CN109249601B

CN109249601B - Low-roughness PE-RT pipeline preparation technology

Info

Publication number: CN109249601B
Application number: CN201811068468.9A
Authority: CN
Inventors: 秦杰; 胡正华; 周绍强; 贺成志; 赵银
Original assignee: Chongqing Weixing New Building Materials Co ltd
Current assignee: Chongqing Weixing New Building Materials Co ltd
Priority date: 2018-09-13
Filing date: 2018-09-13
Publication date: 2020-10-02
Anticipated expiration: 2038-09-13
Also published as: CN109249601A

Abstract

The invention relates to the technical field of plastic pipelines, and discloses a preparation technology of a low-roughness PE-RT pipeline, which comprises the following steps: A. preparing an anti-scale material: treating inorganic nanoparticles with a coupling agent, then performing centrifugal separation, drying and grinding, adding a base material, polytetrafluoroethylene micro powder and a processing aid, and stirring and mixing through a material mixing device to obtain a uniform premix; B. preparing a PE-RT pipeline: and (3) extruding the PE-RT raw material by using a double-layer co-extrusion single-screw extruder, wherein the outer pressure-bearing layer is used for extruding the PE-RT raw material, and the inner scale prevention layer is used for extruding the premix to obtain the PE-RT pipeline with a double-layer structure. According to the invention, the scale prevention layer is additionally arranged in the PE-RT pipeline, so that the surface energy and roughness of the inner surface of the PE-RT pipeline are reduced, the adhesion of dirt and impurities is reduced, and the pipeline can be prevented from being blocked.

Description

Low-roughness PE-RT pipeline preparation technology

Technical Field

The invention relates to the technical field of plastic pipelines, in particular to a preparation technology of a low-roughness PE-RT pipeline.

Background

In recent years, the application of the PE-RT pipe in the field of floor heating is becoming more and more extensive, but the PE-RT pipe has the phenomenon that the inner wall of the pipe is scaled after being used for a plurality of heating seasons, the heat exchange efficiency of a system is influenced, and periodic cleaning is needed. The main reasons for the inner wall of the PE-RT pipe are: (1) the ground heating water belongs to circulating use water, and is circulated in a heater, a pipeline and a radiator for a long time, so that sewage is easily formed; (2) the surface energy of the pipeline material is large, oil stains in circulating water are easy to adhere to the surface of the pipeline material, the oil stains further adhere to fine impurities, and finally a dirt layer is formed on the pipeline wall; (3) the roughness of the inner surface of the pipeline is larger, and the deposition speed of dirt is further accelerated. The three reasons seriously affect the heating effect, the light influences the heating effect, and the heavy causes the blockage of the pipeline.

Disclosure of Invention

The invention aims to provide a preparation technology of a low-roughness PE-RT pipeline, which aims to solve the problems of poor heating effect and even pipeline blockage caused by easy scaling of the inner wall of the PE-RT pipeline in the prior art.

In order to achieve the purpose, the technical scheme adopted by the invention is as follows:

a low roughness PE-RT pipeline preparation technology comprises the following steps:

A. preparing an anti-scale material: treating inorganic nanoparticles with a coupling agent, then performing centrifugal separation, drying and grinding, adding a base material, polytetrafluoroethylene micro powder and a processing aid, and stirring and mixing through a material mixing device to obtain a uniform premix;

B. preparing a PE-RT pipeline: and (3) extruding the PE-RT raw material by using a double-layer co-extrusion single-screw extruder, wherein the outer pressure-bearing layer is used for extruding the PE-RT raw material, and the inner scale prevention layer is used for extruding the premix to obtain the PE-RT pipeline with a double-layer structure.

Compared with the prior art, the invention has the following principle and beneficial effects: the coupling agent is used for carrying out surface modification on the nano inorganic particles, so that the agglomeration phenomenon among the nano inorganic particles is reduced, the nano inorganic particles are dispersed more uniformly, and the preparation of the anti-scaling material is facilitated. The anti-scaling layer is arranged in the pipeline, and the polytetrafluoroethylene micro powder is added into the anti-scaling material, so that the inner wall of the anti-scaling layer has very low surface energy, and the effect of preventing oil stains and sludge from being attached to the inner wall of the PE-RT pipeline is achieved, so that the anti-scaling effect is achieved, the pipeline is prevented from being blocked, and the pipeline heating effect is further improved.

Further, the wall thickness of the scale prevention layer of the PE-RT pipeline is 1/8-1/10 of the wall thickness of the bearing layer. When in design, the wall thickness of the anti-scaling layer needs to be as thin as possible, so that the anti-scaling effect is achieved, the overall weight of the pipeline is reduced, and the normal use of the pipeline is not affected.

Further, the core mold and the mouth mold of the double-layer co-extrusion single-screw extruder are treated by Teflon spraying. The core mould and the mouth mould which are sprayed by Teflon can ensure the smoothness of the inner wall of the pipeline to the maximum extent and avoid oil stains and sludge from being attached to the inner wall of the PE-RT pipeline.

Further, the anti-scaling material consists of base material, polytetrafluoroethylene micro powder, nano inorganic particles, coupling agent and processing aid, and the weight percentage of the components is as follows: 70-80% of base material, 5-20% of polytetrafluoroethylene micropowder, 3-5% of nano inorganic particles, 1-1.5% of coupling agent and 2-5% of processing aid.

Further, the base material is a powder base material.

Further, the base material is polyethylene powder base material.

The high-density polyethylene powder base material is adopted, so that the components in the anti-scaling material can be uniformly mixed, the optimal dispersion effect is achieved, and the fusion strength of two layers of interfaces is ensured.

Further, the nano inorganic particles are nano silicon nitride and nano silicon dioxide.

Further, the coupling agent is a silane coupling agent.

Further, the processing aid is a fluoropolymer processing aid. The fluorine-containing polymer processing aid has low solubility in a matrix, and seeps out of the melt to the surface of the melt in the processing process, and because the fluorine-containing polymer processing aid and the metal mouth film wall have low surface energy, and the core mold is treated by Teflon and cannot be adhered to the end part of the outlet core mold, a layer of fluorine-containing polymer precipitation layer can be formed on the inner wall of the PE-RT pipeline when the PE-RT pipeline is prepared; meanwhile, in the process of preparing the anti-scaling material, the fluoropolymer processing aid and the polytetrafluoroethylene micro powder act synergistically to reduce the surface energy of the inner wall of the anti-scaling layer, so that oil stains and sludge can be prevented from being attached to the inner wall of the PE-RT pipeline, and the anti-scaling effect is achieved.

Drawings

FIG. 1 is a schematic structural diagram of a material mixing device according to an embodiment of the present invention;

fig. 2 is an enlarged view of a point a in fig. 1.

Detailed Description

The following is further detailed by way of specific embodiments:

reference numerals in the drawings of the specification include: mixing box 1, (mixing) shaft 2, stirring vane 3, cam 4, first cylinder 5, second cylinder 6, first pipe 7, first check valve 8, first piston 9, second piston 10, first spring 11, second spring 12, first piston rod 13, second piston rod 14, discharge gate 15, baffle 16, first electro-magnet 17, second electro-magnet 18, switch 19, air feed case 20, air guide case 21, turbine 22, venthole 23, through-hole 24, second pipe 25, filter screen 26, third check valve 27.

The embodiment is basically as shown in the attached figures 1 and 2:

a technology for preparing a low-roughness PE-RT pipeline is needed in the process, the material mixing device comprises a rack, a mixing box 1 is fixedly connected to the rack, a stirring shaft 2 is rotatably connected to the mixing box 1, a spiral stirring blade 3 is fixedly connected to one side of the stirring shaft 2 in the mixing box 1, the left end of the stirring shaft 2 penetrates through the side wall of the mixing box 1, a cam 4 is fixedly sleeved on the stirring shaft 2, a first cylinder 5 and a second cylinder 6 are fixedly connected to the rack, a first guide pipe 7 is communicated between the first cylinder 5 and the second cylinder 6, a first one-way valve 8 which is communicated with the second cylinder 6 in a one-way mode is installed on the first guide pipe 7, a second one-way valve (not shown in the figure) which is communicated with the first cylinder 5 and the outside and is communicated with the first cylinder 5 in a one-way mode is installed on the first cylinder 5, an air release valve (not shown in the figure) is installed on the, a first piston 9 is connected in the first cylinder 5 in a sliding manner, a second piston 10 is connected in the second cylinder 6 in a sliding manner, a first spring 11 is welded between the first piston 9 and the wall of the first cylinder 5, a second spring 12 is welded between the second piston 10 and the wall of the second cylinder 6, a first piston rod 13 which is abutted against the cam 4 is fixedly connected on the first piston 9, a second piston rod 14 with adjustable length is fixedly connected on the second piston 10, a discharge port 15 is arranged at the bottom of the mixing box 1, a baffle plate 16 for sealing the discharge port 15 is hinged on the mixing box 1, a torsion spring (not shown in the figure) is welded between the baffle plate 16 and the mixing box 1, a first electromagnet 17 is fixedly connected at the position of the mixing box 1 close to the discharge port 15, a second electromagnet 18 which is repelled from the first electromagnet 17 is fixedly connected in the baffle plate 16, and a switch 19 for opening and closing the first electromagnet 17 and the second electromagnet 18 is, the second piston rod 14 is used for abutting against the switch 19; an air supply box 20 and an air guide box 21 communicated with the air supply box 20 are fixedly connected to the rack, a turbine 22 fixedly sleeved on the stirring shaft 2 is connected in the air guide box 21 in a rotating mode, an air outlet hole 23 is formed in the air guide box 21, a through hole 24 is formed in the bottom of the mixing box 1, a second guide pipe 25 is connected between the air outlet hole 23 and the through hole 24, and a filter screen 26 and a third one-way valve 27 conducting to the mixing box 1 in a one-way mode are installed in the through hole 24; the method comprises the following steps:

A. preparing an anti-scale material: 3-5% of nano inorganic particles (in this embodiment, nano inorganic particles are nano silicon nitride or nano silicon dioxide) are treated with 1-1.5% of silane coupling agent, and then centrifugal separation, drying and grinding are carried out. After the reaction is finished, the mixture of the silane coupling agent and the nano inorganic particles is added into a mixing box 1, and then 70-80% of base material (in the embodiment, the base material is polyethylene powder base material), 5-20% of polytetrafluoroethylene micro powder and 5-20% of processing aid (in the embodiment, the processing aid is fluoropolymer processing aid) are added into the mixing box 1.

Then, the air supply box 20 is started, the air supply box 20 supplies air into the air guide box 21, the air entering the air supply box 20 is discharged from the air outlet 23, so that continuous air flow is formed in the air guide box 21, the air flow is used as driving force to drive the turbine 22 to rotate, the turbine 22 drives the stirring shaft 2 to rotate, the stirring shaft 2 drives the stirring blades 3 to rotate, and all components in the mixing box 1 are stirred to realize uniform mixing; the air in the air guide box 21 is discharged through the air outlet 23 and then enters the mixing box 1 through the second guide pipe 25 and the through hole 24, the air entering the mixing box 1 moves from bottom to top due to low air density and continuous air blowing, and the components are stirred again in the process, so that the uniform mixing effect is achieved, the passing air can be divided by arranging the filter screen 26 at the through hole 24, the air homogenizing effect is achieved, and the air penetrates through the components in the mixing box 1 in the form of bubbles and further stirs the materials; since the third check valve 27 is installed at the through hole 24, the material in the mixing box 1 does not enter the second guide pipe 25 from the through hole 24.

Because the length of the second piston rod 14 is adjustable, the distance between the second piston rod 14 and the switch 19 is adjusted before stirring, so that the second piston rod 14 can be abutted against the switch 19 after stirring for a period of time, and the switch 19 is started. Namely: when the stirring shaft 2 rotates, the cam 4 is driven to rotate, because the first piston rod 13 is abutted against the cam 4, the first piston 9 reciprocates up and down under the action of the first spring 11 and the cam 4, the first piston 9 intermittently inflates the second cylinder 6, the second piston 10 gradually moves upwards and compresses the second spring 12, the second piston 10 drives the second piston rod 14 to move upwards to be close to the switch 19, after the mixing and stirring are completed, a uniform premix, namely an anti-scale material is obtained, the air supply box 20 is closed, the stirring shaft 2 stops rotating, at the moment, the second piston rod 14 is just abutted against the switch 19, the switch 19 is started, the first electromagnet 17 and the second electromagnet 18 are electrified, because the first electromagnet 17 and the second electromagnet 18 repel each other, a repulsive force is generated between the first electromagnet 17 and the second electromagnet 18, and the baffle 16 rotates around the hinge joint in the counterclockwise direction, the torsional spring will take place deformation, makes discharge gate 15 open, and the material in mixing box 1 will be followed discharge gate 15 and emitted, and in-process baffle 16 rotates to certain angle (like 45 degrees) after, will no longer rotate, and the baffle 16 of slope this moment can play the effect of guide, and the material of being convenient for flows, prevents that the material from spraying and causing the waste with the everywhere.

After discharging is finished, the air release valve is opened, air in the second cylinder 6 is discharged, the second spring 12 pushes the second piston 10 to move downwards for resetting, the second piston 10 drives the second piston rod 14 to move downwards to be separated from the switch 19, the switch 19 is closed, the first electromagnet 17 and the second electromagnet 18 are powered off, the repulsive force between the first electromagnet 17 and the second electromagnet 18 disappears, the torsion spring restores to deform, the baffle 16 rotates clockwise to reset, and the discharge hole 15 is sealed again.

B. Preparing a PE-RT pipeline: and (3) using a double-layer co-extrusion single-screw extruder, wherein a core mold and a neck mold of the extruder are subjected to Teflon spraying treatment to reduce adhesion, extruding the PE-RT raw material from the outer pressure bearing layer, and extruding the premix prepared in the step A from the inner scale prevention layer to obtain the PE-RT pipeline with a double-layer structure. The wall thickness of the anti-scaling layer of the PE-RT pipeline is 1/8-1/10 of that of the bearing layer, so that the whole weight of the pipeline is reduced while the anti-scaling effect is achieved, and the normal use of the pipeline is not affected.

The finally prepared PE-RT pipeline has the inner surface water contact angle of 90-110 degrees and the surface oil contact angle of 14-50 degrees, has good hydrophobicity and obvious oleophobicity, prevents oil stains and sludge from being attached and has the effect of scale prevention.

The foregoing is merely an example of the present invention and common general knowledge of known specific structures and features of the embodiments is not described herein in any greater detail. It should be noted that variations and modifications can be made by those skilled in the art without departing from the structure of the present invention. These should also be construed as the scope of the present invention, and they should not be construed as affecting the effectiveness of the practice of the present invention or the applicability of the patent. The scope of the claims of the present application shall be determined by the contents of the claims, and the description of the embodiments and the like in the specification shall be used to explain the contents of the claims.

Claims

1. A low roughness PE-RT pipeline preparation technology is characterized in that: the method comprises the following steps:

A. preparing an anti-scale material: treating inorganic nanoparticles with a coupling agent, then performing centrifugal separation, drying and grinding, adding a base material, polytetrafluoroethylene micro powder and a processing aid, and stirring and mixing through a material mixing device to obtain a uniform premix; the material mixing device comprises a frame, a mixing box is fixedly connected to the frame, a stirring shaft is rotatably connected to the mixing box, a spiral stirring blade is fixedly connected to one side of the stirring shaft, which is positioned in the mixing box, the left end of the stirring shaft penetrates through the side wall of the mixing box, a cam is fixedly connected to the stirring shaft, a first cylinder body and a second cylinder body are fixedly connected to the frame, a first guide pipe is communicated between the first cylinder body and the second cylinder body, a first one-way valve which is communicated with the second cylinder body in a one-way manner is mounted on the first guide pipe, a second one-way valve which is communicated with the first cylinder body and the outside and communicated with the first cylinder body in a one-way manner is mounted on the first cylinder body, an air release valve is mounted on the second cylinder body, a first piston is slidably connected to the first cylinder body, a second piston is slidably connected to the second cylinder body, a first spring is welded between the first piston, a first piston rod which is abutted against the cam is fixedly connected to the first piston, a second piston rod with adjustable length is fixedly connected to the second piston, a discharge port is formed in the bottom of the mixing box, a baffle plate for sealing the discharge port is hinged to the mixing box, a torsion spring is welded between the baffle plate and the mixing box, a first electromagnet is fixedly connected to the position, close to the discharge port, of the mixing box, a second electromagnet which is repulsive to the first electromagnet is fixedly connected to the interior of the baffle plate, a switch for opening and closing the first electromagnet and the second electromagnet is mounted to the mixing box, and the second piston rod is abutted against the switch; the rack is fixedly connected with an air supply box and an air guide box communicated with the air supply box, the air guide box is rotationally connected with a turbine fixedly sleeved on the stirring shaft, the air guide box is provided with an air outlet hole, the bottom of the mixing box is provided with a through hole, a second guide pipe is connected between the air outlet hole and the through hole, and a filter screen and a third one-way valve which is communicated with the mixing box in one way are arranged in the through hole;

2. The preparation technology of the low roughness PE-RT pipeline according to claim 1, characterized in that: the wall thickness of the scale prevention layer of the PE-RT pipeline is 1/8-1/10 of that of the bearing layer.

3. The low roughness PE-RT pipeline preparation technology according to claim 2, characterized in that: the core mold and the mouth mold of the double-layer co-extrusion single-screw extruder are treated by Teflon spraying.

4. The low roughness PE-RT pipeline preparation technology according to claim 3, characterized in that: the scale-proof material consists of base material, polytetrafluoroethylene micro powder, nano inorganic particles, coupling agent and processing aid, and the weight percentage of the components is as follows: 70-80% of base material, 5-20% of polytetrafluoroethylene micropowder, 3-5% of nano inorganic particles, 1-1.5% of coupling agent and 2-5% of processing aid.

5. A low roughness PE-RT pipe preparation technique according to any of claims 1 to 4, characterized in that: the base material is a powder base material.

6. The low roughness PE-RT pipeline preparation technology according to claim 5, characterized in that: the base material is polyethylene powder base material.

7. A low roughness PE-RT pipe preparation technique according to any of claims 1 to 4, characterized in that: the nano inorganic particles are nano silicon nitride and nano silicon dioxide.

8. A low roughness PE-RT pipe preparation technique according to any of claims 1 to 4, characterized in that: the coupling agent is a silane coupling agent.

9. The preparation technology of the low roughness PE-RT pipeline according to claim 4, characterized in that: the processing aid is a fluoropolymer processing aid.