JP2010000264A - Unwinding pipe for sprinkler - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To inexpensively manufacture an unwinding pipe for a sprinkler which is easy in a piping work. <P>SOLUTION: A crosslinked polyethylene layer 3 is formed on the inner side of a thin metal pipe 2 and a polyethylene layer 4 is formed on the outer side of the thin metal pipe 2 to configure the unwinding pipe 1 for the sprinkler. Also, it is preferable that the polyethylene layer 4 on the outer side of the thin metal pipe 2 is polyethylene in which a filler for increasing flame retardancy is mixed. Further, by providing connecting pipes 6, 18S and 18L through mechanical joints 7 and 17 at both ends of the unwinding pipe 1 of the configuration, the connecting work of the unwinding pipe 1 from water supply source side piping to a sprinkler head 5 is facilitated. <P>COPYRIGHT: (C)2010,JPO&INPIT

Description

  The present invention relates to an unwinding pipe for a sprinkler, and more particularly to an unwinding pipe for a sprinkler that can facilitate the workability of piping from a header to a sprinkler head.

In general, when installing a sprinkler, a header is installed in a main pipe that is piped up to a section to be installed, and a branch pipe is provided from the header to a plurality of sprinkler heads by an unwinding pipe. Conventionally, a metal flexible pipe made of stainless steel or copper has been used for the unwinding pipe to facilitate piping.
As an example, there is a “sprinkler unwinding pipe” described in Patent Document 1. The purpose of this is to improve the ease of fine adjustment of the end of the soft copper pipe used for the sprinkler unwinding pipe and to relieve stress concentration, and the sprinkler water supply branch pipe 6 and the sprinkler head 9 Sprinkler unwinding pipe which is connected with a soft copper tube 11 and includes a bellows-like corrugated portion 12 (13) at at least one end of the soft copper tube. It is piping.

Japanese Patent Application Laid-Open No. 08-257159

However, in the case of a metal flexible tube as described above, a process of forming a bellows-like flexible part is necessary in the manufacturing process, and there is a problem of increasing costs. Moreover, since the flexible pipe has a large pressure loss during water flow, it is necessary to enlarge the pump for water supply accordingly.
Therefore, the present invention has an object to propose a sprinkler unwinding pipe that has flexibility necessary for piping without having a flexible portion, has low pressure loss during water flow, and has good workability during piping. It was.

In order to solve the above-mentioned problems, an unwinding pipe for a sprinkler according to the present invention comprises an unwinding pipe body in which a cross-linked polyethylene layer is formed inside a thin metal pipe and a polyethylene layer is formed outside the thin metal pipe, A connecting pipe connected to one end of the unwinding pipe main body through a mechanical joint and having an external thread engraved on the other end, and connected to the other end of the unwinding pipe main body via a mechanical joint to the other end. And a connecting pipe in which an internal thread is engraved.
Here, it is also possible to screw a sprinkler head onto the female screw of the connecting pipe in which a female screw is engraved at the other end.
Moreover, it is preferable that the polyethylene layer outside the thin metal tube is made of polyethylene mixed with a filler that increases flame retardancy.
Furthermore, it is also possible to apply a fireproof coating to the outer surface of the outer polyethylene layer of the thin metal tube.

As described above, according to the present invention, a cross-linked polyethylene layer is formed on the inside of a thin metal tube and a polyethylene layer is formed on the outside of the thin metal tube. Flexibility is obtained, and piping is possible without bending when bent. Further, as compared with the conventional flexible pipe, the cost can be reduced because the step of forming the flexible portion is unnecessary.
Furthermore, by providing mechanical joints at both ends, it is only necessary to twist only the connection pipe when screwing and connecting the connection pipe to the water supply source side pipe.
Furthermore, since the pressure loss during water passage is smaller than that of the flexible pipe, the water pump can be reduced in size accordingly.

Hereinafter, embodiments of the present invention will be described with reference to the drawings.
FIG. 1 is a partial cross-sectional view showing a structure of a main body portion of a sprinkler unwinding pipe.
A sprinkler unwinding tube (hereinafter referred to as unwinding tube) 1 has a structure in which a cross-linked polyethylene layer 3 is formed inside a thin metal tube 2 and a polyethylene layer 4 is formed outside the thin metal tube 2. These manufactures are performed by extrusion. The material of the thin metal tube 2 can be aluminum, copper, stainless steel, steel and alloys thereof. The unwinding tube 1 in the illustrated example has an outer diameter of 20 ± 1 mm and a wall thickness of 2.25 ± 0.5 mm.

The unwinding tube 1 has the cross-linked polyethylene layer 3 formed inside the thin metal tube 2 and the polyethylene layer 4 formed outside the thin metal tube 2, thereby increasing strength, corrosion resistance, and the like. In particular, when the unwinding pipe 1 is bent during piping, the cross-linked polyethylene layer 3 structurally supports the thin metal pipe 2 from the inside, thereby effectively preventing the thin metal pipe 2 from buckling. To work.
Furthermore, since the unwinding pipe 1 has a smaller pressure loss when passing water than a conventionally used flexible pipe, it is possible to reduce the size of the water pump.

  The polyethylene layer 4 outside the thin metal tube 2 may be general polyethylene, but it is preferable to incorporate a filler in order to improve flame retardancy and fire resistance. As the filler, glass fiber, glass beads, talc and other inorganic fillers, or organic fillers can be used as those that increase flame retardancy and fire resistance.

  Although not shown, it is preferable to apply a fireproof coating to the outer surface of the polyethylene layer 4. Specifically, for example, a paint containing ammonium polyphosphate as a main component can be applied. When a paint containing ammonium polyphosphate is applied, foaming starts when the ambient temperature reaches 200 to 300 degrees in the event of a fire, and finally foams to about 25 to 50 times, exhibiting a good heat insulating effect. .

Next, the usage pattern of the unwinding tube 1 described above will be described. FIG. 2 is a cross-sectional view showing a pipe from the water supply source side pipe to the sprinkler head, and FIG. 3 is a cross-sectional view showing a state where FIG. 2 is disassembled.
In the upper right part of the figure, two cases where the sizes of the water supply source side pipes are different are shown. 2 and 3, the sprinkler head 5 is screwed to the lower end of the connection pipe 6 on the head side. The upper end of the connecting pipe 6 is connected to the unwinding pipe 1 by a mechanical joint 7. The mechanical joint 7 includes an inner core 8 to which the unwinding tube 1 is fitted to the outside, an outer cylinder portion 9 on the outside thereof, a male screw portion 11 engraved on the outer peripheral portion of the outer cylinder portion 9, O-rings 12 and 13, The fixing ring 14 and the nut 15 are included. These are assembled in order, and the nut 15 is tightened into the male thread portion 11, whereby the unwinding tube 1 is connected to the head connection tube 6.

Next, although not shown, the unwinding pipe 1 is piped to the vicinity of the sockets 16S and 16L which are water supply source side pipes by arbitrarily curving the space under the ceiling. The other end of the unwinding pipe 1 is connected to connection pipes 18S and 18L on the water supply source side by a mechanical joint 17. The mechanical joint 17 includes an inner core 19 to which the unwinding tube 1 is fitted to the outside, an outer cylindrical portion 21 on the outer side, a male screw portion 22 engraved on the outer peripheral portion of the outer cylindrical portion 21, O-rings 23 and 24, The fixing ring 25 and the nut 26 are included.
These are assembled in order, and the unwind pipe 1 is connected to the connections 18S and 18L by tightening the nut 26 into the male screw portion 22. The other ends of the connecting pipes 18S and 18L are engraved with male screw portions 27S and 27L, and are screwed into the sockets 16S and 16L.

In the piping work at the site, either the connecting pipe 6 to which the sprinkler head 5 is screwed, the connecting pipe 18S or the connecting pipe 18L is temporarily assembled to the unwind pipe 1 in advance, and the sprinkler head 5 side is used. Or it integrates from the socket 16S, 16L side, and it pipes, curving the unwinding pipe | tube 1 to each other side suitably. When the assembly of the connecting pipe 6 and the connecting pipes 18S and 18L is completed, the nuts 15 and 26 of the mechanical joints 7 and 17 at both ends are finally tightened, and the mechanical joints 7 and 17 are completely sealed. Become.
In these operations, when connecting the connecting pipe 6 and the connecting pipes 18S and 18L, the mechanical joints 7 and 17 are not completely tightened at first, so the connecting pipe 6 and the connecting pipes 18S and 18L are A screwing operation is possible without being restrained by the unwinding tube 1. That is, a union joint that is necessary for ordinary piping is not required. As a result, the workability at the ceiling position, that is, at a high place and a narrow place is improved by the reduction of the number of parts.

It is a fragmentary sectional view which shows the structure of the main-body part of the unwinding pipe for sprinklers concerning this invention. It is sectional drawing which shows piping from a water supply source side piping to a sprinkler head. It is sectional drawing which shows the state which decomposed | disassembled FIG.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Unwinding pipe for sprinklers 2 Thin metal pipe 3 Crosslinked polyethylene layer 4 Polyethylene layer 5 Sprinkler head 6 Connection pipe 7 Mechanical joint 8 Inner core 9 Outer cylinder part 11 Male thread part 12, 13 O-ring 14 Fixing ring 15 Nut 16S, 16L Socket 17 Mechanical joint 18S, 18L Connection pipe 19 Inner core 21 Outer cylinder part 22 Male thread part 23, 24 O-ring 25 Fixing ring 26 Nut 27S, 27L Male thread part

Claims (4)

An unwinding tube body in which a cross-linked polyethylene layer is formed inside the thin metal tube and a polyethylene layer is formed outside the thin metal tube;
A connecting pipe connected to one end of the unwinding pipe main body through a mechanical joint and engraved with a male screw at the other end;
A connecting pipe connected to the other end of the unwinding pipe main body via a mechanical joint and engraved with an internal thread at the other end;
A sprinkler unwinding tube characterized by comprising: In the unwinding pipe for sprinklers of Claim 1,
A sprinkler unwinding pipe, wherein a sprinkler head is screwed onto the female thread of a connecting pipe having a female thread at the other end. The sprinkler unwinding pipe according to claim 1 or 2,
The sprinkler unwinding pipe, wherein the polyethylene layer outside the thin metal pipe is made of polyethylene mixed with a filler that increases flame retardancy. The sprinkler unwinding pipe according to any one of claims 1 to 3,
A sprinkler unwinding pipe, wherein a fireproof paint is applied to an outer surface of a polyethylene layer outside the thin metal pipe.

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