Preparation method and device of high performance polymers pipes

A technology for high-performance polymers and pipes, which is applied in the field of preparation methods and processing devices for realizing the method, can solve the problems of reducing the circumferential strength of pipes, internal stress defects, and different crystallization degrees of materials, and achieves improved performance and reduced internal stress. Effect

Active Publication Date: 2009-01-07
SICHUAN UNIV
View PDF2 Cites 36 Cited by
  • Summary
  • Abstract
  • Description
  • Claims
  • Application Information

AI Technical Summary

Problems solved by technology

[0002] Conventional plastic extruded pipes have the following problems in the process of processing: (1) The melt flow through the shunt shuttle will produce weld marks, which will reduce the hoop strength of the pipe; (2) Due to the axial (extrusion direction) tension during processing stretching, the polymer macromolecules are oriented along the axial direction, and the crystallization is orderly, so that the axial strength of the pipe exceeds the hoop strength, but in actual use, the hoop force of the pipe is more than 2 times that of the axial direction, which cannot meet the use requirements; (3 ) is cooled by spraying on the outer wall, which makes the inner and outer walls of the pipe uneven in temperature and temperature, and the crystallization degree of the material is different. There are internal stress defects, resulting in low mechanical properties of the pipe, which greatly limits the application as a plastic pressure pipe.
However, there are still some problems in the above technology: (1) because th

Method used

the structure of the environmentally friendly knitted fabric provided by the present invention; figure 2 Flow chart of the yarn wrapping machine for environmentally friendly knitted fabrics and storage devices; image 3 Is the parameter map of the yarn covering machine
View more

Image

Smart Image Click on the blue labels to locate them in the text.
Viewing Examples
Smart Image
  • Preparation method and device of high performance polymers pipes
  • Preparation method and device of high performance polymers pipes
  • Preparation method and device of high performance polymers pipes

Examples

Experimental program
Comparison scheme
Effect test

Example Embodiment

[0029] Example 1

[0030] Such as figure 1 As shown, the device designed by the method of the present invention includes an extruder, a pipe extrusion head, a cooling setting mechanism 16, a pipe tractor 18, a cutting machine 19, a driving mechanism, and a cooling medium conveying mechanism 15 connected in sequence.

[0031] The extruder can be a single-screw or twin-screw extruder. The pipe extrusion head is composed of a head body 1, a front support body 2, a rear support body 3, a pipe extrusion die 4, a lead joint 5, a core rod 6, a bearing 7, 8, 10 and a bearing seat 11. Covered with temperature control heating ring. The head body 1 is a cavity with open ends, and a bearing 7 is placed on the stepped step at the rear end, and the rear support 3 is fixed in it. The front support body 2 is provided with a stepped through hole in the axial direction, in which a bearing 8 is placed, and the pipe extrusion die 4 is supported by it, and is connected to the driving mechanism throug...

Example Embodiment

[0033] Example 2:

[0034] Such as figure 2 As shown, the device of this embodiment designed by the method of the present invention also includes an extruder, a pipe extrusion head, a cooling setting mechanism 16, a pipe tractor 18, a cutting machine 19, a driving mechanism, and a cooling medium conveying mechanism 15 connected in sequence.

[0035] Since the cooling medium delivery mechanism 15 of this embodiment is composed of a micro high-pressure water pump 20, a water storage tank 21 and a nozzle 22, the nozzle 22 is installed at the outlet end of the core rod cooling medium channel 14 and the sizing sleeve 17 in the cooling setting mechanism 16. Except for the technical features that the opening angle of the bell mouth is 5° and the length is 30 cm, the shape, structure and connection relationship of the other parts are completely the same as those of the first embodiment, so the description is omitted.

Example Embodiment

[0036] Example 3

[0037] In this embodiment, high-density polyethylene is used as the raw material for the extruded pipe. figure 1 In the device given, the opening angle of the sizing sleeve of the cooling setting mechanism is 4°, and the length is 40cm. Vacuum sizing and spraying on the outer wall of the pipe are used. The outer wall of the pipe is sprayed at a temperature of 20℃ and passes through the mandrel at the same time. The inner cooling medium channel is fed with air at a temperature of 20°C and a pressure of 0.3 MPa, the circumferential tensile strength of the prepared pipe is 45.6 MPa, and the crack growth length of the pipe after the 300-hour environmental stress cracking performance test is 8.9 mm.

the structure of the environmentally friendly knitted fabric provided by the present invention; figure 2 Flow chart of the yarn wrapping machine for environmentally friendly knitted fabrics and storage devices; image 3 Is the parameter map of the yarn covering machine
Login to view more

PUM

PropertyMeasurementUnit
Hoop tensile strengthaaaaaaaaaa
Hoop tensile strengthaaaaaaaaaa
Hoop tensile strengthaaaaaaaaaa
Login to view more

Abstract

The invention discloses a method for preparing a high-performance polymer pipe. The method adopts the steps that during the extrusion molding process of the pipe, the crystallization, the orientation or the dispersed phase morphological structure of the polymer pipe can be adjusted, controlled and fixed through the shearing action generated by the rotation of a core rod in a machine head relative to an orifice die, or the rotation of the orifice die in the machine head relative to the core rod, or the rotation of the core rod and the orifice die in the identical or opposite direction simultaneously, and by cooling and shaping the inner wall and the outer wall of the extruded pipe simultaneously, and adjusting and controlling the temperature field, the cooling rate and the temperature gradient during the extrusion molding process of the pipe. The invention further discloses a device designed according to the method. The method has the advantages that the macromolecular orientation, the crystallization or the dispersed phase morphological structure which are generated through induction can be retained in the plastic pipe, so that deorientation can be avoided, the internal stress of the pipe can be reduced, and the performance of the pipe is improved.

Description

technical field [0001] The invention belongs to the technical field of polymer pipe processing methods and equipment, and in particular relates to a preparation method of high-performance polymer pipes and a processing device for realizing the method. Background technique [0002] Conventional plastic extruded pipes have the following problems in the process of processing: (1) The melt flow through the shunt shuttle will produce weld marks, which will reduce the hoop strength of the pipe; (2) Due to the axial (extrusion direction) tension during processing stretching, the polymer macromolecules are oriented along the axial direction, and the crystallization is orderly, so that the axial strength of the pipe exceeds the hoop strength, but in actual use, the hoop force of the pipe is more than 2 times that of the axial direction, which cannot meet the use requirements; (3 ) is cooled by spraying on the outer wall, which makes the inner and outer walls of the pipe uneven in tem...

Claims

the structure of the environmentally friendly knitted fabric provided by the present invention; figure 2 Flow chart of the yarn wrapping machine for environmentally friendly knitted fabrics and storage devices; image 3 Is the parameter map of the yarn covering machine
Login to view more

Application Information

Patent Timeline
no application Login to view more
IPC IPC(8): B29C47/00B29C47/78B29C47/92B29C47/08B29C47/88B29C48/09B29C48/90B29C48/92
CPCB29C47/92B29C48/92B29C2948/92704B29C48/09B29C48/832B29C48/90B29C48/908B29C2948/92514B29C2948/92895B29C2948/92904
Inventor 王琪张杰郭岳白时兵华正坤
Owner SICHUAN UNIV
Who we serve
  • R&D Engineer
  • R&D Manager
  • IP Professional
Why Eureka
  • Industry Leading Data Capabilities
  • Powerful AI technology
  • Patent DNA Extraction
Social media
Try Eureka
PatSnap group products