RU138768U1 - COUPLING AND INTERIOR FLANGE - Google Patents

Abstract

1. A flange with a pipe and an inner coating, comprising a flange, a pipe, a weld and an inner coating, characterized in that the inner surfaces of the end of the flange, the weld of the flange with the pipe and part of the pipe without coating are clad with a shell made of corrosion-resistant steel. 2. The flange according to claim 1, characterized in that the inner end of the shell of corrosion-resistant steel is glued to the inner coating of the flange with the pipe using sealant.

Description

The utility model relates to the manufacture of fittings with an internal coating that can be used in the construction of pipelines in various industries for the transportation of aggressive media, for example, the oil, gas, chemical, oil refining industries and housing and communal services.

A utility model is known: Combined flange, characterized in that the shaped profile of the housing with a central passage hole, two opposed projections with conical surfaces with generators located at an acute angle to the axis of the flange, containing an annular protrusion with holes of a combined flange containing an annular protrusion with an end made with the possibility of rigid connection with a sleeve of a ring shape, with a bevel at the end with an inner and outer coating. (RF patent for utility model No. 59191, IPC F16L 3/02 “Combined flange”, by application No. 2006103809/22, 02/08/2006, published on 12/10/2006.

This utility model has the following disadvantages. Very low reliability of corrosion protection for welds of flanged pipe joints. That is, in the transition with welded nozzles, protected from internal corrosion, the bottleneck is the welds of the nozzles with a flange. Stripping welds is a very time-consuming process and requires special equipment to remove the internal burr forming during electric arc welding. In this case, the uniformity of the internal coating in the flange is not ensured due to the remaining sharp edges in the welds, which is the reason for the welded joints of the nozzles with the flange to exit during the operation of the pipeline. In addition, the flange itself with welded nozzles is intended for connection with the help of liners, which are very complex and time-consuming to manufacture and very inconvenient to install. The above design of welded joints during the operation of oil field pipelines showed very low reliability. The pipeline cross section decreases by a large amount, and especially on pipelines with a diameter of 89 mm or less. The decrease in the cross section of the pipeline in the places where the bushings are installed is almost 50%. On large-diameter pipelines and on high-pressure high-pressure water conduits of the reservoir pressure maintenance system, they are simply disrupted by the flow of transported oil or field wastewater.

The technical task of the utility model is to increase the reliability of corrosion protection of welded joints of nozzles with a flange, as well as their welded joints with pipes of the linear part of the pipeline during operation.

The problem is achieved in that in a flange with a pipe and an inner coating, including a flange, a pipe, a weld and an inner coating, where new is that the inner surfaces of the end of the flange, the weld of the flange with the pipe and parts of the pipe without coating are clad with a corrosion-resistant shell become. In the flange, the inner end of the shell made of corrosion-resistant steel is glued to the inner coating of the flange with the nozzle using sealant.

This design of the flange with the pipe and the inner coating allows to increase the reliability of corrosion protection of the welded joint of the pipe with the flange, as well as their welded connection to the pipes of the linear part of the pipeline during operation. Cladding from the inside of the inner surface of the end of the flange, the weld of the flange with the nozzle and part of the nozzle without coating the shell of the stainless steel pipe and their weld with the flange of the stainless steel allows you to further protect the weld from internal corrosion. A weld seam protected from corrosion by an internal coating is covered by a shell made of corrosion-resistant steel, and gluing the inner end of the shell made of corrosion-resistant steel to the inner coating of the flange with pipe using sealant allows reliable sealing to prevent the transported medium from entering the weld of the flange with pipe.

The utility model is illustrated in the drawing. The figure shows a flange with a pipe and an inner coating, consisting of a flange 1, a pipe 2, a weld 3, an inner coating 4, a sealant 5, and a shell 6 made of corrosion-resistant steel.

The assembly of the flange with the pipe and the inner coating is carried out in the following sequence. An electric arc welding to the flange 1 welds the nozzle 2 with the formation of the weld 3. Remove the inner fillet in the weld 3, clean the inner surface of the flange 1 with the welded nozzle 2 using a shot blasting machine and apply the inner coating 4 to the surface of the flange 1, weld 3 and parts branch pipe 2. Branch pipe 2 is left unprotected over the heat propagation length of the weld, at which destruction of the material of the inner coating can occur 4. Apply sealant 5 to the inner coating 4 and install a shell 6 of corrosion non-resistant steel by distributing in the radial direction, in which the entire gap between the inner surfaces of the end of the flange 1, the weld 2 of the flange 1 with the pipe 3 and part of the pipe 2 without coating 4 is selected. Moreover, the shell 6 made of corrosion-resistant steel is glued to the inner surface of the end of the flange 1, weld 2 of flange 1 with pipe 3 and parts of pipe 2 without coating 4 with sealant 5, which allows reliable sealing and to prevent the transported medium from getting to welds 3 of flange 1 with pipes 2.

During installation, a flange with a pipe and an inner coating is connected to the pipes of the linear part of the pipeline by electric arc welding, where a bimetal underlay is installed between the end of the flange with the pipe and the end of the pipe of the linear part of the pipeline. Where the protruding ends of their shells of stainless steel are glued with mastic or sealant to the shells of stainless steel flange with pipe and pipe end. An annular protrusion on the outer surface of the bimetal underlay sleeve is welded to the weld seam of the pipe flange and pipe of the linear part of the pipeline.

Using this design of a flange with a pipe and an inner coating increases the reliability of corrosion protection of welded joints of the pipe with the flange, as well as their welded connection with pipes of the linear part of the pipeline during operation.

References:

RF patent for utility model No. 59191, IPC F16L 3/02 “Combined flange”, by application No. 2006103809/22, 02/08/2006, published on December 10, 2006.

Claims (2)

1. A flange with a pipe and an inner coating, including a flange, a pipe, a weld and an inner coating, characterized in that the inner surfaces of the end of the flange, the weld of the flange with the pipe and part of the pipe without coating are clad with a shell made of corrosion-resistant steel. 2. The flange according to claim 1, characterized in that the inner end of the shell of corrosion-resistant steel is glued to the inner coating of the flange with the pipe using sealant.

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