JP2003287160A - Lined pipe member and its joint structure - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a lined pipe member, and a joint structure for dispensing with a gasket, allowing fastening by small fastening force, and suitably usable at high temperatures in the lined pipe member suitable for a pipe passage of a corrosive fluid and a pollution disliking fluid. <P>SOLUTION: When covering an inner peripheral surface of a metallic pipe part 22a and a surface of a metallic collar part 32 connected to an end surface of this pipe part 22a over the whole surface with a fluororesin, the inner peripheral surface of the pipe part 22a is lined with a cylindrical inside layer 26 formed of the fluororesin. A ring-shaped plate body 32 formed of the fluororesin is arranged on the surface of the collar part 22a, and an abutting part of this ring-shaped plate body 32 and the cylindrical inside layer 26 is integrally welded by the fluororesin, and a recessed-projecting seal surface is arranged in the collar part. <P>COPYRIGHT: (C)2004,JPO

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a lined piping member and a joint structure, and more particularly, to a lined piping member suitable for use in a piping path for chemicals and a joint structure thereof.

[0002]

2. Description of the Related Art Generally, medicine, food, semiconductor, chemical industry,
For pipes that handle corrosive fluids and fluids that dislike contamination in other industries, and pipes that are used at high temperatures, the lining structure made of ordinary plastic resin cannot withstand use, and it is necessary to line the inner surface of the pipe with fluororesin. was there. In such a piping line, various joint members such as a straight pipe, a 90 ° elbow, a 45 ° elbow, a tee with the same diameter, a concentric reducer, and a flexible hose are used in addition to a lined steel pipe. Each of these members has a flange portion at the end, and the flange portions of the other members are abutted against this flange portion, and they are connected by clamping with a clamp joint.

FIG. 4 shows a straight tubular short tube 2 as an example of a piping member lined with a fluororesin in this manner. The short tube 2 is composed of an outer tube 4 made of metal and an inner tube 6 made of fluororesin.

[0004]

In such a conventional lined short tube 2, the ring-shaped collar portion 6a provided at the end of the inner tube 6 made of fluororesin is a cylinder made of fluororesin. -Shaped tube is formed by flare processing, and is bonded to the flange portion 10 of the outer tube 4 with an epoxy adhesive.

However, in the flared portion such as the brim portion 6a of the inner pipe 6, the flared brim portion 6a easily separates from the metallic brim portion 10 and floats up as the usage history increases. Therefore, there is a problem that it is difficult to perform the piping work again. Further, in such a connecting portion, it is possible to seal the joint portion without using a gasket, but since the flange portion 6a is a flat surface seal as a whole, a special pressure is required to maintain the surface pressure. The clamp had to be used for bolting.

On the other hand, when the resin coating is applied instead of the lining, there is a problem that a gasket is inevitably required because the sealing margin cannot be secured, and the resin coating easily causes pinholes. In addition, when used in food production piping lines, 130
Since sterilization may be carried out by applying steam at up to 140 ° C, the resin coating is vulnerable to heat and has a problem that the coating peels off after long-term use. Therefore, the coated piping member is not suitable for such a piping line.

In view of the above situation, the present invention is suitable for a pipe path for a corrosive fluid or a fluid which is not susceptible to contamination, can be tightened with a small tightening force without a gasket, and is also suitable for use at high temperature. It is an object of the present invention to provide a pipe member and a joint structure that are provided.

[0008]

In order to achieve the above object, a lined piping member according to the present invention has a metal collar connected to an inner peripheral surface of a metal tube portion and an end surface of the tube portion. On the surface of each part, when covering the entire surface with a fluororesin, the inner peripheral surface of the tube part is lined with a cylindrical inner layer formed of a fluororesin, and on the surface of the flange part, a fluororesin is formed. A ring-shaped plate body formed from the above is arranged, and a contact portion between the ring-shaped plate body and the cylindrical inner layer is welded and integrated with a fluororesin.

With such a structure, the fluororesin layer can be formed on the surface of the collar portion without the need for flare processing. Further, it is preferable that an annular groove is formed on the surface of the metallic collar portion, and a lining steel pipe member having a concave sealing surface formed on the surface of the collar portion is provided.

Further, it is preferable that an O-ring is previously mounted in an annular groove to form an annular convex portion on the surface of the metallic flange portion, and a convex seal is formed on the surface of the flange portion. A lining steel pipe member having a surface is provided. The above-mentioned lining steel pipes can be arranged by butting the concave sealing surface and the convex sealing surface of the collar portion, and these butting portions can be connected by a simple clamp joint.

With this structure, a desired sealing property can be obtained at the butted portion, and the O-ring can be used as an elastic body, so that the sealing effect can be further improved.

[0012]

BEST MODE FOR CARRYING OUT THE INVENTION An embodiment of the present invention will be described below with reference to the drawings. FIG. 1 shows a lined piping member and a joint structure according to an embodiment of the present invention. In the present specification, the lined piping member is a concept including both the lined steel pipe and the lined joint member. Therefore, the present invention can be applied to a lined steel pipe and also to a lined joint member.

The following examples describe lined joint members. The joint member 20 includes an outer pipe 22 made of metal and an inner pipe 2 made of fluororesin.
4 and. The outer tube 22 is a cylindrical tube portion 2.
2a and a collar portion 28 called a ferrule integrally connected to both ends of the tube portion 22a.
It is composed of a mouthpiece 30 provided with 0.

The inner tube 24 is composed of a cylindrical inner layer 26 made of fluororesin and a ring-shaped plate 32 which is brought into contact with the end face of the brim portion 28 made of metal. Also,
Abutting portion A between the cylindrical inner layer 26 and the ring-shaped plate 32
Are fused and integrated with PFA (polytetrafluoroethylene / perfluoroalkyl vinyl ether copolymer).

As described above, in this embodiment, when the liquid contact portion is covered with the fluororesin, the preliminarily formed cylindrical inner layer 26 is drawn into the outer tube 22, and then,
A ring-shaped plate 32 prepared in advance may be set on the collar portion 28, and the peripheral surface of the contact portion may be fused by PFA. As described above, according to the present embodiment, the ring-shaped plate body 32 and the inner layer 26, which are formed in advance with an appropriate fluororesin,
Since it is welded and integrated by PFA, it is not necessary to flare the ring-shaped plate body. Further, unlike the case where the flare processing is performed, the ring-shaped plate body 32 made of fluororesin does not peel off from the surface of the brim portion 28 made of metal and rise up. Moreover, since the resin layer to be lined is extremely thick as compared with the case of coating, it can withstand use at high temperatures. In addition, defects such as pinholes do not occur. With this, for a long time,
A stable sealing property can be exhibited. The thickness of the lining is 1 mm to 6 mm, preferably 2 to 3
mm.

Further, as shown in FIG. 2, the lining steel pipe having an annular convex portion on the surface of the collar portion is a concave groove 4 on the surface of the collar portion 28 provided on the metal fitting 30 (ferrule).
The O-ring 42 is installed in advance in the 0, and the ring-shaped plate 32
Is applied to the collar portion 28, and the inner layer 26 and the collar portion 32 are PF
It was welded by A. As shown in FIGS. 1 and 2, if the lining steel pipes having the concave and convex sealing surfaces are abutted against each other as shown in FIGS. 1 and 2, the outside of the collar portion 28 is bolted as shown in FIG. With the simple clamp 44 which is not required, a desired tightening force can be obtained only by tightening. Furthermore, since the O-ring 42 functions as an elastic body, the surface pressure of the seal portion can be increased and the sealing performance can be improved.

In the above embodiment, the present invention has been described by taking the straight tubular joint member 20 as an example, but the present invention can of course be applied to other joint members such as a 90 ° elbow and a flexible hose. Moreover, it is also applicable to the end structure of the lining steel pipe.

[0018]

As described above, according to the lined piping member of the present invention, the ring-shaped plate body is formed separately from the inner layer, and the ring-shaped plate body and the inner layer are formed. Since they are integrated by resin welding, the flare portion does not peel off or rise due to the frequency of use as in the past.

Further, according to the present invention, since the flare processing is not performed in this manner, the manufacturing is simple. Further, by using the piping member having the concave sealing surface on the flange portion and the piping member having the convex sealing surface on which the O-ring is mounted as the elastic body as described above, the sealing performance can be improved.

[Brief description of drawings]

FIG. 1 is a half sectional view of a piping member according to an embodiment of the present invention.

FIG. 2 is a sectional view of a piping member according to an embodiment of a convex sealing surface of the present invention.

FIG. 3 is a cross-sectional view of a joint structure in which the piping member shown in FIGS. 1 and 2 is used for a connecting portion.

FIG. 4 is a half cross-sectional view of a conventional piping member.

[Explanation of symbols]

20 Joint member (Piping member) 22 outer tube 22a Sugabe 24 inner tube 26 Inner layer 28 Tsuba 30 mouth metal fittings 32 plates 40 groove 42 O-ring

─────────────────────────────────────────────────── ─── Continuation of front page (51) Int.Cl. ⁷ Identification code FI theme code (reference) B29L 23:00 B29L 23:00 (72) Inventor Koji Takagi 58 Omotesa, Tarui-cho, Fuwa-gun, Gifu Prefecture No. 2 Goto Iron Works Co., Ltd. (72) Inventor Tatsuro Tanabe 58 No. 2 Omotesa, Tarui-cho, Fuwa-gun, Gifu Prefecture F-terms at Go Tekko Works Co., Ltd. (reference) 3H016 CA01 3H024 EC06 ED03 EE01 EF05 EF17 3H111 AA01 BA01 CB08 CB14 CB22 CB28 CC12 DA08 DB10 4F211 AD03 AD12 AD25 AG03 AG08 AG24 AG28 AH11 AH43 SC03 SD04 SH18 TA01 TC08 TC11 TD07 TH06

Claims (4)

[Claims] 1. An inner peripheral surface of a metal pipe part and a surface of a metal collar part connected to an end face of the metal pipe part are coated with a fluororesin on the inner peripheral surface of the pipe part respectively. Lining a tubular inner layer made of fluororesin, and arranging a ring-shaped plate made of fluororesin on the surface of the collar portion. The ring-shaped plate and the tube are formed. The contact part with the inner layer
A lined piping member that is welded and integrated with a fluororesin. 2. The lined piping member according to claim 1, wherein an annular groove is formed on a surface of the metallic collar portion. 3. The lining according to claim 2, wherein an O-ring is preliminarily mounted in an annular concave groove to form an annular convex portion on the surface of the metallic collar portion. Plumbing members. 4. The lining steel pipe member according to claim 2, wherein a concave sealing surface is formed on the surface of the collar portion, and the lining according to claim 3, wherein a convex sealing surface is formed on the surface of the collar portion. A joint structure in which steel pipe members are arranged in abutment with each other and these abutting portions are connected by a simple clamp joint.