JPH06147388A - Fusing/connecting method for pipe coupling - Google Patents

Abstract

PURPOSE:To provide the fusing/connecting method of a pipe coupling generating no step in a pipe and not impairing the outer appearance by molding and processing the generated beads in space sections, not preventing the generation of the beads. CONSTITUTION:The inner periphery 11 of a pipe coupling 1 and the outer periphery 21 of a pipe 2 to be inserted into the inner periphery 11 are heated, then the pipe 2 is inserted into the pipe coupling 1 to socket-fuse and connect the inner periphery 11 of the pipe coupling 1 and the outer periphery 21 of the pipe 2, and space sections 10, 20 are recessed on the pipe coupling 1 where beads 4 are generated in the fused and connected state or at the portion of the pipe 2 where beams 4 are generated before the fusion/connection in advance so that beads are generated in the space sections 10, 20 at the time of fusion/ connection.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a fusion splicing method by socket connection between a pipe joint and a pipe.

[0002]

2. Description of the Related Art Generally, after heating an inner peripheral surface of a pipe joint and an outer peripheral surface of a pipe to be inserted into the inner peripheral surface, the pipe is inserted into the pipe joint to form an inner peripheral surface of the pipe joint and a pipe. A method of fusion-bonding the outer peripheral surface of the socket with the socket is known. In addition, when fusion-bonding is performed in this manner, protrusions of molten resin called beads are generated at the ends of the pipe joint and the pipe.

Therefore, conventionally, as a method of treating a bead generated during such fusion bonding, for example, a method disclosed in JP-A-57-146989 is known. That is, the inner surface of the receiving opening of the pipe joint is alternately made to be uneven in the longitudinal direction, and the inner surface of the receiving opening is softened by heating to prevent the generation of a ring-shaped bead in the joint portion.

[0004]

However, in the case of the above-mentioned conventional fusion bonding method, although the protrusion amount of the molten resin is reduced by being absorbed in the uneven portion, the generation of beads cannot be completely eliminated, Beads will be generated to some extent. Therefore, as shown in FIG. 9, when a pipe b is formed by connecting the pipe b to the other end of the pipe joint a fusion-bonded in this way, a step is generated at the bead c portion, and dust or dirt is generated. This causes an inconvenience that scales are easily attached. Further, beads c are also generated on the outer surface of the fusion-bonded tube b, which is not preferable in terms of the appearance of the product.

The present invention has been made in view of the above situation, and does not prevent the generation of beads, but forms the generated beads in the space portion, so that there is no step in the pipe line. Moreover, it is an object of the present invention to provide a fusion bonding method for pipe joints that does not impair the appearance.

[0006]

A fusion bonding method for a pipe joint according to the present invention for solving the above-mentioned problems includes an inner peripheral surface of the pipe joint and an outer peripheral surface of a pipe inserted into the inner peripheral surface. After heating, a pipe is inserted into this pipe joint to perform socket fusion bonding of the inner peripheral surface of the pipe joint and the outer peripheral surface of the pipe, and a bead will be generated in the fusion bonded state. And / or in the bead-generating portion of the pipe, a space is formed in advance before fusion bonding, and / or a space is formed by providing a jig. Is caused by.

[0007]

According to the present invention, a space is provided in advance in a bead-generating portion of a pipe joint and / or a pipe where a bead is generated in a fusion-bonded state before the fusion-bonding, and / or a jig. By forming the space portion by providing the above, the bead generated at the time of fusion bonding is solidified in this space portion.

[0008]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of the present invention will be described below with reference to the drawings.

[0009]

[Embodiment 1] FIG. 1 shows each working step of a fusion bonding method for a pipe joint 1.

That is, this fusion bonding method is applied to the pipe joint 1
The inner peripheral surface 11 of the pipe joint 1 and the outer peripheral surface 21 of the pipe 2 inserted into the inner peripheral surface 11 are heated by the heater 3, and then the pipe 2 is inserted into the pipe joint 1 to form the inner peripheral surface 11 of the pipe joint 1. And outer surface 2 of tube 2
1 is a method for fusion-bonding sockets 1 and 1, in which a bead 4 is generated in the fusion-bonded state, at the end of the pipe joint 1 and / or the pipe 2, a space portion 10 before fusion-bonding,
20 is recessed, and the bead 4 at the time of fusion bonding is generated in the space portions 10 and 20.

The end portion of the pipe joint 1 is cut into a taper shape so that the diameter decreases from the outer peripheral surface 12 side to the inner peripheral surface 11 side, and the cut portion is formed as a space portion 10. . The space portion 10 has a volume sufficient to accommodate the bead 4 generated between the end portion of the pipe joint 1 and the outer peripheral surface 21 of the pipe 2 during fusion bonding. The volume of the space 10 is determined by the dimensions of the pipe joint 1 and the pipe 2, the heating temperature of the heater 3, the heating time, and the like.

The end of the tube 2 is cut into a tapered shape from the outer peripheral surface 21 side to the inner peripheral surface 22 side, and the cut portion is formed as a space 20. This space 2
The volume of 0 is set so that the bead 4 generated between the end portion of the pipe 2 and the inner peripheral surface 11 of the pipe joint 1 during fusion bonding can be sufficiently accommodated. The volume of this space 20 is similar to that of the space 10 of the pipe joint 1, and the dimensions of the pipe joint 1 and the pipe 2,
It is determined by the heating temperature of the heater 3 and the heating time.

The shape of the space portion 20 of the pipe 2 is not particularly limited as long as the bead 4 generated between the end portion of the pipe 2 and the inner peripheral surface 11 of the pipe joint 1 can be effectively stored. The space portion 20 is not limited, and may be, for example, the space portion 20 having various shapes as shown in FIG.

The shape of the space portion 10 of the pipe joint 1 is also particularly limited as long as the bead 4 generated between the end portion of the pipe joint 1 and the outer peripheral surface 21 of the pipe 2 can be accommodated effectively. However, the space 10 may have various shapes as shown in FIG. 3, for example. Further, as shown in FIGS. 1A and 1B, the bead 4 generated on the inner peripheral surface 11 of the pipe joint 1
A bead 4 generated on the inner peripheral surface 11 of the pipe joint 1 within the groove 13 is provided with a groove 13 of various shapes.
May be stored. In the case of this pipe joint 1, the pipe 2 used for fusion bonding may be the pipe 2 having the space portion 20 or may be the normal pipe 2 having no space portion 20.

[0015]

Second Embodiment This example is shown in FIGS.

That is, in this example, the pipe joint 1 is provided with the jig 5 in advance before fusion bonding, so that the space 50 is formed.
Since the other configurations are the same as those in the first embodiment, only the differences will be described here, and the other description will be omitted. The same members as those in the first embodiment are designated by the same reference numerals.

The jig 5 is provided on the inner peripheral surface 11 and the outer peripheral surface 12 of the pipe joint 1.

Of these, the jig 5 provided on the inner peripheral surface 11
Is formed in a cylindrical shape having a flange portion 51 on the outer side thereof, and when the flange portion 5 is inserted into the inner peripheral surface 11 of the pipe joint 1,
1 is engaged with the other end of the pipe joint 1 and inserted into a predetermined position. Further, a stepped portion 52 is provided on the outer peripheral surface of the tip of the jig 5.
And the inner peripheral surface 11 of the pipe joint 1 is formed.
A space 50 for accommodating the bead 4 is formed between and. At this time, the shape of the space 50 formed is not particularly limited, but as shown in FIG. 5, when the pipe 2 is connected to the other end of the pipe joint 1 to form a pipe line. In addition, it must be possible to construct a uniform pipe line that does not cause a step. Also, as shown in FIG.
The volume of the space 50 may be made smaller than the amount of the bead 4 generated so that the excess bead 4 is allowed to escape in a predetermined direction. In this case, the bead 4 can be easily processed by cutting off the thin portion of the bead 4 that has escaped after fusion bonding.

On the other hand, the jig 5 provided on the outer peripheral surface 12 is
It is formed in a cylindrical shape having a collar portion 53 in its inward direction, and when the outer peripheral surface 12 of the pipe joint 1 is covered, this collar portion 5
A space 50 for accommodating the bead 4 is formed between the pipe 3 and the end of the pipe joint 1. Then, at the time of fusion bonding, by molding the bead 4 into an appropriate shape in the space portion 50, fusion bonding excellent in appearance can be performed. At this time, the shape of the bead 4 is not particularly limited, and the bead 4 can be formed into various shapes as shown in FIG. 7, for example.

Although the present embodiment describes the case where the jig 5 is provided on the pipe joint 1, the jig 5 is provided on the pipe 2 by exchanging it with a desired jig 5 to perform fusion bonding. Alternatively, the jigs 5 may be provided on both sides to perform fusion bonding.

Further, although the present embodiment describes the case where the jig 5 is inserted into the ordinary pipe joint 1 and the pipe 2 and fusion-bonded, the space portions 10 and 20 as shown in the first embodiment. The fusion bonding may be performed using the pipe joint 1 and the pipe 2 having the. In this case, as shown in FIG. 8, at the stage where the resin material is still in a molten state after fusion bonding, the beads 4 generated in the spaces 10 and 20 are pressed by the jig 5 to be molded into a desired shape. You may Further, by inserting the jig 5 in advance before fusion bonding, it is possible to easily determine the insertion allowance of the tube 2 during fusion bonding.

As the jig 5, it is preferable to use a jig whose contact surface with the bead 4 is plated with chrome or the like to improve the peelability.

[0023]

As described above, according to the present invention, the bead generated at the time of fusion bonding can be solidified in the space portion, so that there is no step in the pipe after connection and the external appearance. Also, excellent and substantially beadless fusion bonding can be performed.

[Brief description of drawings]

FIG. 1 is a process drawing showing an outline of a fusion bonding method for pipe joints.

FIG. 2 is a partial cross-sectional view showing various shapes of a space formed in a tube.

FIG. 3 is a partial sectional view showing various shapes of a space formed in the pipe joint.

FIG. 4 is a process diagram showing an outline of a fusion bonding method for pipe fittings according to a second embodiment.

FIG. 5 is a cross-sectional view showing an example of a bead on the inner surface side of a pipe joint formed by a jig.

FIG. 6 is a process diagram showing an example of a bead treatment on the inner surface side of a pipe joint by a jig.

FIG. 7 is a partial cutaway view showing various shapes of a bead on the outer surface side of a pipe formed by a jig.

FIG. 8 is a process drawing showing another embodiment of the fusion bonding method.

FIG. 9 is a partial cutaway view showing a state of socket fusion welding of a conventional pipe joint and a pipe.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Pipe joint 10 Space part 11 Inner peripheral surface 2 Pipe 20 Space part 21 Outer peripheral surface 4 Bead 5 Jig 50 Space part

Claims (1)

[Claims] 1. An inner peripheral surface of a pipe joint and an outer peripheral surface of the pipe joint are heated by heating an inner peripheral surface of the pipe joint and an outer peripheral surface of the pipe inserted into the inner peripheral surface. A method of fusion-bonding a surface with a socket, in which a bead is generated in the fusion-bonded state, and a space is previously provided in the bead-generating portion of the pipe joint and / or the pipe before fusion-bonding. And / or a jig is provided to form a space portion, and a bead at the time of fusion bonding is generated in the space portion.