JP3056326B2 - Lining pipe flange structure - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a flange structure of a lining pipe in which the inner surface of a metal pipe is coated with a synthetic resin to improve corrosion resistance and chemical resistance, for example, as a pipe material for hot water supply, water supply or air conditioning.

[0002]

2. Description of the Related Art In a lining pipe in which the inner surface of a metal pipe is coated with a synthetic resin such as a thermoplastic resin, a movable flange, a so-called loose flange, is provided on the outer periphery of the pipe in order to connect the pipes at the pipe ends. There are cases.

[0003] Conventionally, the structure of a lining pipe having such a loose flange is shown in FIG.
A loose flange 62 movable in the circumferential direction and the axial direction of the pipe 61 is inserted around the outer circumference of the lining pipe 61 composed of the metal pipe 61a and the resin lining layer 61b on the inner surface thereof. Has a structure in which an annular projection 63 called a stub end is fixed by welding.

Such a structure is usually obtained by welding (stub-end welding) the annular projection 63 to the end of the metal tube 61a and then lining the inner surface of the annular projection 63 and the end surface of the projection 63 with resin.

[0005]

In the above-described conventional flange structure of a lining pipe, since the loose flange 62 moves in the pipe axis direction, both the metal working step or the lining step at the time of manufacturing is performed. In the above, since the loose flange 63 moves in the axial direction along the outer peripheral surface of the pipe at the time of lateral holding and processing, the loose flange 63 is temporarily fixed to prevent this movement,
Or in accordance with the attitude of the tube, for example, there is the lower side of the projection side two loose flange 62 working such troublesomeness that shall be performed after a state of being moved within the ends of the projections 63 .

[0006] Also, when the product is transported or the piping is constructed, the movement of the loose flange in the axial direction is similarly troublesome. Especially when connecting two pipes in a vertical pipe, for example, when connecting the lower end of the upper pipe to the upper end of the lower pipe, the loose flange on the upper side of the upper pipe drops. It will come. In this case, wrap a rope or the like around an appropriate place on the outer peripheral surface of the pipe to prevent the loose flange from dropping, or drop the upper loose flange in advance and lower it in that state. It is necessary to tighten the loose flange on the side against the loose flange of the lower tube,
Tightening work becomes very difficult. By tightening the upper loose flange first, and then tightening the lower loose flange, such problems can be solved.However, in the case of new piping, vertical piping is to be applied from bottom to top. Such a procedure cannot be adopted because it is usual to put pipes.

Further, in the conventional structure, since the projection 63 at the end of the pipe is fixed by welding, lining processing can be performed only after that. Before this lining processing, in particular, welding on the inner surface side of the pipe is performed. The spatter had to be carefully removed and the effort was enormous.

[0008] The present invention has been made in view of such circumstances, the pipes are easy to handle at the time of manufacturing, transportation and pipe construction, and various workability is good. An object of the present invention is to provide a flange structure of a lining pipe that can reduce labor during manufacturing.

[0009]

To achieve the above object, according to an aspect of the flange structure of the lining tube of the invention described in claim 1 of the present patent application, the lining the inner surface of the metal tube with a resin layer
In the lining pipe thus formed, the pipe end is bent to the outer peripheral side, and a loose flange rotatable with respect to the pipe is disposed adjacent to the bent pipe end, and the loose flange is sandwiched therebetween. in the pipe outer peripheral surface of the opposite side of the pipe end bent portion, the movement restricting portion is provided for restricting the movement in the tube axis direction of the loose flange, the movement
The regulating part is caulked and fixed to the outer peripheral surface of the lining pipe.
Vignetting wherein Dzu by a ring.

A liner according to the invention described in claim 2 of the present application.
The flange structure of the metal pipe is such that the inner surface of the metal pipe is
End of the lining pipe
Is bent to the outer peripheral side, and it is
A rotatable loose flange is provided for the pipe.
And the pipe end with the loose flange
On the outer peripheral surface of the pipe opposite to the bent part,
A movement restricting section is provided to restrict movement in the pipe axis direction.
Therefore, the movement restricting portion melts on the outer peripheral surface of the lining pipe.
At least one protruding member or ring-shaped part in contact
It is characterized by being a material.

[0011]

With the movement restricting portion, the loose flange can move only in the axial direction of the pipe between the moving restricting member and the bent portion of the pipe end. The defect is eliminated.

In addition, by eliminating the stub end welding by using the pipe end as a bent portion, adhesion of welding spatter particularly to the inner surface of the pipe is eliminated, and the removal work at that portion can be omitted.

[0013]

FIG. 1 is a sectional view showing the structure of an embodiment of the present invention. A bent portion 11 bent toward the outer peripheral side is formed at the pipe end of the lining pipe 10 in which the resin lining layer 10b is formed on the inner surface of the metal pipe 10a.

Adjacent to the bent portion 11, the outer peripheral surface of the lining tube 10 has an inner diameter larger than the outer diameter of the tube 10 and a plurality of bolt holes 12a.
A loose flange 12 having a hole 12a formed therein is inserted therein.
A loose flange 12 is provided on the outer peripheral surface of the pipe 10 on the side opposite to the side 1.
Ring 1 with outer diameter larger than inner diameter
3 are provided.

The dimension between the caulking ring 13 and the bent portion 11 is slightly longer than the thickness dimension of the loose flange 12, so that the loose flange 12 is rotatable on the outer peripheral surface of the lining tube 10 and slightly. It can move only by distance.

The outer diameters of the bent portion 11 and the caulking ring 13 are smaller than the diameter of the circumference connecting the innermost bolt holes 12a of the loose flange 12.

According to the embodiment of the present invention described above, although the loose flange 12 is rotatable with respect to the lining tube 10, the axial movement of the lining tube 10 is prevented by the caulking ring 13.

Further, according to this structure, since there is no welding portion, no operation for removing welding spatter is required at the time of manufacturing. The caulking ring 13 and the bent portion 1
The dimension between the two is not particularly limited as long as the loose flange 12 can be easily rotated and the backlash in the axial direction can be prevented, and is not particularly limited, but is preferably larger than the thickness dimension of the loose flange 12. It is preferable to set the size larger by about 0.5 mm to 10 mm.

Such an embodiment of the present invention can be manufactured by the following procedure. FIG. 2 is a procedure explanatory view showing an example of the manufacturing method.

First, as shown in FIG. 1A, a ring 13a and a loose flange 12 are inserted into the outer periphery of a metal tube 10a, and the tube end of the metal tube 10a is bent by punching or the like to form a bent portion 11.

Next, (B), the in a state of being adjacent to the bent portion 11 a loose flange 12, for example 2
The split molds 21a and 21b and the hydraulic cylinder 22a,
The ring 13a is pressed from its outer periphery using 22b or the like.
The diameter is reduced to form a swage ring 13.

Thereafter, a softened resin is attached to the inner surface of the metal tube 10a and the end surface of the bent portion 11 or
Alternatively, by forming the resin lining layer 10b by performing powder coating or the like, the structure shown in FIG. 1 is obtained.

In the above manufacturing method, the ring 1
Instead of the step of caulking 3a, as shown in FIG. 3, the pipe end of the metal pipe 10a is previously reduced in diameter over the insertion range of the loose flange 12 and the caulking ring 13, and then the reduced diameter section is removed. The structure shown in FIG. 1 is similarly obtained by expanding the diameter by bulging or the like and forming the bent portion 11.

The structure of the embodiment of the present invention shown in FIG. 1 is not the stage of the metal tube 10a but the resin lining layer 1
Ob can also be obtained by processing in a state where the lining tube 10 is formed by forming Ob. That is, after inserting the ring 13a and the loose flange 12 into the outer periphery of the lining tube 10 in the same manner as in the above example, the tube end is bent toward the outer periphery by punching or the like to form a bent portion 11,
In the same manner as in the above example, the diameter of the ring 13a is reduced to form the caulking ring 13. Also in this manufacturing method, the procedure shown in FIG. 3 can be applied. The diameter of the pipe end of the lining pipe 10 is reduced in advance, and after the loose flange 12 and the caulking ring 13 are inserted, expansion is performed by bulging or the like. It may be diameter.

As described above, if the method of forming the flange portion by post-processing the lining tube 10 is adopted, the bent portion 11 does not need to be turned back by hand or the like at the time of resin lining. Here, in this method, the resin lining layer 10b or its adhesive layer needs to be stretched in the forming step of the bent portion 11, but according to the result of an experiment using a pipe in which graft polyethylene is lined on the inner surface of a 100A steel pipe. The desired structure shown in FIG. 1 could be easily obtained.

FIG. 4 is a sectional view showing the structure of another embodiment of the present invention. The difference between this example and the example of FIG. 1 is that the member for restricting the movement of the loose flange 12 in the tube axis direction is replaced by a caulking ring 13 of FIG. 1 and a projection member 43 fixed by welding. It is.

That is, the lining tube 10, the bent portion 11 and the loose flange 12 have the same structure as that of FIG. 1, but the outer circumferential surface of the lining tube 10 opposite to the bent portion 11 with the loose flange 12 interposed therebetween has a loose shape. One or a plurality of protrusion members 43 for restricting the movement of the flange 12 in the axial direction are welded. This projection member 43
The dimension between the bent portion 11 and the bent portion 11 may be such that the loose flange 12 can be easily rotated and the backlash in the axial direction can be prevented. Is also preferably increased by about 0.5 mm to 10 mm.

The shape of the projection member 42 is the same as that of the loose flange 1.
Any ring 2 can be used as long as it is rotatable on the outer peripheral surface of the tube 10 and restricts movement in the axial direction, and a ring-shaped member can also be used. However, this projection member 4
The tip diameter in the welding state of the running pipe 3 to 3 is:
Like the caulking ring 13 in the previous example, the bolt hole 1 is larger than the inner diameter of the loose flange 12.
It is necessary to make the diameter smaller than the diameter of the circumference connecting the innermost side of 2a.

Also in this example, the loose flange 12 is rotatable with respect to the lining pipe 10 as in the example of FIG.
Is prevented from moving in the axial direction, and problems during various operations are eliminated.

Further, according to this structure, the stub end welding is not required as in the prior art, so that the finish welding step of the corner R portion of the stub end is unnecessary, and no welding spatter adheres to the inner surface of the pipe. The operation of removing the spatter at that portion can be omitted.

FIG. 5 is an explanatory view of a procedure showing an example of the manufacturing method of the embodiment shown in FIG. First, as shown in (A), one or a plurality of projection members 43 are spot-welded, spot-welded, or continuously welded to a predetermined position on the outer peripheral surface of the metal tube 10a.

Thereafter, as shown in FIG.
Resin lining on the inner surface of the
To form a lining tube 10. Next, after inserting the loose flange 12 from the tube end side, the tube end portion is bent to the outer peripheral side by punch molding or the like, and the bent portion 11 is formed to obtain the structure shown in FIG.

It should be noted that, instead of this manufacturing method, the metal tube 10
In the state a, the bent portion 11 is formed by welding the projection member 43, inserting the loose flange 12, and punching the pipe end.
Then, the resin having the structure shown in FIG. 4 is obtained by performing resin lining on the inner surface of the metal tube 10a including a flange turning process on the end surface portion of the bent portion 11 after that. . However, adopting the manufacturing method shown in FIG. 5 desirably eliminates the need for a flange turning process in the resin lining step.

Further, by employing spot welding for welding the projection member 43, the work of removing spatter on the outer peripheral surface can be reduced because the scattering of spatter can be reduced.

In each of the above embodiments, the material of the metal tube 10a can be any metal such as iron-based, copper-based, or aluminum-based, including steel, which has extensibility. However, in the structure shown in FIG. In addition, any resin that can be welded may be used. The resin used for the resin lining layer 10b may be a thermoplastic resin such as vinyl chloride, polyethylene, graft polyethylene, or polyamide, or a thermosetting resin such as phenol or epoxy. Resin can be employed. The metal tube and the resin layer may be bonded via an adhesive, hot melt, or the like, or may have a structure in which the resin itself is directly bonded to the metal tube. However, for non-adhesive resin such as polyvinylidene fluoride, it is not necessary to adhere to the metal pipe at all, but the lining is affected by the heat when welding is performed from the outer surface of the pipe. In such a case, it is desirable to adopt a structure having no welded portion as in the structure shown in FIG.

The material of the caulking ring 13 or the protruding member 43 in the present invention is selected in consideration of corrosion and the like.
A metal material of the same quality as that of the metal tube 10a is preferable, but basically, a material having strength enough to withstand the moving impact of the loose flange 12 is sufficient.

[0037]

As described above, according to the present invention,
A bent portion is formed at the pipe end of the lining pipe, a loose flange rotatable with respect to the pipe is disposed adjacent to the pipe end bent section, and the pipe end bent section is sandwiched between the loose flange. On the opposite side of the outer peripheral surface of the pipe, a movement restricting part is provided to restrict the movement of the loose flange in the pipe axis direction. Inconveniences such as movement to the surface are eliminated, handling is facilitated, and various workability is improved. In addition, since stub end welding at the pipe end is not required, the work of removing welding spatter on the inner surface of the pipe and the welding finish of the R portion at the stub end and the pipe end are not required, and the structure thereof is made of resin. After lining, the flange structure can be machined, eliminating the need for special lining equipment such as flange turning during lining, which can significantly reduce manufacturing man-hours. it can.

[Brief description of the drawings]

FIG. 1 is a sectional view showing the structure of an embodiment of the present invention.

FIG. 2 is a procedure explanatory view showing an example of the manufacturing method.

FIG. 3 is an explanatory diagram of main steps of another manufacturing method for obtaining the structure of FIG. 1;

FIG. 4 is a sectional view showing the structure of another embodiment of the present invention.

FIG. 5 is an explanatory view of a procedure showing an example of the manufacturing method.

FIG. 6 is a cross-sectional view showing the structure of a conventional lining pipe having a loose flange.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 10 Lining tube 10a Metal tube 10b Resin lining layer 11 Bent part 12 Loose flange 13 Caulking ring 43 Projection member

Claims (2)

(57) [Claims] 1. A lining pipe in which an inner surface of a metal pipe is lined with a resin layer, a pipe end is bent to an outer peripheral side, and a loose end rotatable with respect to the pipe adjacent to the bent pipe end. A flange is provided, and a movement restricting portion for restricting the movement of the loose flange in the tube axis direction is provided on the outer peripheral surface of the tube opposite to the tube end bent portion with the loose flange interposed therebetween. The above
The movement restricting part is fixed by caulking to the outer peripheral surface of the lining pipe.
The flange structure of the lining pipe, characterized in that it is a bent ring . 2. The inner surface of a metal tube is lined with a resin layer.
In the lining pipe, the pipe end is
Bends into the tube adjacent to this tube end bend.
If a rotatable loose flange is provided
In addition, the tube end bent section with this loose flange
On the outer circumferential surface of the pipe opposite to the
There is a movement restriction section that regulates the movement of
The movement restricting part is a small part welded to the outer peripheral surface of the lining pipe.
At least one protruding member or ring-shaped member
And a flange structure of the lining pipe.