JP3070399U - Corrosion prevention structure for fastening plate type pipe joint - Google Patents

Abstract

(57) [Problem] To provide a fastening plate type pipe joint with a simple structure to prevent the occurrence of corrosion between the fastening plate and the pipe. SOLUTION: A fastening plate is slidably fitted to each end of a pair of pipes each having a flange at an end, and both fastening plates are pulled together by a screwing means of a female screw and a male screw, and the pair of tubes are pulled. A fastening plate type pipe joint for connecting pipes, wherein an electrical insulating material is interposed between the fastening plate and the pipe and flange with which the fastening plate comes in contact to electrically shut off the two. Corrosion prevention structure.

Description

[Detailed description of the invention]

[0001]

[Technical field to which the invention belongs]

 According to the present invention, a fastening plate is slidably fitted on each end of a pair of pipes each having a flange at each end, and both fastening plates are drawn by means of a female screw and a male screw. The present invention relates to a structure for preventing corrosion in a fastening plate type pipe joint for connecting a pair of pipes.

[0002]

[Prior art]

 In various types of piping plants that use the above-mentioned fastening plate type pipe joints, since the pipes at the joints are connected so as to be able to conduct electricity using the fastening plate as an energizing medium, a weak current flows through the entire piping. In this case, when a stainless steel tube, which is widely used in various plants, is used, if a different type of metal, such as a cast iron fastening plate, is used, the pipe and the fastening plate may be in contact with different metals. Corrosion occurs due to the weak current flowing there.

Conventionally, as a countermeasure to prevent the above-mentioned corrosion, a method of using a stainless steel fastening plate of the same type as the pipe has been adopted. However, since the fastening plate made of stainless steel is expensive, There was a disadvantage that it was economically disadvantageous.

[0004]

[Problems to be solved by the invention]

 An object of the present invention is to prevent the occurrence of corrosion at a contact portion between a fastening plate and a pipe with a simple structure.

[0005]

[Means for achieving the object]

 In order to achieve the above object, the present invention provides a pair of pipes each having a flange at each end, wherein a fastening plate is slidably fitted on each end of the pair of tubes, and both fastening plates are screwed into a female screw and a male screw. Means for connecting said pair of pipes by means of means, wherein an electrical insulating material is interposed between said fastening plate and said pipe and flange with which it comes in contact to electrically connect them. We propose a corrosion prevention structure for the clamped plate joints that have been shut off.

The “screw means” of the fastening plate type pipe joint according to the present invention includes a nut portion (female screw) provided on one fastening plate and an annular thread portion (male screw) provided on the other fastening plate. It consists of a plurality of bolts and a plurality of nuts that penetrate both fastening plates by pulling both fastening plates together by screwing them together to connect the pair of pipes. One that pulls both fastening plates to connect the pair of pipes, and the like are included. Hereinafter, embodiments of the present invention will be described with reference to the drawings.

[0007]

【Example】

 In FIG. 1, a pair of pipes (1) and (1a) to be connected is made of stainless steel as an example, and flanges (2) and (2a) are protruded from the ends thereof, respectively. At the end of each of the tubes (1) and (1a), a cylindrical electrical insulating material (3) or (3a) made of a flexible sheet such as an ethylene tetrafluoride-based resin or a silicon-based resin is placed. The pipes (1) and (1a) are covered with the insulating materials (3) and (3a) so as to cover the rear surface and the outer peripheral surface of the flanges (2) and (2a) from the outer peripheral surface. Annular fastening plates (4) and (4a) having holes smaller in diameter than the flanges (2) and (2a) are slidably fitted on the wrapped ends. (5) and (5a) are located between the back surfaces of the flanges (2) and (2a) covered with the insulating materials (3) and (3a) and the fastening plates (4) and (4a). Flat washer interposed.

The one fastening plate (4) has a nut portion (6) having an inner diameter larger than that of the flange (2) on the front surface thereof, with the nut portion (6) protruding forward from the flange (2) appropriately. The fastening plate (4) and the nut portion (6) are formed into a hexagonal shape that can be turned and operated by turning the entire outer peripheral surface shape.

The other fastening plate (4a) has the same outer peripheral surface shape as a hexagon, and has an annular screw portion (6a) which can be screwed with the nut portion (6) on the front surface thereof. It protrudes from the flange (2a) as appropriate.

[0010] The flanges (2) and (2a) of the pair of pipes (1) and (1a) as described above are provided with a gasket made of an electrically insulating material such as an ethylene tetrafluoride resin or a silicon resin. 7), and the nut portion (6) of the pair of fastening plates (4) and (4a) and the screw portion (6a) are screwed together in that state. , (4a) are attracted to each other, whereby the two pipes (1) and (1a) are connected in a state where the flanges (2) and (2a) are crimped through the gasket (7).

With the above connection, the pair of fastening plates (4) and (4a) are electrically disconnected from the pipes (1) and (1a) by the electric insulating materials (3) and (3a). This prevents the occurrence of corrosion at the contact portions with the pipes (1) and (1a) and the flanges (2) and (2a).

Further, according to the knowledge of the present inventors, it is recognized that when a weak current flows through the tubes (1) and (1a), corrosion occurs on the inner surfaces of the tubes. However, in the above example, the two pipes (1) and (1a) are electrically disconnected by the electrical insulation material (3) and (3a) and the electrical insulating gasket (7). Therefore, corrosion of the inner surface of the pipe is prevented.

Another embodiment shown in FIG. 2 is a disk-shaped annular fastening plate () at the ends of a pair of tubes (11) and (11a) wrapped with electrical insulation (13) and (13a). 14) and (14a) are slidably fitted, for example, six bolts (16a)... Are passed through both fastening plates (14) and (14a), and nuts (16). The two tubes (11) and (11a) are connected together, and the other structure is substantially the same as that of FIG.

[0014]

[Effect of the invention]

 The corrosion prevention structure of the fastening plate type pipe joint according to the present invention can electrically shut off the fastening plate and the pipe by a simple structure to which an electric insulating material is added. It is possible to prevent the occurrence of corrosion caused by the electric current in the contact portion of the battery. Also, according to the present invention, it is possible to use an inexpensive cast iron fastening plate for a stainless steel pipe joint, which can be economically advantageous.

[Brief description of the drawings]

FIG. 1 is a longitudinal sectional front view of a pipe joint having a corrosion prevention structure according to the present invention in a separated state.

FIG. 2 is a longitudinal sectional front view of a connection state of another embodiment.

[Explanation of symbols]

 1, 1a, 11, 11a Pipe 2, 2a, 12, 12a Flange 3, 3a, 13, 13a Electrical insulating material 4, 4a, 14, 14a Clamping plate 6 Nut 6a Screw 16 Nut 16a Bolt

Claims (1)

[Utility model registration claims] A fastening plate is slidably fitted on each end of a pair of pipes each having a flange at an end, and both fastening plates are drawn by means of a female screw and a male screw. A joint plate type pipe joint for connecting pipes as described above, wherein an electric insulating material is interposed between the clamp plate and the tube and flange with which the clamp plate comes in contact, and the two plates are electrically disconnected from each other. Corrosion prevention structure for joints.