RU2263246C1 - Pipe with inner plastic lining - Google Patents

Abstract

FIELD: construction engineering.

SUBSTANCE: invention is used for protection of pipelines from corrosion. Proposed pipe with inner plastic lining contains protective bushings fitted on ends and secured with pipe. Outer diameter of protective bushing is less than inner diameter of pipe by half of thickness of inner plastic lining. Aluminum foil in multilayers is loosely wound on free end of outer surface of protective bushing.

EFFECT: reduced labor in manufacture of pipes.

2 cl, 1 dwg

Description

The invention relates to the manufacture of pipes with an internal coating and can be used to protect pipelines from internal corrosion in various industries: oil and gas, housing and communal services, coal, etc.

Known pipe with an inner plastic sheath containing concentrically located at the ends of the pipe and fastened with her protective sleeve. The protective sleeves are made of metal with a carbon content not exceeding the carbon content in the pipe metal, and the surface of the sleeves is coated with a tread material, such as zinc or aluminum (RF patent No. 2171945, MKI F 16 L 9/02, filed 04/07/2000) .

The disadvantage of this technical solution is the design complexity and inadequate protection of the plastic sheath during pipe welding, as well as the deformation of the pipe at its end when fitting the protective sleeve.

Known pipe with an inner plastic shell containing concentrically located at the ends of the pipe and fastened with it prefabricated protective sleeve consisting of inner and outer rings. The outer rings are made of multilayer winding, of a thin-walled metal tape coated with a double-sided coating of tread material (RF patent No. 2171946, MKI F 16 L 9/02, claimed 05.26.2000).

The disadvantage of this technical solution is the design complexity and insufficient protection of the plastic sheath when welding pipes.

The closest technical solution adopted for the prototype is a pipe with an inner plastic sheath containing perforated and protective sleeves concentrically located at the ends of the pipe and fastened with it and with each other, with annular gaps filled with fusible material (a. S. USSR No. 1572141, MKI F 16 L 9/02).

The disadvantage of this design is the great complexity of manufacturing a protective and tread sleeve, the low-tech manufacturing of a protective sleeve, since more than 50% of the metal goes into shavings, and the annular external protrusion of the protective sleeve deforms the end of the pipe during pressing.

The proposed pipe with an inner plastic shell, containing protective sleeves concentrically located at the ends of the pipe and fastened with it, differs in that the outer diameter of the protective sleeve is smaller than the inner diameter of the pipe by half the thickness of the inner plastic shell, and it is friable on the free end of the outer surface of the protective sleeve and multi-layer wound aluminum foil.

Making the outer diameter of the protective sleeve smaller than the inner diameter of the pipe by half the thickness of the inner plastic shell allows you to get a more technological design of the protective sleeve with a sufficiently strong connection with the plastic shell, and put a loose, multi-wound winding of aluminum into the resulting gap between the protective sleeve and the pipe foil. During welding, due to the large surface of the loose layers, aluminum foil acts as a radiator, namely it takes a large part of the released heat energy and thereby prevents exposure to the plastic shell, while, compared with the prototype, the design of the entire device is greatly simplified and the manufacturability of the protective bushings.

The drawing shows the proposed design of the pipe with an inner plastic sheath.

In the metal pipe 1, the inner plastic shell 2 and the protective sleeve 3 are concentrically located at the end of the pipe 1. The outer diameter of the protective sleeve 3 is less than the inner diameter of the pipe 1 by half the thickness of the inner plastic shell 2, which allows a gap 4 between them. The outer surface of the protective sleeve 3 is wrapped in multilayer, loose layers, aluminum foil 5 in the gap zone 4, and its outer end 6 is expanded to the size of the inner diameter of the pipe 1.

The pipe is assembled in the following sequence.

An inner plastic shell 2 having the shape of a pipe 1 is introduced into the pipe 1. Inside the ends of the pipe 1, the ends of the plastic shell 2 are removed by the length of the smooth part of the protective sleeve 3. The protective sleeve 3 g is pre-wrapped in loose layers with aluminum foil 5 and installed in the pipe 1 in such a way so that the plastic shell 2 tightly crimped the machined part of the protective sleeve 3, and the flared end 6 reached the stop at the end of the pipe 1, without deforming it. While wrapped with aluminum foil 5, the part of the protective sleeve 3 is located in the gap zone 4. The pipe 1 with the plastic sheath 2 and the protective sleeve 3 are connected by welding, where the end of the pipe 1 and the flared end 6 of the protective sleeve 3 form a single weld. In the welding process due to the large surface, the loose winding of aluminum foil 5 acts as a radiator, namely, it takes up the majority of the generated heat energy, preventing exposure to the plastic shell 2, while the prototype sleeve 3 is significantly improved compared to the prototype and the device design is simplified .

Claims (1)

A pipe with an inner plastic shell containing protective sleeves concentrically located at the ends of the pipe and fastened with it, characterized in that the outer diameter of the protective sleeve is less than the inner diameter of the pipe by half the thickness of the inner plastic shell, and on the free end of the outer surface of the protective sleeve aluminum foil is loosely and multilayer wound.