Vacuum sizing extrusion die for large diameter polyethylene pipe with on-line adjustable wall thickness

Abstract

The utility model relates to extruder head extrusion die technical field especially relates to a kind of large-diameter polyethylene pipe vacuum sizing extrusion die with on-line adjustable wall thickness.The utility model discloses: extrusion connecting pipe, die connecting body, horizontal fixed die section, flaring fixed die section, horizontal adjusting die section and flaring adjusting die section;Horizontal fixed die section, flaring fixed die section, horizontal adjusting die section and flaring adjusting die section are sequentially connected together by bolt;Horizontal fixed die section and die connecting body extrusion end are connected by bolt;The input end of die connecting body and the extrusion end of extrusion connecting pipe are fixedly connected by bolt;Extrusion connecting pipe is connected with extruder.The technical scheme of the utility model solves the problems, such as small adjustment amount of pipe diameter or wall thickness, great difficulty in production, adjustment after shutdown cooling, reduced production efficiency, increased production cost and the like of the existing outer protective tube machining equipment in the prior art.

Description

Technical Field

[0001] This utility model relates to the field of extrusion die technology, and in particular to a vacuum sizing extrusion die for large-diameter polyethylene pipes with online adjustable wall thickness. Background Technology

[0002] In large-diameter, thick-walled polyethylene outer sheath pipe vacuum sizing extrusion production lines, the adjustment of wall thickness directly affects cost and product quality. According to the national standard GB / T29047-2021 "High-Density Polyethylene Outer Sheath Pipe Rigid Polyurethane Foam Prefabricated Direct-Buried Insulated Pipes and Fittings," section 5.3.2.9a states that the outer diameter and minimum wall thickness of the outer sheath pipe should meet the requirements specified in Table 4. Meeting the national standard's minimum wall thickness requirement means that, especially for large-diameter outer sheath pipes, the wall thickness can be 2-3 mm or more. With an outer sheath pipe wall thickness of 16 mm, the cost increases by more than 10%, significantly impacting overall cost. Wall thickness below the national standard minimum is considered substandard. Therefore, the technology and process for adjusting the wall thickness of polyethylene outer sheath pipes are particularly important. There are three aspects to adjusting the wall thickness of polyethylene outer sheath pipes: 1. When installing the mold orifice and mandrel, use a feeler gauge to repeatedly measure the circumference of the mold outlet. The higher the accuracy, the more uniform the wall thickness of the produced polyethylene outer sheath.

[0003] 2. During the production process, uneven wall thickness can be adjusted by adjusting the bolts around the mold opening.

[0004] 3. During the production process, the amount of cooling water can be adjusted by regulating the flow rate of the cooling water valves around the sizing sleeve. In this way, the wall thickness can be adjusted by spraying the cooling water around the sizing sleeve.

[0005] During the production of prefabricated direct-buried polyurethane insulated pipes with polyethylene outer protective pipes, adjustments are required each time a pipe diameter or wall thickness is produced. The adjustment method is generally to first use a feeler gauge to evenly adjust the circumference of the mold outlet in a cold state before the mold is installed. If the adjustment is not done well before the mold is installed, it will be difficult to adjust the wall thickness of the polyethylene pipe during production. Fine adjustments can only be made by moving the distance between the sizing box and the mold outlet, or by changing the flow rate of the cooling water sprayed around the inlet of the sizing sleeve. The adjustment is very difficult and not easy to control. If neither of the above two methods can be used to adjust, the machine must be stopped and adjusted after cooling.

[0006] In view of the problems existing in the above-mentioned prior art, it is necessary to study and design a new type of vacuum sizing extrusion die for large-diameter polyethylene pipe with online adjustable wall thickness, so as to overcome the problems existing in the prior art. Summary of the Invention

[0007] The existing outer protective pipe processing equipment mentioned above has technical problems such as small adjustment range and high difficulty in adjusting the pipe diameter or wall thickness during production. For example, adjustment is made after the machine is stopped and cooled, which reduces production efficiency and increases production costs. Therefore, a vacuum sizing extrusion die for large-diameter polyethylene pipe with online adjustable wall thickness is provided.

[0008] The technical means adopted in this utility model are as follows: A vacuum sizing extrusion die for a large-diameter polyethylene pipe with online adjustable wall thickness includes: an extrusion connecting pipe, a die connecting body, a horizontal fixed die section, a flaring fixed die section, a horizontal adjusting die section, and a flaring adjusting die section; Furthermore, the horizontal fixed module section, the flared fixed module section, the horizontal adjusting module section, and the flared adjusting module section are connected together in sequence by bolts; Furthermore, the horizontal fixed die section and the extrusion end of the die connector are connected by bolts; Furthermore, the input end of the mold connector is fixedly connected to the extrusion end of the extrusion connector by bolts; Furthermore, the extrusion connector is connected to the extruder.

[0009] Furthermore, the horizontal fixed module, the flared fixed module, and the horizontal adjusting module are fixedly connected. Furthermore, the fixed connection is a stepped end face, connected with fixing bolts.

[0010] Furthermore, the horizontal fixed mold section consists of a horizontal fixed mold section outer mold and a horizontal fixed mold section core mold. The input ends of both are connected to the base section of the mold connecting body, and the extrusion end is set with a stepped opening. Furthermore, the flaring fixed die section consists of a flaring fixed die section outer die and a flaring fixed die section core die. The input ends of the two are designed to match the stepped opening of the extrusion end of the horizontal fixed die section, and are connected by fixing bolts. The extrusion end is set with a stepped opening. Furthermore, the horizontal adjustment module consists of an outer mold and a core mold. The input ends of both are designed to match the stepped opening of the extrusion end of the flared fixed mold and are connected by fixing bolts. The extrusion end of the core mold of the horizontal adjustment module is set with a stepped opening, and the extrusion end of the outer mold of the horizontal adjustment module is set with an outwardly convex arc surface.

[0011] Furthermore, the horizontal adjustment module and the flared adjustment module are in an adjustable connection form; Furthermore, the adjustable connection is an arc-shaped end face, connected with adjusting bolts.

[0012] Furthermore, the flaring adjustment die section consists of a flaring adjustment die section outer die and a flaring adjustment die section core die; the input end of the flaring adjustment die section core die is designed to match the stepped opening of the extrusion end of the horizontal adjustment die section core die, and is connected by fixing bolts; the input end of the flaring adjustment die section outer die is a concave arc surface that matches the convex arc surface of the extrusion end of the horizontal adjustment die section outer die, and is connected by adjusting bolts.

[0013] Furthermore, an adjustment gap is provided at the assembly point of the outer mold of the flaring adjustment section and the outer mold of the horizontal adjustment section, and the extrusion angle of the outer mold of the flaring adjustment section is adjusted by means of adjusting bolts.

[0014] Furthermore, the flaring adjustment section is a replaceable structure used to adjust the extrusion tube diameter.

[0015] The working process of this utility model is as follows: Polyethylene material is heated to a molten state by the extruder screw and barrel and then enters the inner cavity of the extrusion connecting pipe, then the die connector, and then the spiral channel between the outer die and the core die of the horizontal fixed die section for thorough mixing. The cylinder diameter is then gradually increased along the channel, and finally extruded from the channel between the outer die and the core die of the flaring adjustment die section. The cylinder diameter then rapidly decreases and enters the sizing sleeve of the cooling water tank. The thin-walled polyethylene pipe is adsorbed onto the inner wall of the sizing sleeve by vacuum negative pressure, and then cooled and sizing is achieved by spraying cooling water to form the polyethylene outer protective pipe.

[0016] The adjustment process of this utility model is as follows: When the pipe wall thickness is different and needs to be adjusted, loosen the bolts on one side of the outer mold of the horizontal adjustment module and the outer mold of the flaring adjustment module to a certain extent, and then adjust the bolts on the other side. After adjusting to the required wall thickness, tighten the bolts on the loose side until the overall wall thickness is the same, and then production can continue.

[0017] The adjustment mechanism of this invention can precisely control the thickness difference of the polyethylene outer protective pipe to within 0.1mm, which is far lower than the thinnest wall thickness difference of 0.6mm in existing equipment, and will inevitably save a lot of raw materials.

[0018] Compared with the prior art, the present invention has the following advantages: 1. The vacuum sizing extrusion die for large-diameter polyethylene pipes with online adjustable wall thickness provided by this utility model realizes the requirement of adjusting the wall thickness without stopping the machine; 2. The vacuum sizing extrusion die for large-diameter polyethylene pipes with online adjustable wall thickness provided by this utility model can be adjusted without stopping the machine and can be operated directly, thus improving production efficiency. 3. The vacuum sizing extrusion die for large-diameter polyethylene pipes with online adjustable wall thickness provided by this utility model is simple to adjust and easy to operate; 4. The vacuum sizing extrusion die for large-diameter polyethylene pipes with online adjustable wall thickness provided by this utility model changes the traditional method of adjusting the wall thickness by adjusting the vacuum degree and the cooling water volume around the sizing sleeve, relying on experience. It achieves precise adjustment, controls the wall thickness difference within 0.1mm, and avoids waste of raw materials.

[0019] In summary, the technical solution of this utility model solves the problems of existing outer protective pipe processing equipment having small adjustment range and high difficulty in adjusting pipe diameter or wall thickness during production, such as adjustment after shutdown and cooling, which reduces production efficiency and increases production costs. Attached Figure Description

[0020] To more clearly illustrate the technical solutions in the embodiments of this utility model or the prior art, the drawings used in the description of the embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are some embodiments of this utility model. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0021] Figure 1 This is a schematic diagram of the structure of this utility model; Figure 2 This is an enlarged schematic diagram of part A of the present invention; Figure 3 This is a schematic diagram of the assembly of the present invention with the extrusion equipment.

[0022] In the diagram: 1. Extrusion connecting pipe; 2. Die connector; 3. Horizontal fixed die section; 31. Horizontal fixed die section outer die; 32. Horizontal fixed die section core die; 4. Flaring fixed die section; 41. Flaring fixed die section outer die; 42. Flaring fixed die section core die; 5. Horizontal adjusting die section; 51. Horizontal adjusting die section outer die; 52. Horizontal adjusting die section core die; 6. Flaring adjusting die section; 61. Flaring adjusting die section outer die; 62. Flaring adjusting die section core die. Detailed Implementation

[0023] It should be noted that, where there is no conflict, the embodiments and features in the embodiments of this utility model can be combined with each other. The present utility model will now be described in detail with reference to the accompanying drawings and embodiments.

[0024] To make the objectives, technical solutions, and advantages of the embodiments of this utility model clearer, the technical solutions of the embodiments of this utility model will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of this utility model, and not all embodiments. The following description of at least one exemplary embodiment is merely illustrative and is in no way intended to limit this utility model or its application or use. Based on the embodiments of this utility model, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of this utility model.

[0025] It should be noted that the terminology used herein is for the purpose of describing particular embodiments only and is not intended to limit the exemplary embodiments according to the present invention. As used herein, the singular form is intended to include the plural form as well, unless the context clearly indicates otherwise. Furthermore, it should be understood that when the terms "comprising" and / or "including" are used in this specification, they indicate the presence of features, steps, operations, devices, components, and / or combinations thereof.

[0026] Unless otherwise specifically stated, the relative arrangement, numerical expressions, and values ​​of the components and steps described in these embodiments do not limit the scope of this invention. It should also be understood that, for ease of description, the dimensions of the various parts shown in the drawings are not drawn to actual scale. Techniques, methods, and devices known to those skilled in the art may not be discussed in detail, but where appropriate, such techniques, methods, and devices should be considered part of the specification. In all examples shown and discussed herein, any specific values ​​should be interpreted as merely exemplary and not as limitations. Therefore, other examples of exemplary embodiments may have different values. It should be noted that similar reference numerals and letters in the following figures denote similar items; therefore, once an item is defined in one figure, it need not be further discussed in subsequent figures.

[0027] In the description of this utility model, it should be understood that the orientation or positional relationship indicated by directional terms such as "front, back, up, down, left, right", "horizontal, vertical, horizontal" and "top, bottom" is usually based on the orientation or positional relationship shown in the accompanying drawings, and is only for the convenience of describing this utility model and simplifying the description. Unless otherwise stated, these directional terms do not indicate or imply that the device or element referred to must have a specific orientation or be constructed and operated in a specific orientation, and therefore should not be construed as a limitation on the scope of protection of this utility model. The directional terms "inner" and "outer" refer to the inner and outer contours relative to the outline of each component itself.

[0028] For ease of description, spatial relative terms such as "above," "over," "on the upper surface of," "above," etc., are used herein to describe the spatial positional relationship of a device or feature as shown in the figures to other devices or features. It should be understood that spatial relative terms are intended to encompass different orientations in use or operation besides the orientation of the device as described in the figures. For example, if the device in the figures is inverted, a device described as "above" or "above" other devices or structures would subsequently be positioned as "below" or "under" other devices or structures. Thus, the exemplary term "above" can include both "above" and "below." The device may also be positioned in other different ways, rotated 90 degrees, or in other orientations, and the spatial relative descriptions used herein will be interpreted accordingly.

[0029] Furthermore, it should be noted that the use of terms such as "first" and "second" to define components is merely for the purpose of distinguishing the corresponding components. Unless otherwise stated, the above terms have no special meaning and therefore cannot be construed as limiting the scope of protection of this utility model.

[0030] like Figure 1 As shown, this utility model provides a vacuum sizing extrusion die for a large-diameter polyethylene pipe with online adjustable wall thickness, comprising: an extrusion connecting pipe 1, a die connecting body 2, a horizontal fixed die section 3, a flaring fixed die section 4, a horizontal adjusting die section 5, and a flaring adjusting die section 6; the horizontal fixed die section 3, the flaring fixed die section 4, the horizontal adjusting die section 5, and the flaring adjusting die section 6 are connected together in sequence by bolts; the horizontal fixed die section 3 is connected to the extrusion end of the die connecting body 2 by bolts; the input end of the die connecting body 2 is fixedly connected to the extrusion end of the extrusion connecting pipe 1 by bolts; the extrusion connecting pipe 1 is connected to the extruder.

[0031] The horizontal fixed module section 3, the flared fixed module section 4, and the horizontal adjusting module section 5 are fixed connection types; the fixed connection type is a stepped end face, which is connected with fixing bolts.

[0032] The horizontal fixed mold section 3 consists of an outer mold 31 and a core mold 32. Their input ends are connected to the base section of the mold connector 2, and their extrusion ends are stepped. The flared fixed mold section 4 consists of an outer mold 41 and a core mold 42. Their input ends are designed to match the stepped extrusion end of the horizontal fixed mold section and are connected by fixing bolts. Its extrusion end is also stepped. The horizontal adjusting mold section 5 consists of an outer mold 51 and a core mold 52. Their input ends are designed to match the stepped extrusion end of the flared fixed mold section and are connected by fixing bolts. The extrusion end of the core mold 52 is stepped, and the extrusion end of the outer mold 51 is a convex arc surface.

[0033] The horizontal adjustment module 5 and the flared adjustment module 6 are adjustable; the adjustable connection is an arc-shaped end face, which is connected with adjusting bolts.

[0034] like Figure 1 , 2 As shown, the flaring adjustment section 6 consists of a flaring adjustment section outer mold 61 and a flaring adjustment section core mold 62. The input end of the flaring adjustment section core mold 62 is designed to match the stepped opening of the extrusion end of the horizontal adjustment section core mold 52, and is connected by fixing bolts. The input end of the flaring adjustment section outer mold 61 is a concave arc surface that matches the convex arc surface of the extrusion end of the horizontal adjustment section outer mold 51, and is connected by adjusting bolts.

[0035] like Figure 1 , 2 As shown, an adjustment gap is provided at the assembly point of the outer mold 61 of the flaring adjustment section and the outer mold 51 of the horizontal adjustment section, and the extrusion angle of the outer mold of the flaring adjustment section is adjusted by means of the adjusting bolt.

[0036] The flaring adjustment section 6 is a replaceable structure used to adjust the extrusion tube diameter.

[0037] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of this utility model, and are not intended to limit it. Although the utility model has been described in detail with reference to the foregoing embodiments, those skilled in the art should understand that modifications can still be made to the technical solutions described in the foregoing embodiments, or equivalent substitutions can be made to some or all of the technical features therein. Such modifications or substitutions do not cause the essence of the corresponding technical solutions to deviate from the scope of the technical solutions of the embodiments of this utility model.

Claims

1. A vacuum sizing extrusion die for large-diameter polyethylene pipes with online adjustable wall thickness, characterized in that: The vacuum sizing extrusion die for large-diameter polyethylene pipe with online adjustable wall thickness includes: an extrusion connecting pipe (1), a die connecting body (2), a horizontal fixed die section (3), a flaring fixed die section (4), a horizontal adjusting die section (5), and a flaring adjusting die section (6). The horizontal fixing module (3), the flared fixing module (4), the horizontal adjusting module (5), and the flared adjusting module (6) are connected together in sequence by bolts; The horizontal fixed mold section (3) is connected to the extrusion end of the mold connecting body (2) by bolts; The input end of the mold connector (2) is fixedly connected to the extrusion end of the extrusion connector (1) by bolts; The extrusion connecting pipe (1) is connected to the extruder.

2. The vacuum sizing extrusion die for large-diameter polyethylene pipes with online adjustable wall thickness as described in claim 1, characterized in that: The horizontal fixed module (3), the flared fixed module (4), and the horizontal adjusting module (5) are fixedly connected. The fixed connection is a stepped end face, connected with fixing bolts.

3. The vacuum sizing extrusion die for large-diameter polyethylene pipes with online adjustable wall thickness according to claim 2, characterized in that: The horizontal fixed mold section (3) consists of a horizontal fixed mold section outer mold (31) and a horizontal fixed mold section core mold (32). The input ends of the two are connected to the base section of the mold connecting body (2), and the extrusion end is set with a stepped opening. The flared fixed mold section (4) consists of a flared fixed mold section outer mold (41) and a flared fixed mold section core mold (42). The input ends of the two are designed to match the stepped opening of the extrusion end of the horizontal fixed mold section, and are connected by fixing bolts. The extrusion end is set with a stepped opening. The horizontal adjustment module (5) consists of a horizontal adjustment module outer mold (51) and a horizontal adjustment module core mold (52). The input ends of the two are designed to match the stepped opening of the extrusion end of the flared fixed module and are connected by fixing bolts. The extrusion end of the horizontal adjustment module core mold (52) is set with a stepped opening, and the extrusion end of the horizontal adjustment module outer mold (51) is set with an outward convex arc surface.

4. The vacuum sizing extrusion die for large-diameter polyethylene pipes with online adjustable wall thickness according to claim 1, characterized in that: The horizontal adjustment module (5) and the flared adjustment module (6) are in an adjustable connection form; The adjustable connection is an arc-shaped end face, connected with adjusting bolts.

5. The vacuum sizing extrusion die for large-diameter polyethylene pipes with online adjustable wall thickness according to claim 4, characterized in that: The flaring adjustment section (6) consists of a flaring adjustment section outer mold (61) and a flaring adjustment section core mold (62). The input end of the flaring adjustment section core mold (62) is designed to match the stepped opening of the extrusion end of the horizontal adjustment section core mold (52) and is connected by fixing bolts. The input end of the flaring adjustment section outer mold (61) is a concave arc surface that matches the convex arc surface of the extrusion end of the horizontal adjustment section outer mold (51) and is connected by adjusting bolts.

6. The vacuum sizing extrusion die for large-diameter polyethylene pipes with online adjustable wall thickness according to claim 5, characterized in that: The outer mold (61) of the flaring adjustment section and the outer mold (51) of the horizontal adjustment section are provided with an adjustment gap, and the extrusion angle of the outer mold of the flaring adjustment section is adjusted by means of the adjusting bolt.

7. The vacuum sizing extrusion die for large-diameter polyethylene pipes with online adjustable wall thickness according to claim 1, characterized in that: The flaring adjustment section (6) is a replaceable structure used to adjust the extrusion tube diameter.

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