inner walls of the upper and lower coiled steel strips.
[0018] An adjusting structure rod is installed in the middle of the centrally located coiled steel strip, with both ends abutting against the inner wall of the centrally located coiled steel strip; the adjusting structure rod is used to adjust the ellipticity of the centrally located coiled steel strip.
[0019] Constraints are installed on the upper coiled steel strip, the lower coiled steel strip, and the middle coiled steel strip to keep the diameter constant.
[0020] In a further technical solution, the outer diameter of the lower coiled steel strip is not greater than the inner diameter of the sample base tube, but is greater than the inner diameter of the sample inner lining plastic layer.
[0021] In a further technical solution, the constraint element is an adhesive tape, which is used to wrap around the upper coiled steel strip, the lower coiled steel strip, and the middle coiled steel strip respectively.
[0022] In a further technical solution, the upper coiled steel strip, the lower coiled steel strip, and the middle coiled steel strip are all coiled multiple times, and the adhesive tape is radially bonded to the upper coiled steel strip, the lower coiled steel strip, and the middle coiled steel strip.
[0023] In a further technical solution, the adjusting structure rod includes a main rod, with threaded portions on both sides of the main rod. An extension rod is threadedly connected to the threaded portion, and a round abutment is provided at the end of the extension rod away from the main rod. The round abutment is used to abut against the inner wall of the centrally located coiled steel strip.
[0024] In a further technical solution, a small-diameter rod is coaxially fixed on the threaded part, and a round abutment is provided at the end of the small-diameter rod away from the threaded part. The round abutment is used to abut against the inner wall of the centrally placed coiled steel strip.
[0025] The extended rod has an internal threaded cavity, and the small-diameter rod is used to insert into the internal threaded cavity.
[0026] In a further technical solution, a fixing plate is installed on the inner side of the inner end of the centrally placed coiled steel strip, and a positioning hole is provided on the fixing plate;
[0027] A set of extension rods is provided with a stepped surface, which is located between the round abutment and the extension rod; an annular plate is installed outside the stepped surface, and a connecting bearing is installed between the annular plate and the stepped surface; a plug-in post is provided on the annular plate, which is used to insert into the positioning hole.
[0028] Compared with existing technologies, it has the following advantages:
[0029] This invention utilizes a thin spring steel strip material, allowing for continuous and adjustable diameter adjustment and fixation. Diameter adjustment involves first fixing one end, then rotating the spring steel strip clockwise or counterclockwise to achieve continuous diameter adjustment, followed by fixation with a constraint. Ovality is continuously adjustable via a threaded extension rod, allowing for fine-tuning or large-amplitude adjustments.
[0030] To ensure that the installation position is located in the middle of the centrally placed coiled steel strip, this application adds a fixing plate and installs a rotatable annular plate on the extension rod. The spiral adjustment on the threaded part of the extension rod ensures the lateral position, while the rotation of the annular plate with the connecting bearing ensures that the plug can be inserted into the positioning hole, thereby determining the vertical position of the centrally placed coiled steel strip and ensuring the effect of actual contact adjustment of ellipticity. Attached Figure Description
[0031] Figure 1 This is a schematic diagram of a traditional peel strength test for steel-plastic composite pipes in the prior art;
[0032] Figure 2 This is a schematic diagram of the peel strength molding structure of the plastic composite pipe of this utility model. Figure 1 ;
[0033] Figure 3 This is a schematic diagram of the upper coiled steel strip of this utility model;
[0034] Figure 4 This is a schematic diagram of the test where the mold of this utility model is placed on the sample base tube;
[0035] Figure 5 This is a schematic diagram of the adjusting structure rod of this utility model. Figure 1 ;
[0036] Figure 6 This is a schematic diagram of the main rod and the threaded parts at both ends of this utility model.
[0037] Figure 7 This is a schematic diagram illustrating the adjustment and changes of the centrally located coiled steel strip of this utility model;
[0038] Figure 8 This is a schematic diagram showing the increased diameter of the upper coiled steel strip in this utility model;
[0039] Figure 9 This is a schematic diagram of the peel strength molding structure of the plastic composite pipe of this utility model. Figure 2 ;
[0040] Figure 10 This is a schematic diagram of the adjusting structure rod of this utility model. Figure 2 ;
[0041] Figure 11 A cross-sectional view of the extension rod of this utility model. Figure 1 ;
[0042] Figure 12 This is a schematic diagram of the peel strength molding structure of the plastic composite pipe of this utility model. Figure 3 ;
[0043] Figure 13 for Figure 12Enlarged view of part A;
[0044] Figure 14 A cross-sectional view of the extension rod of this utility model. Figure 2 ;
[0045] In the picture:
[0046] 1. Upper coiled steel strip; 2. Lower coiled steel strip; 3. Centrally placed coiled steel strip; 4. Adjusting structural rod; 5. Constraint components;
[0047] 41. Main rod; 42. Threaded section; 43. Extension rod; 44. Round abutment one; 45. Small diameter rod; 46. Round abutment two; 47. Internal threaded cavity;
[0048] 48. Fixing plate; 49. Positioning hole; 410. Annular plate; 411. Connecting bearing; 412. Insertion post; 100. Sample base tube; 200. Sample inner plastic lining layer. Detailed Implementation
[0049] The technical solutions of the present utility model will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of the present utility model, and not all embodiments. Based on the embodiments of the present utility model, all other embodiments obtained by those of ordinary skill in the art without creative effort are within the protection scope of the present utility model.
[0050] like Figure 1 This is a schematic diagram of a traditional peel strength test for steel-plastic composite pipes. The mold is a solid steel cylinder with steps; it is heavy, and its diameter and ellipticity cannot be adjusted.
[0051] Example 1
[0052] Please see Figure 2-8 The present invention provides a technical solution for peel strength molding of plastic-lined composite pipe with continuously adjustable diameter and ellipticity, comprising:
[0053] Upper coiled steel strip 1, such as Figure 3 As shown, a multi-turn heat exchange is set for the thin coiled steel strip, and it is bound with a constraint to constrain the diameter of the coiled steel strip 1. The coiled steel strip is a thin spring steel strip, and the adjustment method is similar to adjusting the outer diameter of a clockwork. It is bound with a constraint to ensure that the coiled steel strip with a variable outer diameter will not continue to return to its original state, whether the outer diameter increases or decreases.
[0054] The lower coiled steel strip 2; the upper coiled steel strip 1 and the lower coiled steel strip 2 are in the shape of a ring and are set with the same diameter; the lower coiled steel strip 2 is the same as the upper coiled steel strip, and the material and constraint method are the same.
[0055] The centrally located coiled steel strip 3 is situated between the upper coiled steel strip 1 and the lower coiled steel strip 2. The outer diameter of the centrally located coiled steel strip 3 is matched with the inner diameter of the upper coiled steel strip 1, and it abuts against the inner side of the inner wall of the upper coiled steel strip 1 and the lower coiled steel strip 2.
[0056] The adjusting structure rod 4 is installed in the middle of the centrally placed coiled steel strip 3, and its two ends abut against the inner wall of the centrally placed coiled steel strip 3; the adjusting structure rod 4 is used to adjust the ellipticity of the centrally placed coiled steel strip 3.
[0057] Constraints 5 are installed on the upper coiled steel strip 1, the lower coiled steel strip 2, and the middle coiled steel strip 3. The constraints 5 are used to keep the diameter constant. The constraints can adopt various structures, such as fixing clips, magnetic structures, adhesives, etc. This application adopts an adhesive method. This method is relatively easy to obtain materials in the laboratory and can be quickly implemented, which helps to ensure the practicality of adjustment and manufacturing.
[0058] See Figure 4 This is a schematic diagram of the peel strength test for the steel-plastic composite pipe of this application. The outer diameter of the lower coiled steel strip 2 is no greater than the inner diameter of the sample base pipe 100, and greater than the inner diameter of the sample inner plastic lining layer 200. The constraint member 5 is adhesive tape, which is used to wrap around the upper coiled steel strip 1, the lower coiled steel strip 2, and the middle coiled steel strip 3 respectively. The adhesive tape can be either transparent or surface-coated. The adhesive tape is relatively thin and does not affect the actual experimental results.
[0059] The upper coiled steel strip 1, the lower coiled steel strip 2, and the middle coiled steel strip 3 are all coiled multiple times. The adhesive tape is radially bonded to the upper coiled steel strip 1, the lower coiled steel strip 2, and the middle coiled steel strip 3. The bonding direction ensures the connection effect of the multiple coiled steel strips, and the radial bonding ensures that adjacent steel strips are bonded to each other on the surface.
[0060] See Figure 5 and Figure 6 The adjusting structure rod 4 includes a main rod 41, and threaded portions 42 are provided on both sides of the main rod 41. An extension rod 43 is threadedly connected to the threaded portion 42. A round abutment 44 is provided at the end of the extension rod 43 away from the main rod 41. The round abutment 44 is used to abut against the inner wall of the centrally placed coiled steel strip 3.
[0061] When a change in diameter (or outer diameter) is required, refer to [reference needed]. Figure 8 As shown, manually remove the original constraints, press down one end, and adjust the diameter by first fixing one end and then rotating the spring steel strip clockwise or counterclockwise, ensuring that its outer diameter is between the outer and inner diameters of the sample's inner plastic lining layer; after adjustment, use adhesive tape to bond it. The diameter adjustment is done in a similar manner to rotating a spring, achieving continuous diameter adjustment by rotating the spring steel strip clockwise or counterclockwise.
[0062] When variable ellipticity is required, refer to Figure 7 As shown, the extension rod on the main adjusting rod, due to the threaded connection ensuring the support effect after adjustment, can squeeze the centrally coiled steel strip to both sides.
[0063] Although the coiled steel strip in this application is a thin steel strip material, its strength meets the requirements for practical use. This application has also been used confidentially in the applicant's experiments.
[0064] Example 2
[0065] See appendix Figure 9-11 As shown, another embodiment of the present invention is provided. Based on embodiment 1, a small diameter rod 45 is coaxially fixed on the threaded part 42. A round abutment 46 is provided at the end of the small diameter rod 45 away from the threaded part 42. The round abutment 46 is used to abut against the inner wall of the centrally placed coiled steel strip 3.
[0066] The extended rod 43 has an internal threaded cavity 47, and the small diameter rod 45 is used to insert into the internal threaded cavity 47.
[0067] This application changes the structure of the adjusting rod 4. The small diameter rod is fixed to the end of the threaded part. During adjustment, only the position of the extension rod on the other side needs to be adjusted to complete the adjustment.
[0068] Example 3
[0069] See appendix Figure 12-14 As shown, another embodiment of the present invention is provided. Based on embodiment 2, a fixing plate 48 is installed on the inner side of the inner end of the centrally placed coiled steel strip 3, and a positioning hole 49 is provided on the fixing plate 48.
[0070] like Figure 13 and 14 An extension rod 43 is provided with a stepped surface, which is located between the round abutment 44 and the extension rod 43; an annular plate 410 is installed outside the stepped surface, and a connecting bearing 411 is installed between the annular plate 410 and the stepped surface; a plug-in post 412 is provided on the annular plate 410, which is used to insert into the positioning hole 49.
[0071] To ensure that the installation position is located in the middle of the centrally placed coiled steel strip, this application adds a fixing plate and installs a rotatable annular plate on the extension rod. The spiral adjustment on the threaded part of the extension rod ensures the lateral position, while the rotation of the annular plate with the connecting bearing ensures that the plug can be inserted into the positioning hole, thereby determining the vertical position of the centrally placed coiled steel strip and ensuring the effect of actual contact adjustment of ellipticity.
[0072] It will be apparent to those skilled in the art that this invention is not limited to the details of the exemplary embodiments described above, and that it can be implemented in other specific forms without departing from the spirit or essential characteristics of this invention. Therefore, the embodiments should be considered exemplary and non-limiting in all respects, and the scope of this invention is defined by the appended claims rather than the foregoing description. Thus, it is intended that all variations falling within the meaning and scope of equivalents of the claims be included within this invention.
Claims
1. A peel strength mold for lined composite pipes with continuously adjustable diameter and ellipticity, characterized in that, include: Upper coiled steel strip (1); The lower coiled steel strip (2) is annular and has the same diameter. The upper coiled steel strip (1) and the lower coiled steel strip (2) are annular. The middle coiled steel strip (3) is located between the upper coiled steel strip (1) and the lower coiled steel strip (2); the outer diameter of the middle coiled steel strip (3) is matched with the inner diameter of the upper coiled steel strip (1) and abuts against the inner side of the inner wall of the upper coiled steel strip (1) and the lower coiled steel strip (2); An adjusting structure rod (4) is installed in the middle of the centrally placed coiled steel strip (3), and both ends abut against the inner wall of the centrally placed coiled steel strip (3); the adjusting structure rod (4) is used to adjust the ellipticity of the centrally placed coiled steel strip (3); Constraints (5) are installed on the upper coiled steel strip (1), the lower coiled steel strip (2) and the middle coiled steel strip (3). The constraints (5) are used to keep the diameter unchanged.
2. The peel strength mold for a plastic-lined composite pipe with continuously adjustable diameter and ellipticity according to claim 1, characterized in that, The outer diameter of the lower coiled steel strip (2) is not greater than the inner diameter of the sample base tube (100), but is greater than the inner diameter of the sample inner plastic lining layer (200).
3. The peel strength mold for a plastic-lined composite pipe with continuously adjustable diameter and ellipticity according to claim 1, characterized in that, The constraint member (5) is an adhesive tape, which is used to wrap around the upper coiled steel strip (1), the lower coiled steel strip (2) and the middle coiled steel strip (3) respectively.
4. The peel strength mold for a plastic-lined composite pipe with continuously adjustable diameter and ellipticity according to claim 3, characterized in that, The upper coiled steel strip (1), the lower coiled steel strip (2), and the middle coiled steel strip (3) are all coiled multiple times, and the adhesive tape is radially bonded to the upper coiled steel strip (1), the lower coiled steel strip (2), and the middle coiled steel strip (3).
5. The peel strength mold for a plastic-lined composite pipe with continuously adjustable diameter and ellipticity according to claim 3, characterized in that, The adjusting structure rod (4) includes a main rod (41), and threaded portions (42) are provided on both sides of the main rod (41). An extension rod (43) is threadedly connected to the threaded portion (42). A round abutment (44) is provided at the end of the extension rod (43) away from the main rod (41). The round abutment (44) is used to abut against the inner wall of the centrally placed coiled steel strip (3).
6. The peel strength mold for a plastic-lined composite pipe with continuously adjustable diameter and ellipticity according to claim 5, characterized in that, A small diameter rod (45) is coaxially fixed on the threaded part (42). A round abutment (46) is provided at the end of the small diameter rod (45) away from the threaded part (42). The round abutment (46) is used to abut against the inner wall of the centrally placed coiled steel strip (3). The extended rod (43) has an internal threaded cavity (47), and the small diameter rod (45) is used to insert into the internal threaded cavity (47).
7. The peel strength mold for a plastic-lined composite pipe with continuously adjustable diameter and ellipticity according to claim 5, characterized in that, A fixing plate (48) is installed on the inner side of the inner end of the centrally placed coiled steel strip (3), and a positioning hole (49) is provided on the fixing plate (48); An extension rod (43) is provided with a stepped surface, which is located between the round abutment (44) and the extension rod (43); an annular plate (410) is installed outside the stepped surface, and a connecting bearing (411) is installed between the annular plate (410) and the stepped surface; a plug-in post (412) is provided on the annular plate (410), which is used to insert into the positioning hole (49).