JPH0652850U - Piping material for sprinkler - Google Patents

Abstract

(57) [Abstract] [Purpose] To provide a sprinkler pipe material capable of preventing deformation of a copper pipe, reducing troublesome work such as replacement of a deformed copper pipe, and preventing electrolytic corrosion. [Structure] In a sprinkler piping material used for piping of a fire extinguishing sprinkler system, a spiral coil 2 is fitted on an outer surface of a copper pipe 1. This coil 2 is made of metal, and its surface is metal-plated or resin-coated.

Description

[Detailed description of the device]

[0001]

[Industrial applications]

 The present invention relates to a pipe material for a sprinkler used for a sprinkler piping system in a fire extinguishing facility of a building.

[0002]

[Prior art]

 Conventionally, it is known to use a copper pipe as a piping material for a fire extinguishing sprinkler. The demand for copper pipes has been increasing in recent years due to their excellent corrosion resistance, light weight, and good workability. In addition, it may be necessary to finely adjust the mounting position of the head adapter mounted on the ceiling from the viewpoint of improving the appearance after the completion of the sprinkler construction. For this reason, in the unwinding pipe, a soft copper pipe is used, which can easily cope with the fine adjustment of the mounting position of the head adapter. The unwinding pipe is a pipe of a portion where the pipe diameter is gradually reduced from a large-diameter pipe and is finally connected to the head adapter. Usually, this unwinding piping work consumes a lot of man-hours in a series of piping work and is troublesome.

As described above, it is necessary to bend a copper pipe in order to perform fine adjustment of the pipe. However, when performing the bending work at a pipe construction site, a special tool is used as a characteristic peculiar to the copper pipe. Even if it is used, the copper pipe may be flat, or in extreme cases, buckling may occur. In addition, there is a risk that the copper pipes that have been installed may be damaged if other work such as electrical work is performed after the completion of the pipe installation.

When the pipe is flattened, the problem that the required amount of water defined by the law cannot be ensured simply occurs, and stress is concentrated on the deformed portion, which may cause stress corrosion cracking. There is. If the pipe buckles, it can no longer be used as a pipe.

Since hard copper pipes are more difficult to bend than soft copper pipes, when used as unwinding pipes, they are used in piping systems that use many joints. For this reason, it is difficult to finely adjust the mounting position of the hard copper pipe, and the main component of the unwinding pipe is the soft copper pipe.

[0006]

[Problems to be solved by the device]

 As mentioned above, soft copper pipes have the advantage of good workability because they are easy to bend, so they have come to be widely used as sprinkler pipes that do not use joints, but they have excellent bendability. However, there is a drawback in that the flattening phenomenon or buckling of the pipe cannot be avoided during bending. For example, a small-diameter soft copper tube with a nominal diameter of about 20 A (outer diameter of about 20 mm) has a small flatness even if the radius of curvature is as large as 300 mm. Further, the flatness increases as the radius of curvature becomes smaller, and buckling easily occurs when the radius of curvature is 100 mm or less.

On the other hand, in the on-site piping work, the work situation tends to be rough, and various equipment and members may come into contact with the pipe material not only during the sprinkler piping work but also after the completion of the pipe installation. It always happens. Depending on this contact situation, the copper pipe is damaged.

Further, when the copper pipe comes into contact with the metal member, a stray current of the building may flow into the copper pipe, which may cause electrolytic corrosion that corrodes the outer surface of the pipe.

The present invention has been made in view of the above problems, and can prevent deformation of a copper pipe, reduce troublesome work such as replacement of a deformed copper pipe, and prevent electrolytic corrosion. The purpose of the present invention is to provide a piping material for a sprinkler.

[0010]

[Means for Solving the Problems]

 The sprinkler pipe according to the present invention is characterized in that, in the sprinkler pipe material used for the pipe of the fire extinguishing sprinkler system, a spiral coil is fitted on the outer surface of the copper pipe.

[0011]

[Action]

 In the present invention, since the coil is fitted on the outer surface of the copper pipe and fixed to the copper pipe, the rigidity against deformation in the cross section of the copper pipe is increased, and the flat deformation of the copper pipe is performed during bending. It is possible to prevent it, and it is possible to avoid the occurrence of buckling.

There are various types of materials for the coil, such as stainless steel, carbon steel, and copper alloy. However, the stainless steel coil may corrode the copper pipe during long-term use due to an electrochemical reaction. Also, if a copper alloy is selected as the coil material, there is no risk of corrosion, but there is a cost problem. Therefore, carbon steel is used as the coil material, and the surface of the coil is metal-plated or resin-coated to reduce costs and prevent corrosion.

As for the resin coating material, there is no limitation on the material to be used, but it is preferable to use a material having a property of being difficult to burn or a material which does not generate a harmful gas even when it is burned.

Zinc plating is an example of metal plating, and nylon resin is a resin coating material.

[0015]

【Example】

 Hereinafter, embodiments of the present invention will be described in detail with reference to the accompanying drawings.

FIG. 1 shows a pipe 10 in which the head adapter 3 is installed in an L-shaped sprinkler pipe. Long ceiling support members 5 and 6 having a U-shaped cross section are fixed at intersections orthogonal to each other and are installed in a grid pattern, and the ceiling board 4 is supported by these support members 5 and 6. It is arranged.

Further, the L-shaped head adapter 3 is fixed to the support member 5 by a stopper 8. A sprinkler head 7 is attached to the lower end of the head adapter 3, and the sprinkler head 7 is arranged so that its ejection end is directed toward the room through an opening provided in the ceiling board 4.

The main pipe 9 of the fire extinguishing water and each sprinkler head 7 are connected by the pipe 10 of this embodiment via the head adapter 3. The pipe 10 has a soft copper pipe 1 and a spiral coil 2 fitted on the outer surface thereof. The pipe 10 is bent at the piping site so as to connect the main pipe 9 and the head adapter 3 together.

The copper pipe 1 of the pipe 10 and the metallic coil 2 are usually not fixed, and have a gap of 0.1 to 0.3 mm. If both are fixed, it will be difficult to bend the copper pipe, and the connection with the head adapter at the end will be troublesome. The surface of the coil 2 is galvanized. The surface of the coil 2 may be resin-coated.

Next, the operation of the sprinkler piping material configured as described above will be described. When a soft copper pipe is bent so that local buckling does not occur, the copper pipe is flattened over the entire processed portion under normal conditions. For example, in the case of a copper tube with a nominal diameter of 20 A, the minimum radius of curvature that does not cause buckling is 150 mm, and the flat area at that time reaches about 470 mm in L-shaped (90 degrees) bending.

In order to suppress this flattening deformation, it is necessary to have a restraining force for restraining the pipe at both ends of the pipe in a direction perpendicular to the surface including the pipe after bending. That is, when the cross section of the pipe is bent into an ellipse when it is bent, if the increase in the major axis in this ellipse can be suppressed by the restraining force, the decrease in the minor axis can be prevented. One of the functions of the metal coil is to suppress the increase in the major axis. In order to suppress the elongation (that is, flattening) of the piping material in the major axis direction, the metal coil preferably has a wire diameter of 0.8 to 2.0 mm and a pitch of 1 to 15 mm. If the wire diameter is smaller than 0.8 mm, the strength of ordinary metal materials is insufficient, and the elongation of the copper pipe in the major axis direction cannot be suppressed. If it is thicker than 2.0 mm, bending work becomes difficult. On the other hand, if the pitch is too narrow, the entire pipe becomes rigid and bending becomes difficult. Therefore, the pitch of the coil is preferably 1 mm or more in order to take advantage of the advantages of the soft copper tube. On the contrary, if the coil pitch exceeds 15 mm, local buckling is likely to occur in the gap. Therefore, the pitch of the coils is preferably 15 mm or less.

If other members come into contact with the copper pipe, the copper pipe is damaged depending on the degree of contact. There are various types of damage, such as scratches, buckling, and flatness, and the damage caused by contact is generally heavier than the damage caused during bending. The second function of the metal coil is to greatly reduce the chance of other members coming into contact with the copper tube. The narrower the wire pitch of the metal coil, the better. However, if it is 1 mm or less, bending becomes difficult, and if it is 10 mm or more, the possibility of contact increases rapidly.

For this reason, the coil pitch is preferably 1 to 10 mm from the viewpoints of both preventing contact with other members and preventing flattening.

There are various members that come into contact with each other, and although they may be made of resin, most of them are made of metal, and contact with the metallic members may cause electrolytic corrosion. However, when a resin coating is applied to the metal coil, even if a stray current flows, it can be insulated. Further, in the galvanized coil, the sacrificial anodic action of zinc can protect the coil and the copper tube from various corrosion reactions.

The embodiment shown in FIG. 1 is provided with an L-shaped head adapter 3, and can be installed even when the space above the ceiling is relatively small.

On the other hand, in the embodiment shown in FIG. 2, the straight type head adapter 11 is attached to the support member 6 of the ceiling board 4. In this embodiment, the main pipe 9 of the fire extinguishing water is arranged at a high position above the ceiling, and the pipe 10 is used when it is unwound from the high position.

Next, the results of a test for manufacturing the sprinkler piping material according to the embodiment of the present invention and comparing the effect thereof with the comparative example will be described. Test 1 Specimen: Example 1: After coating the outer surface of a soft copper pipe with a nominal diameter of 20 A with a thickness of 100 μm, a coil of high carbon steel with a wire diameter of 1.5 mm and a pitch of 5 mm was used. Wrapped around. The length of this test material is 1 m.

Comparative Example 1: A single soft copper tube having a nominal diameter of 20 A and a length of 1 m. Test method: Assuming a case in which one end of the test material is fixed and the other end is connected to a head adapter 700 mm apart, using the piping model in Fig. 1, L-shaped bending with a radius of curvature of 200 mm, and bending I observed the situation. Test results: After the test piping work was completed, the test materials were removed and the damage conditions of the pipes were investigated. The results shown in Table 1 below were obtained.

[0029]

[Table 1] However, as shown in FIG. 3, the roundness was calculated by the following mathematical formula 1 with D ₀ being the average diameter before processing, D ₁ being the major diameter after processing, and D ₂ being the minor diameter after processing.

[0030]

## EQU1 ## Roundness = (D ₁ −D ₂ ) / D ₀

Test 2 Example 2 was prepared as in Test 1. However, there are various lengths of 1 to 2.5 m. Comparative example 2 is similar to comparative example 1. Test method: Applied to a new real property, one year after the completion of construction, we entered the ceiling and confirmed the situation. The property is a building for commercial purposes, and there was a remodeling during the test year, and construction inside the ceiling was performed. Test Results: Comparative Example 2: 7% of the number of test objects is considered to have no practical problem, but some damage was observed. The electrolytic corrosion phenomenon did not occur.

Example 2: When the coil was shifted and checked over the entire length of the test material, no damage including electrolytic corrosion was observed. Test 3 The product of the present invention has a combined structure of a metal coil and a copper tube, and is a product used in various environments, so it is possible that contact corrosion due to dissimilar metals may occur. Therefore, various corrosion tests were conducted as shown in Table 2 below. A copper tube with a coated coil is a carbon steel coil with nylon resin coating on the peripheral surface. The galvanized metal coil can be expected to have the above-mentioned anticorrosion effect, so the test was not conducted. For comparison, corrosion tests were also performed on the copper tube alone and the uncoated carbon steel coil exposed.

SO ₂ gas test: SO ₂ concentration; 10 ppm, temperature; 40 ° C., humidity; 95% RH salt spray test: NaCl concentration; 5%, spray amount; 3.8 liters / day, humidity; 35% wetness test: temperature 40 ° C., humidity; 98% RH or higher. The test results are shown in Table 2 below.

[0034]

[Table 2]

As is clear from Table 2, corrosion can be suppressed by coating the coil with the nylon resin coating. On the other hand, when the carbon steel coil was used without coating, iron rust occurred and corrosion became a problem.

[0036]

[Effect of device]

 As described above, the present invention is slightly higher in cost than the single copper tube, but the possibility of damaging the copper tube is greatly reduced, the reliability is significantly improved, and the present invention is Even if the pipe is bent in the field, its cross section does not become flat and buckling can be prevented, so the work of dedicated bending using a tool in a narrow space inside the ceiling is complicated. Is eliminated and, as a result, workability is significantly improved.

[Brief description of drawings]

FIG. 1 is a schematic view showing piping that is used when a space above a ceiling is relatively small and that is connected to an L-shaped head adapter.

FIG. 2 is a schematic view showing a pipe used for unwinding from a high position and which is connected to a straight head adapter.

FIG. 3 is a diagram showing dimension measurement positions for roundness calculation.

[Explanation of symbols]

 1; Copper pipe 2; Coil 3, 11; Head adapter 4; Ceiling board 5, 6; Ceiling support member 7; Sprinkler head 10; Sprinkler piping

 ─────────────────────────────────────────────────── ─── Continuation of the front page (72) Shigeru Kyohara 14-1 Nagafu Minatomachi, Shimonoseki City, Yamaguchi Prefecture Inside the Kobe Steel Co., Ltd. Chofu Works (72) Inventor Shigehiro Iwanaga 4, 6 Wakaetocho, Higashiosaka, Osaka No. 58 Taku Manufacturing Co., Ltd.

Claims (2)

[Scope of utility model registration request] 1. A sprinkler piping material used for piping of a fire extinguishing sprinkler system, wherein a spiral coil is fitted on the outer surface of a copper pipe. 2. The sprinkler piping material according to claim 1, wherein the coil is made of metal and the surface of the coil is metal-plated or resin-coated.