CN202708482U - Prefabricated directly-buried heat insulation pipe coated joint - Google Patents

Abstract

The utility model relates to the technical field of thermal insulation pipes, in particular to a prefabricated direct-buried thermal insulation pipe repair joint, which includes a steel pipe, a thermal insulation layer, and an outer protective tube. The outer surface of the end of the outer protective tube is provided with an electric melting sleeve. The electric heating sleeve is covered with a heat shrinkable tape. A viscoelastic paste and a viscoelastic tape are arranged sequentially between the electric heating sleeve and the heat shrinkable tape. The utility model has a simple structure, adopts liquefied gas flame to heat the heat-shrinkable tape, and seals the overlapping joint of the polyethylene outer protective tube and the electric heating sleeve through the heat-shrinkable tape to realize flexible connection, which not only ensures the tightness and waterproofness of the joint , and can absorb the axial displacement of the pipeline.

Description

Prefabricated direct buried insulation pipe joint joint

technical field

The utility model relates to the technical field of thermal insulation pipes, in particular to a prefabricated directly buried thermal insulation pipe patch joint.

Background technique

Prefabricated direct-buried thermal insulation pipes are mainly used for district heating external network pipelines. With the promotion of central heating in the country, its consumption is increasing and its application range is becoming wider and wider. Prefabricated directly buried thermal insulation pipeline has many advantages such as waterproof, good anti-corrosion performance, saving investment, shortening construction period, and low maintenance cost. the

The currently used prefabricated direct buried pipes are composed of steel pipes, brackets, insulation layers, and protective layers. According to the design and customer requirements, spiral welded seamless pipes and straight seam pipes are generally used. After the surface of the steel pipe is treated by the advanced shot blasting derusting process, the derusting grade of the steel pipe can reach the Sa2 level in the GB8923-1988 standard, and the surface roughness can reach R=12.5 microns in the GB6060.5-88 standard. The insulation layer is formed by injecting rigid polyurethane foam stock solution into the cavity formed between the steel pipe and the outer sheath with a high-pressure foaming machine at one time. It is commonly known as "tube-in-tube foaming process". Its function is to keep warm, to be waterproof, and to support the self-weight of the heating network. When the temperature of the input medium is: -50°C-120°C, use rigid polyurethane foam as the insulation layer; when the temperature of the conveying medium is: 50°C-150°C, use rigid polyurethane foam Do insulation. The protective layer is prefabricated black plastic pipe with a certain wall thickness, which is ready for use after corona treatment. One of its functions is to protect the insulation layer from being damaged by mechanical hard objects, and the other is to prevent corrosion and waterproof.

The installation of prefabricated direct-buried thermal insulation pipes on-site joints is usually installed in the form of electric hot-melt joints. Protect the outer tube and apply some pressure to make it blend together. The disadvantage of this method is that the aging resistance is poor, and the insulation layer will seep into moisture after cracking, which will corrode the steel pipe and affect the insulation effect.

Utility model content

The purpose of this utility model is to overcome the deficiencies of the above-mentioned technologies, and provide a prefabricated direct-buried thermal insulation pipe joint joint, which has a simple structure and is corrosion-resistant.

In order to achieve the above object, the utility model adopts the following technical scheme: a prefabricated directly buried thermal insulation pipe joint joint, including a steel pipe, a thermal insulation layer, and an outer protective tube, and is characterized in that: the outer surface of the end of the outer protective tube is provided with There is an electric heating sleeve, and the outer sleeve of the electric heating sleeve is connected with a heat shrinkable tape.

A viscoelastic paste and a viscoelastic tape are arranged sequentially between the electric heating sleeve and the heat shrinkable tape.

The beneficial effects of the utility model are: the utility model is simple in structure, adopts the liquefied gas flame to heat the heat-shrinkable belt, and seals the overlap joint between the polyethylene outer protective tube and the electric heating sleeve through the heat-shrinkable belt, realizing flexible connection, ensuring It not only ensures the tightness and waterproofness of the joint, but also absorbs the axial displacement of the pipeline.

Description of drawings

Fig. 1 is a structural representation of the utility model.

Detailed ways

The specific implementation of the utility model will be described in detail below in conjunction with the accompanying drawings and preferred embodiments. As shown in Figure 1: a prefabricated directly buried thermal insulation pipe joint joint, including a steel pipe 1, an insulation layer 2, and an outer protective tube 3, the outer surface of the end of the outer protective tube is provided with an electric melting sleeve 4, so The heat-shrinkable tape 5 is connected outside the electric heating sleeve. A viscoelastic paste 6 (not shown in the figure) and a viscoelastic tape 7 (not shown in the figure) are provided in sequence between the electric heating sleeve and the heat shrinkable tape.

The utility model has a simple structure, adopts liquefied gas flame to heat the heat-shrinkable tape, and seals the overlapping joint of the polyethylene outer protective tube and the electric heating sleeve through the heat-shrinkable tape to realize flexible connection, which not only ensures the tightness and waterproofness of the joint , and can absorb the axial displacement of the pipeline.

The above is only a preferred embodiment of the utility model, it should be pointed out that for those of ordinary skill in the art, without departing from the principle of the utility model, some improvements and modifications can also be made, these improvements and Retouching should also be regarded as the scope of protection of the present utility model.

Claims (2)

1. A prefabricated direct-buried insulation pipe joint joint, comprising a steel pipe, an insulation layer, and an outer protection pipe, characterized in that: the outer surface of the end of the outer protection pipe is provided with an electric heating sleeve, and the electric heating sleeve The outer sleeve of the tube is spliced with a heat shrinkable tape. 2. The prefabricated direct-buried thermal insulation pipe joint joint according to claim 1, characterized in that: viscoelastic paste and viscoelastic tape are sequentially arranged between the electrothermal melting sleeve and the heat shrinkable tape.

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