JP2006002864A - Bellows expansion joint made of non-metal material - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a bellows expansion joint made of non-metal material including a fluoro-resin layer in the bellows formed from a film material, capable of equipping it with an enhanced durability by subjecting the film material to a crimping process. <P>SOLUTION: The bellows 3 consist of a laminate of fabric or a composite layered body in which a fluoro-resin layer 31 for keeping air-tightness is interposed, and the film material 31 to form the fluoro-resin layer 31 is subjected to the crimping process (asperity part 311) having asperity on the molding section. The formation of crimping is owing to emboss processing. The preferable film material of the fabric bellows 3 is a PTFE film 31, in which inorganic fiber woven cloths 33-35 of glass cloth etc. are laminated or overlapped on the two surfaces of the film (on the atmospheric side and gas side). There is a case acceptable that the voids 312 with respect to the inorganic fiber woven cloths 33-35 produced due to the asperity 311 (31) are filled with adhesive 4 followed by lamination and adhesion, or the case in which the voids 312 are left without adhesion. <P>COPYRIGHT: (C)2006,JPO&NCIPI

Description

  The present invention includes a pair of flanges that are extendably connected to a connecting portion of a gas turbine exhaust duct, a flue, an airway, and other ducts (or pipes) and that are connected and fixed to opposite pipe ends, This is related to the improvement of non-metallic bellows expansion joints that are made by loosening a non-metallic bellows with a longer width than the separation distance on the outer circumference in the axial direction between the flanges. The present invention relates to a non-metallic bellows expansion joint in which a film material forming a resin layer is subjected to graining to improve durability.

  The non-metallic bellows is typically a fabric bellows, in which inorganic fiber woven fabrics such as glass cloth are laminated or polymerized on both surfaces (atmosphere side and gas side) of a fluororesin layer (for example, PTFE film). It is comprised as a laminated body or a multilayer body. Here, PTFE refers to polytetrafluoroethylene resin (tetrafluoroethylene resin) and is widely distributed as a typical material product of fluororesin.

  Conventionally, this type of bellows has a PTFE film that holds the internal fluid tightly and a woven fabric made of inorganic fibers for heat insulation, and is loosened so that the cross-sectional shape becomes longer than the mounting distance. The connection is fixed.

  However, in use, the PTFE film usually has wrinkles (local bends), and the bellows repeatedly expands and contracts, resulting in uneven deformation of the buttocks and subjecting to stress. There was a problem that internal fluid leaked due to damage. In other words, PTFE film wrinkles reduce the durability (expansion life of expansion and contraction) of bellows (expansion joint).

Among these, in the manufacture of a resin film bonded molded product, there is one that forms a textured transfer surface on a resin film during injection molding. (For example, see Patent Document 1). However, there is no material that has been subjected to a texturing process on the fluororesin layer (PTFE film) of bellows.
JP-A-7-276426

  The problem to be solved is to alleviate the generation of wrinkles in the PTFE film constituting the fluororesin layer when the bellows is attached and during the expansion and contraction operation, and to increase the flexibility when the film is expanded and contracted. Thereby, the improvement (life extension) of the durability (lifetime of expansion and contraction) of the bellows is achieved.

  The present invention has been made in view of such circumstances, eliminates the above-mentioned problem, suppresses the generation of wrinkles during use by applying a texture to the film material constituting the fluororesin layer, and A non-metallic bellows expansion joint having improved durability is provided.

In order to solve the problems, the present invention provides a pair of flanges that are extendably connected to a connecting portion of a pipe line and are connected and fixed to opposite pipe end parts, and are spaced apart from each other on the outer circumference in the axial direction between the flanges. It is an improvement of a non-metallic bellows expansion joint obtained by attaching a slack to a non-metallic bellows having a width longer than the distance,
The non-metallic bellows is made of a laminated body or a multilayer body of a fabric with an airtight holding fluororesin layer interposed therebetween, and the film material forming the fluororesin layer is subjected to embossing in a concavo-convex shape in a sectional view. It is characterized by.

  According to the present invention, it is possible to alleviate the generation of wrinkles on the film material constituting the fluororesin layer when the bellows is attached and when the expansion and contraction operation is performed, and it is possible to increase the flexibility when the bellows is expanded and contracted. Durability (repetitive life of expansion and contraction) can be improved (life extension).

  A non-metallic bellows expansion joint (hereinafter simply referred to as an expansion joint) according to an embodiment of the present invention will be described below with reference to the accompanying drawings.

  FIG. 1 is an external view of an expansion joint.

  FIG. 2 is a detailed explanatory view of a bellows cross section of the expansion joint.

  FIG. 3 is a detailed explanatory view of a bellows section in another example.

  As shown in FIG. 1, the expansion joint X of the present invention is interposed in a gas turbine exhaust duct, a flue, an airway and other pipe connection parts so as to be extendable and contractible, and is connected and fixed to the opposite pipe end parts. A pair of flanges 1; 1 and a non-metallic bellows 3 having a band width longer than the separation distance are attached to the outer periphery in the axial direction between the flanges 1;

  As shown in FIGS. 2 and 3, the non-metallic bellows 3 is composed of a laminate or a multi-layered fabric (same as the fabric bellows) with a fluororesin layer 31 for airtightness interposed therebetween, and the fluorine The film material for forming the resin layer 31 is subjected to a textured process (311) having a concavo-convex shape in a sectional view. The embossing is performed by embossing.

  The optimum fabric bellows 3 is obtained by using a PTFE film 31 as a film material and laminating or polymerizing inorganic fibrous woven fabrics 33 to 35 such as glass cloth on both surfaces (atmosphere side and gas side). In addition, when the adhesive 3 is filled in the gap 312 between the inorganic fibrous woven fabrics 33 to 35 generated in the concavo-convex portion 311 (31) and laminated and bonded [FIG. 2], or when the gap 312 is left unbonded [ Any of FIG. 3] is possible.

  The present invention modifies the laminated (multi-layer) structure of the fabric bellows and improves (extends) the durability (repetitive life) of the expansion joint, which is useful in practice.

It is an external view of an expansion joint. It is a bellows cross-section detailed explanatory drawing of an expansion joint. It is bellows cross-section detailed explanatory drawing in another example.

Explanation of symbols

1 Flange 2 Sleeve 3 Bellows
31 Fluororesin (PTFE is a film)
311 Concavity and convexity (texturing)
312 Air gap
33 heat-resistant glass cloth
34 Weatherproof glass cloth
35 Acid-resistant glass cloth 4 Adhesive 5 Pipe line X Expansion joint

Claims (2)

A pair of flanges that are extendably connected to the connecting portion of the pipe line and are connected and fixed to the opposite pipe end parts, and a non-metal made of a band width longer than the separation distance on the outer periphery in the axial direction between the flanges In a non-metallic bellows expansion joint made by attaching a bellows with a loosened bellows,
The non-metallic bellows is made of a laminated body or a multilayer body of a fabric with an airtight holding fluororesin layer interposed therebetween, and the film material forming the fluororesin layer is subjected to embossing in a concavo-convex shape in a sectional view. A non-metallic bellows expansion joint. The non-metallic bellows expansion joint according to claim 1, wherein the film material is a PTFE film.

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