CN112112000A - Reinforced composite sleeper and preparation method thereof - Google Patents

Abstract

The invention discloses a reinforced composite sleeper and a preparation method thereof. The technical scheme is as follows: a sleeper body made of a composite material is included, and the sleeper body is provided with a plurality of longitudinal ribs, and the longitudinal ribs and the composite material are co-extruded to form a sleeper ontology. The invention utilizes FRP bars or steel bars to enhance the strength of the composite sleeper; the longitudinal bars and the composite material can be co-extruded, thereby improving the preparation efficiency of the composite sleeper.

Description

A kind of reinforced composite sleeper and preparation method thereof

technical field

The invention relates to the technical field of sleepers, in particular to a reinforced composite sleeper and a preparation method thereof.

Background technique

Sleepers are a key component of railway track structures. At present, the most common are wooden sleepers and concrete sleepers. In recent years, composite sleepers have begun to be used in practical engineering. Composite sleepers are mainly made of polyurethane, plastic, rubber, resin and other composite materials as raw materials. Waste plastics can also be used to reduce urban plastic landfills to a certain extent and improve the living environment.

The inventors found that most of the composite sleepers developed so far only have a synthetic matrix or are only reinforced with short fibers, and their mechanical properties are similar to those of wooden sleepers. It has the following shortcomings:

1) The composite sleeper has low strength and high thermal expansion coefficient;

2) The existing construction technology cannot co-extrude the composite material and the steel bar, which leads to the difficulty of reinforcement.

SUMMARY OF THE INVENTION

In view of the deficiencies in the prior art, the purpose of the present invention is to provide a reinforced composite sleeper and a preparation method thereof, which utilizes FRP bars or steel bars to enhance the strength of the composite sleeper; Preparation efficiency.

In order to achieve the above object, the present invention is realized by the following technical solutions:

In a first aspect, an embodiment of the present invention provides a reinforced composite sleeper, including a sleeper body made of a composite material, the sleeper body has several longitudinal ribs inside, and the longitudinal ribs and the composite material are co-extruded to form the sleeper body.

As a further implementation manner, the longitudinal bars are FRP bars or steel bars.

As a further implementation manner, the longitudinal ribs penetrate through the sleeper body.

In the second aspect, the embodiment of the present invention also provides a method for preparing a reinforced composite sleeper, which adopts a cold roof method to prepare a reinforced composite sleeper, and co-extrudes the composite material and the longitudinal ribs.

As a further implementation, including:

Sending the blended, extruded and pelletized composite material into a forming extruder;

Longitudinal ribs are arranged at the head of the forming extruder, and the composite material and the longitudinal ribs are co-extruded;

After that, the reinforced composite sleeper is obtained by mould forming.

As a further implementation method, firstly, each component of the composite material is weighed according to the set ratio, and after pre-mixing, a blending modifier is injected, and the mixture is extruded and granulated.

As a further implementation, the blend extrusion granulation control temperature is 160-195 ℃.

As a further implementation, a steel bar or FRP bar is added at the head of the forming extruder, and the radial direction of the steel bar or FRP bar is perpendicular to the machine head.

As a further implementation, the molding extruder melts and plasticizes the formed pellets and controls the temperature to be 155-200°C.

As a further implementation manner, post-processing is performed on the formed reinforced composite sleeper.

The beneficial effects of the above embodiments of the present invention are as follows:

(1) The composite sleeper of one or more embodiments of the present invention has steel bars or FRP bars inside, which can increase the strength of the composite sleeper and reduce the thermal expansion coefficient;

(2) The longitudinal rib and the composite material of one or more embodiments of the present invention can be co-extruded, which overcomes the difficulty of reinforcing the existing composite sleeper, and can improve the production efficiency of the composite sleeper.

Description of drawings

The accompanying drawings forming a part of the present invention are used to provide further understanding of the present invention, and the exemplary embodiments of the present invention and their descriptions are used to explain the present invention, and do not constitute an improper limitation of the present invention.

1 is a schematic structural diagram of a reinforced composite sleeper according to one or more embodiments of the present invention;

Figure 2 is a flow chart of the preparation of a reinforced composite sleeper according to one or more embodiments of the present invention;

Among them, 1. Composite material, 2. Longitudinal reinforcement.

Detailed ways

It should be noted that the following detailed description is exemplary and intended to provide further explanation of the application. Unless otherwise defined, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art to which this application belongs.

It should be noted that the terminology used herein is for the purpose of describing specific embodiments only, and is not intended to limit the exemplary embodiments according to the present application. As used herein, unless the context clearly dictates otherwise, the singular is intended to include the plural as well, furthermore, it is to be understood that when the terms "comprising" and/or "including" are used in this specification, it indicates that There are features, steps, operations, devices, components and/or combinations thereof.

Terminology explanation part: Terms such as "installation", "connection", "connection", "fixation" in this application should be understood in a broad sense, for example, it can be a fixed connection, a detachable connection, or an integrated; It can be a direct connection, or an indirect connection through an intermediate medium, an internal connection between two elements, or an interaction relationship between two elements. specific meaning.

Fiber-reinforced polymer or Fiber-reinforced plastics (FRP for short) tendons are high-strength linear elastic materials synthesized from two materials, continuous fiber material and base resin. According to the different fiber materials, it can be divided into glass fiber (Glass FRP, GFRP) bars, carbon fiber (Carbon FRP, CFRP) bars, aramid fiber (Aramid FRP, AFRP) bars, basalt fiber (Basalt FRP, BFRP) bars and so on. According to the different forms, it can be divided into bar tendons, bar tendon bundles, strands, ribbon bars, sheet bars, plate bars, mesh bars, etc.

Example 1:

This embodiment provides a reinforced composite sleeper, as shown in Figure 1, including a sleeper body, the sleeper body is composed of a composite material 1 and longitudinal ribs 2, and the longitudinal ribs 2 and the composite material 1 are co-extruded to form a sleeper body.

A plurality of longitudinal ribs 2 parallel to each other are arranged inside the composite material 1 , and are consistent with the longitudinal direction of the composite material 1 . The number of longitudinal ribs 2 is determined according to the requirements of sleeper strength and linear expansion coefficient.

Further, the longitudinal bars 2 run through the sleeper body, and the longitudinal bars are FRP bars or steel bars. The existing composite sleeper has low strength and high thermal expansion coefficient. The FRP reinforced composite sleeper in this embodiment can increase the strength and reduce the thermal expansion coefficient.

Embodiment 2:

This embodiment also provides a preparation method of a reinforced composite sleeper, which adopts a cold roof method to prepare a reinforced composite sleeper, and co-extrudes the composite material and the longitudinal ribs.

Specifically, as shown in Figure 2, the cold top method (cold extrusion method, cold push method) adopts a two-step method to produce composite sleepers by blending and extruding tailings with resins such as PE or recycled plastics.

The components of the composite material are weighed according to the ratio, and the materials are automatically fed into the high-speed mixer (pre-mixing). After pre-mixing, it is transported by a tanker, and is fed into the barrel of the blending and modified extruder by an automatic feeder, and the temperature is controlled at 160-195 ° C through the extruder for blending, extrusion and granulation. In this embodiment, the extruder is a Ф50 flat twin extruder.

Then the formed pellets are sent to the forming extruder, and steel bars or FRP bars are added at the head of the forming extruder, the radial direction of which is perpendicular to the head, and the composite material and the longitudinal bars are co-extruded through the forming extruder. out. Melt plasticization control temperature 155-200 ℃. In this embodiment, the forming extruder is a Ф65 cone double forming extruder or a single-screw extruder with a diameter of 150 mm or more.

Afterwards, the composite sleeper is obtained by shaping with a setting die. According to customer requirements, do the following post-processing on the composite sleeper: such as embossing or hob, so as to increase the friction between the sleeper and the ballast.

After the final inspection, the qualified products are bundled, stacked, packaged, and labeled according to the number of roots and sent to the warehouse.

Further, the composite material raw material formula is:

Recycled high-density polyethylene (HDPE) (preferably daily chemical bottle materials, such as laundry detergent bottles, shower gel bottles, etc.) slices 35-75% (preferably 55%), recycled rubber (such as engineering vehicle tires, etc.) slices 5-35% (preferably 12.5%), glass fiber (glass fiber GF) 5-60% (preferably 12.5%, alkali-free glass fiber), filler (calcium powder, mica powder, etc.) 5-50% (preferably 20%), tailings filler ((red mud, phosphogypsum, iron tailings, etc.) 5-50% (preferably 20%)).

To adjust the process or other properties, polypropylene (PP), low density polyethylene (LDPE), linear low density polyethylene (LLDPE), ethylene vinyl acetate (EVA), polystyrene (PS), polyester can also be added (PET), polyvinyl chloride (PVC), cable sheath, etc. 1-5% (preferably 3%).

Other additives can be added as needed: such as compatibilizers (such as MAH-g-PE, etc.) (0.5-1%), lubricants (such as PE wax, stearic acid) (0.5-1%), anti-ultraviolet agents ( Such as UV531 (0.1%)), antioxidant/antioxidant (such as 168 (0.3%), 1010 (0.2%)), dyeing agent (such as waste rubber cracking carbon black, etc., rutile, etc.) (0.5-1%). In addition, the rubber pyrolysis oil in the tire can be used to improve its anti-aging performance and plasticity, and its addition amount is 0-5%.

In the composite sleeper of this embodiment, the extruded composite material is compounded with steel bars or FRP bars, and the composition of the raw materials used is the same as that described above, and the amount of glass fiber is 5-50%, preferably 20-30%. It is also possible to replace steel bars or FRP bars with other reinforcing materials, such as steel pipes, etc.

The above descriptions are only preferred embodiments of the present application, and are not intended to limit the present application. For those skilled in the art, the present application may have various modifications and changes. Any modification, equivalent replacement, improvement, etc. made within the spirit and principle of this application shall be included within the protection scope of this application.

Claims (10)

1. A reinforced composite sleeper, characterized in that it comprises a sleeper body made of a composite material, the sleeper body has several longitudinal ribs inside, and the longitudinal ribs and the composite material are co-extruded to form the sleeper body. 2 . The reinforced composite sleeper according to claim 1 , wherein the longitudinal bars are FRP bars or steel bars. 3 . 3 . The reinforced composite sleeper according to claim 1 , wherein the longitudinal ribs penetrate through the sleeper body. 4 . 4. A method for preparing a reinforced composite sleeper, characterized in that the reinforced composite sleeper is prepared by a cold top method, and the composite material and the longitudinal ribs are co-extruded. 5. The preparation method of a reinforced composite sleeper according to claim 4, characterized in that, comprising: Sending the blended, extruded and pelletized composite material into a forming extruder; Longitudinal ribs are arranged at the head of the forming extruder, and the composite material and the longitudinal ribs are co-extruded; After that, the reinforced composite sleeper is obtained by mould forming. 6. The preparation method of a reinforced composite sleeper according to claim 5, characterized in that, firstly, each component of the composite material is weighed according to the set ratio, and after premixing, a blending modifier is injected, and after a total of Mixing and extrusion granulation. 7 . The preparation method of a reinforced composite sleeper according to claim 6 , wherein the controlled temperature of the blending, extrusion and granulation is 160-195° C. 8 . 8. the preparation method of a kind of reinforced composite sleeper according to claim 5, it is characterized in that, adding reinforcement bar or FRP bar bar at the head of the forming extruder, and the radial direction of the bar or FRP bar bar is perpendicular to the head . 9. The preparation method of a reinforced composite sleeper according to claim 5 or 8, characterized in that, the temperature controlled by the forming extruder to melt and plasticize the formed particles is 155-200°C. 10 . The preparation method of a reinforced composite sleeper according to claim 5 , wherein the formed reinforced composite sleeper is post-treated. 11 .

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