JP3895705B2 - Terminal fixing part of metal reinforced plastic pipe - Google Patents

Description

[0001]
BACKGROUND OF THE INVENTION
The present invention relates to a terminal fixing portion of a plastic pipe reinforced with a metal strip, and more specifically to an improvement of a terminal fixing portion of a metal strip in a connection terminal of a metal reinforced plastic pipe.
[0002]
[Prior art]
Conventionally, for example, a cloth tape or a metal strip made of steel or the like is spirally reinforced on a plastic tube having an outer diameter of 200 mm or more, and further, for example, a cloth tape is wound thereon. Metal-reinforced plastic pipes such as water supply pipes and gas supply pipes covered with a plastic protective sheath are known.
[0003]
When connecting this kind of metal reinforced plastic pipes, as shown in FIG. 7, the protective sheath described above is used to expose the plastic pipe 1 by the length necessary for the connection at the end of the metal reinforced plastic pipe to be connected. And strips of metal strips, etc., are stripped to the required length, and pipe joints are mounted so as to straddle the exposed plastic pipes 1.
[0004]
In FIG. 7, reference numeral 3 denotes a stiffener made of hard resin such as steel or polyacetal, which is inserted inside the plastic pipe 1 as necessary so that the shape of the plastic pipe 1 does not collapse when the pipe joint is mounted, and reference numeral 4 denotes the pipe. A protective ring inserted first into the gap between the joint body 2 and the plastic tube 1 is shown.
Reference numeral 5 denotes a rubber packing, and the protective ring 4 is mounted to prevent cold flow of the rubber packing, and the material thereof is made of fiber reinforced rubber or the like.
[0005]
Reference numeral 6 denotes a push wheel. The push ring 6 and the pipe joint main body 2 are connected to each other by a bolt 9 and a nut 19 that is screwed to the retainer 7 that presses the packing 5.
Here, the retainer 7 is formed of a hard resin such as a steel material or polyacetal, as in the case of the stiffener 3.
[0006]
Reference numeral 8 denotes a lock ring inserted between the press ring 6 and the plastic tube 1, and this lock ring 8 has an opening in its circumferential direction, and teeth are engraved on its inner surface. When the bolt 9 and the nut 19 are tightened, the diameter is reduced by being pressed by the rear end of the retainer 7 and the tapered surface of the inner surface of the push ring 6. As a result, the teeth bite into the outer surface of the plastic pipe 1 to prevent the plastic pipe 1 from coming out of the pipe joint in the axial direction. Incidentally, the material of the lock ring 8 is also made of a hard resin such as steel or polyacetal.
[0007]
Here, the pipe joint includes at least the protection ring 4, the rubber packing 5, the push ring 6, the retainer 7, the lock ring 8, the bolt 9, and the nut 19 in addition to the pipe joint body 2.
[0008]
In FIG. 7, the left side of the pipe joint is omitted for easy understanding of the drawing. The reason is that the plastic tube 1 on the left side is connected in the same manner as that on the right side. Moreover, in FIG. 7, the upper part of the center line of the plastic pipe 1 shows the longitudinal cross-sectional view, and the lower part has shown the top view.
[0009]
At the other end of the push ring 6, a metal strip fixing ring 20 that presses and fixes the metal strip 10 spirally wound on the surface of the plastic tube 1 onto the plastic tube 1 is mounted. The metal strip fixing ring 20 is divided into two so that the end of the spirally wound metal strip 10 can be sandwiched between the plastic tube 1 and fixed. Then, the bolt 21 is passed through the bolt fastening through holes provided in the flanges 22 at both ends, and the bolt 21 is fastened with a nut so that it is mounted on the plastic tube 1 and the end of the metal strip 10 is fixed. Thereafter, the metal strip fixing ring 20 is connected to the end of the pusher wheel 6 with a bolt or the like.
[0010]
On the other hand, as another method of fixing the metal strip 10 to the end portion of the pipe joint, a method of directly welding and fixing the end portion of the metal strip 10 to the end portion of the push ring 6 of the pipe joint is also known.
There is also a method in which a steel wire or a copper wire is wound around the end portion of the metal strip 10 in the vicinity of the end portion of the press wheel 6 and fixed.
[0011]
[Problems to be solved by the invention]
By the way, in the case of the method shown in FIG. 7, when this metal reinforced plastic pipe is a water supply pipe, the pipe joint of this metal reinforced plastic pipe in the sea or water repeatedly vibrates over a long period due to waves or the like. receive. As a result, the fixing of the metal strip fixing ring 20 is loosened, the inner metal strip 10 slips loose due to its rigidity, and the protective effect of the plastic pipe 1 in the vicinity of the pipe joint end by the metal strip 10 cannot be expected. There was a problem.
[0012]
Moreover, in the case of the method of welding the edge part of the metal strip 10 to the push ring 6 of a pipe joint, for the convenience of work, after welding the plastic pipes 1 with a pipe joint, this welding work must be performed. Therefore, the surface of the plastic pipe 1 exists immediately next to the metal strip 10 during welding. As a result, when the end of the metal strip 10 is welded to the end of the presser wheel 6, the tip of the welding rod touches the surface of the plastic tube 1 or the surface of the plastic tube 1 is melted by the heat generated during welding. There was a problem of attaching.
[0013]
Furthermore, in the case of the method of winding and fixing the end of the metal strip 10 with a steel wire, a copper wire or the like, there is a problem that the steel wire or the copper wire stretches and loosens with time, and the rigid metal strip 10 slips out. there were.
[0014]
In view of the above problems, the object of the present invention is to provide a metal strip that is loosened with the metal strip fixing ring over time even when a metal-reinforced plastic tube having a pipe joint is used in the sea or water for a long time. It is an object of the present invention to provide a terminal fixing portion of a metal reinforced plastic tube that does not damage the surface of the inner plastic tube when the metal ring is fixed or the metal strip is fixed.
[0015]
[Means for Solving the Problems]
In order to achieve the above object, the present invention provides a pipe joint attached to a portion of the end of a metal reinforced plastic pipe formed by spirally winding a metal strip around the plastic pipe, where the plastic pipe is exposed. The metal strip fixing ring is fixed to the end portion of the metal reinforced plastic pipe, and the metal strip fixing ring is connected to the end of the pipe joint. Has a flange that has an opening in the circumferential direction or is divided into two parts and has a through-hole for bolt tightening in the opening or the divided part. While holding the mounted metal strip fixing block with the flange, a bolt tightening through hole provided in the metal strip fixing block and a bolt tightening through hole provided in the flange To match the by allowed through the bolt, it is characterized in that the terminal of the metal strip fixed by metal strip fixing ring by which to secure a nut.
[0016]
According to the terminal fixing portion of the metal-reinforced plastic pipe of the present invention thus configured, the metal strip fixing ring has an opening in the circumferential direction or is divided into two, and the opening or two A bolt provided in the metal strip fixing block, having a flange having a through-hole for bolt tightening in the split portion, and holding the metal strip fixing block attached to the end portion of the metal strip with the flange The end of the metal strip is fixed with the metal strip fixing ring by aligning the through hole for tightening with the through hole for tightening the bolt provided in the flange and penetrating the bolt, and fixing it with a nut. It has become.
[0017]
That is, the metal strip fixing block provided at the end of the metal strip is sandwiched in a pressed state by the metal strip fixing ring and fixed by bolting, so that the metal reinforced plastic pipe having this pipe joint is underwater. Even if you are in water or continue to receive vibrations from waves, the metal strip will not easily slip out of the metal strip fixing ring. Therefore, the metal strip can be securely fixed to the end of the pipe joint over a long period of time, and thus the plastic pipe can be reliably protected by this metal strip for a long period of time.
Even if the metal strip fixing block is connected to the end of the metal strip by welding, the welding operation can be performed at a location away from the surface of the plastic pipe if the metal strip is rewound slightly. There is no risk of damaging the surface of the plastic tube.
[0018]
DETAILED DESCRIPTION OF THE INVENTION
1 to 6 show an embodiment of a terminal fixing portion of a metal-reinforced plastic pipe according to the present invention. FIG. 1 shows a longitudinal sectional view of a portion above the center line of the terminal fixing portion of the metal-reinforced plastic pipe, and the lower portion is omitted because it is symmetrical with the upper portion.
In FIG. 1, the same parts as those shown in FIG. 7 described above are denoted by the same reference numerals, the detailed description will be simplified, and the features of the present invention will be mainly described in detail.
[0019]
In FIG. 1, the stapler 3, the protective ring 4, the rubber packing 5, the pusher wheel 6, the retainer 7, the lock ring 8, and the bolt 9 and the nut 19 that connect the pusher wheel 6 to the pipe joint body 2 are basically shown in FIG. 7. It is the same as the conventional one shown.
The feature of the terminal fixing portion of the metal reinforced plastic pipe of the present invention shown in FIG. 1 is that a metal strip fixing block 30 is attached to the end of the metal strip 10 as indicated by a two-dot chain line in FIG. The metal strip fixing block 30 is sandwiched between the flanges 22 and 22 of the metal strip fixing ring 20, and a bolt 21 inserted in a bolt hole provided in the flange 22 and a nut 23 (FIG. 1). (Not shown in the figure) and is fixed. Incidentally, it is preferable that the metal strip fixing block 30 is made of a steel material or the like and is formed of a hard and tough material.
[0020]
The state in which the metal strip fixing block 30 and the metal strip fixing block 30 are fixed to the metal strip fixing ring 20 will be described in detail with reference to FIGS.
As shown in FIG. 2, a metal strip fixing block 30 is attached to the end portion of the metal strip 10 spirally wound on the plastic tube 1.
As a mounting method, as shown in FIG. 3, the end of the metal strip 10 may be connected to the lower surface of the metal strip fixing block 30 by welding or an adhesive, or the height of the metal strip fixing block 30 as shown in FIG. A notch 32 may be provided horizontally in the vertical direction, and the end of the metal strip 10 may be inserted into the notch 32, and welding or caulking may be connected in this state. In any case, the connection work such as the welding work may be performed in a state where the metal strip 10 is slightly unwound and a distance from the plastic pipe 1 is kept.
Further, in the thickness direction of the metal strip fixing block 30, a bolt fastening through hole 31 used when fixing the metal strip fixing block 30 to the metal strip fixing ring 20 is formed.
[0021]
When the metal strip fixing block 30 is mounted on the end portion of the metal strip 10 as described above, the flange 22 of the metal strip fixing ring 20 having the metal strip fixing block 30 mounted on the end of the push ring 6 as shown in FIG. , 22. At this time, as shown in FIG. 6, the bolt fastening through hole 23 provided in the flange 22 of the metal strip fixing ring 20 and the bolt fastening through hole 31 provided in the metal strip fixing block 30 are made to coincide with each other. Then, bolts 21 are passed through these holes, and are tightened with nuts 24 and fixed in a clamped state.
FIG. 6 shows a cross section of the cross section taken along the line AA in FIG.
[0022]
When the metal strip fixing block 30 is fixed to the metal strip fixing ring 20, the metal strip fixing ring 20 is fixed to the push ring 6. In FIG. 5, reference numeral 40 denotes a bolt insertion hole used at that time, and the metal strip fixing ring 20 is screwed to the press ring 6 through the bolt insertion hole 40. By fixing the metal strip fixing ring 20 to the push ring 6 in this way, the metal strip fixing ring 20 is prevented from rotating around the central axis of the plastic tube 1 on the plastic tube 1 to loosen the metal strip 10.
[0023]
In FIG. 5, as the metal strip fixing ring 20, a split type as shown in FIG. 6 is used. Therefore, the flange 22 exists on both sides of the metal strip fixing ring 20.
However, as this metal strip fixing ring 20, for example, an opening is provided in the circumferential direction of the metal strip fixing ring 20, and a flange 22 is provided at that portion, that is, only the flange 22 that is visible in FIG. It may be a type in which the flange 22 does not exist.
[0024]
According to the above-described end fixing portion of the metal reinforced plastic pipe of the present invention, the metal strip fixing block 30 is connected to the end portion of the metal strip 10 and is sandwiched by the flange 22 of the metal strip fixing ring 20. The bolt-tightening through-hole 23 provided in the bolt and the bolt-tightening through-hole 31 provided in the metal strip fixing block 30 are made to coincide with each other, and the bolt 21 is passed through these holes, which are tightened with the nuts 24, and held. Therefore, the end of the metal strip 10 can be securely fixed. Moreover, since the metal strip fixing ring 20 is connected to the press ring 6, even if the rigidity of the metal strip 10 acts, the metal strip fixing ring 20 does not rotate around the central axis of the plastic tube 1.
Therefore, even if the pipe joint portion of the metal reinforced plastic pipe is used for a long time in the sea or underwater and is repeatedly subjected to vibration by waves or the like, the metal strip 10 fixed by the metal strip fixing ring 20 is used. Is less likely to come loose from the metal strip fixing ring 20. Therefore, the end portion of the plastic tube 1 can be reliably reinforced with the metal strip 10 for a long period of time.
[0025]
Further, according to the present invention described above, even if the metal strip fixing block 30 is temporarily connected to the terminal portion of the metal strip 10 by welding, the welding operation can be performed at a place away from the surface of the plastic pipe 1, so that welding is performed. There is no risk of damaging the surface of the plastic tube 1 during operation.
[0026]
Also, unlike the case where the end of the metal strip 10 is fixed by winding a steel wire or the like, the metal strip fixing ring 20 and the metal strip fixing block 30 are aligned with each other through a bolt-tightening through hole, and the bolt is passed through the bolt. Since it fixes by fastening, the terminal part of the metal strip 10 can be reliably fixed to the metal strip fixing ring 20 over a long period of time. Therefore, reinforcement by the metal strip 10 in the vicinity of the end portion of the plastic pipe 1, that is, in the vicinity of both sides of the installed pipe joint, can be ensured for a long time.
[0027]
【The invention's effect】
As described above, according to the terminal fixing portion of the metal reinforced plastic pipe of the present invention, the metal reinforced plastic pipe having a pipe joint is fixed by the metal strip fixing ring even when used for a long time in the sea or in water. The possibility that the metal strip that has been loosened over time will come out of the metal strip fixing ring becomes extremely small.
Therefore, the plastic pipe can be reinforced with metal strips at both ends of the pipe joint for a long period of time.
In addition, it is also possible to provide a terminal fixing portion of a metal-reinforced plastic pipe that does not damage the surface of the plastic pipe when the metal strip is fixed.
[Brief description of the drawings]
FIG. 1 is a half sectional view showing an embodiment of the present invention.
FIG. 2 is a perspective view showing a state in which a metal strip fixing block is attached to the end portion of the metal strip according to one embodiment of the present invention.
FIG. 3 is a longitudinal sectional view showing a method of connecting a metal strip end to a metal strip fixing block according to an embodiment of the present invention.
FIG. 4 is a longitudinal sectional view showing another method of connecting a metal strip end to a metal strip fixing block according to an embodiment of the present invention.
FIG. 5 is a perspective view showing a state in which a metal strip fixing block is fixed to a metal strip fixing ring according to an embodiment of the present invention.
6 relates to one embodiment of the present invention and is a cross-sectional view taken along the line AA of FIG.
FIG. 7 is a half sectional view showing a terminal fixing portion of a conventional metal reinforced plastic pipe.
[Explanation of symbols]
DESCRIPTION OF SYMBOLS 1 Plastic pipe 2 Pipe joint body 6 Press ring 10 Metal strip 20 Metal strip fixing ring 21 Bolt 22 Flange 23 Bolt tightening through hole 30 Metal strip fixing block 31 Bolt tightening through hole

Claims (1)

A metal strip fixing ring in which a pipe joint is attached to the exposed portion of the end of the metal reinforced plastic pipe in which a metal strip is spirally wound around the outside of the plastic pipe, and is attached to the end of the pipe joint The metal strip fixing ring is connected to the end of the pipe joint, and the metal strip fixing ring is connected to the end of the pipe joint. The metal strip fixing ring has an opening in its circumferential direction. Or a flange having a through-hole for tightening a bolt at an opening or a split portion thereof, and the metal strip fixing block attached to the end portion of the metal strip is connected to the flange. The bolt tightening through hole provided in the metal strip fixing block and the bolt tightening through hole provided in the flange are aligned with each other while the bolt is inserted. , The terminal fixing portions of the metal reinforcing plastic tube, characterized in that to fix a metal strip fixed ring terminal metal strip by fixing it with a nut.

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