JP3168831B2 - Metal drain pipe - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a metal drain pipe for a high-rise building.

[0002]

2. Description of the Related Art Generally, metal pipes such as cast iron pipes and steel pipes or synthetic resin pipes made of vinyl chloride resin are used as drain pipes for buildings. However, most drain pipes for high-rise buildings such as hotels and condominiums are metal pipes because they are weak in synthetic resin pipes. For this reason, the sound of falling when solids or liquids fall through toilet drain pipes or the like has become a major problem as noise in hotels and condominiums where people live.

In order to prevent such noise, Japanese Patent Application Laid-Open No. 4-73484 discloses that a metal outer tube is made of a synthetic resin such as polyethylene while maintaining a predetermined gap between the outer tube and the outer tube. A sound-absorbing resin-lined drainage composite pipe has been proposed in which an inner pipe is inserted, and the gap between the outer pipe and the inner pipe is densely filled with a urethane-based synthetic resin foam. I have.

[0004]

However, in such a lining tube, there is a limit in increasing the thickness of the inner tube or foam made of a synthetic resin, and the thicker the thickness is, the more the noise reduction performance cannot be effectively utilized. . When the noise level of the drainage noise was actually measured using the above-mentioned commercially available lining pipe, no great noise reduction effect was obtained. In addition, since the outer surface is metal, there is a problem that a loud noise is generated when an object hits from the outside, and the cost is high due to a complicated manufacturing method.

The present invention has been made to solve such a problem, and has excellent sound insulation performance against drainage noise and the like.
Moreover, it is an object of the present invention to provide an inexpensive metal drain pipe with a simple manufacturing method.

[0006]

The object of the present invention is that the outer peripheral surface is made of a porous material having a density ρ of 0.5 g / cm ³ or less, the coating thickness t is 0.1 cm or more, and ρ−0.3 × t ≦
A first coating layer satisfying 0.2, external to the density ρ of the target film layer is made of 0.9 g / cm ³ or more materials, coating thickness t
Is not less than 0.005 cm and a second coating layer satisfying ρ × t ≧ 0.05 is provided.

[0007]

The basic idea of the present invention is to provide a first coating layer having high sound absorption performance on the outer peripheral surface of a metal tube and to provide a second coating layer having high performance for preventing sound transmission thereon to improve sound insulation performance. To make it happen.

It is well known that a porous material having a low density is desirably used as a material having a high sound absorbing performance for use in the first coating layer. Then, it was examined using foamed polystyrene whether or not a desired noise reduction effect was obtained. At this time, the second coating layer had a density of 0.95 g / cm ³ and a coating thickness of 0.06 g / cm ^3.
cm of polyethylene, and the noise level was measured using the apparatus shown in FIG. In FIG. 3, reference numeral 1 denotes a drain pipe as a test material, 2 denotes a toilet bowl, and 3 denotes a sound level meter. JISC1502
The described noise level, that is, the A-weighted sound pressure level is measured, and if the value is smaller than the measured value of the bare metal pipe without the first and second coating layers by 5 dB or more, a level that does not substantially cause a problem as noise. Therefore, whether or not the difference from the measured value of the bare metal tube was 5 dB or more was used as an evaluation criterion for the noise reduction effect. FIG. 1 shows the noise level measurement results when the density ρ and the coating thickness t of the first coating layer made of expanded polystyrene were changed.
Shown in The density ρ is 0.5 g / cm ³ or less, the coating thickness t is 0.1 cm or more, and ρ−3 / 10 × t ≦ 2/1.
It can be seen that a sound reduction effect of 5 dB or more can be obtained within the range of the oblique line in FIG.

As a porous material having a low density, besides expanded polystyrene, glass wool, rock wool, calcium silicate, expanded urethane, expanded polyethylene, expanded polypropylene and the like can be used. The result was almost the same as the result. The reason why polyethylene was selected as the second coating layer is that the density is 0.95 g / cm ³ , which is one of the most disadvantageous materials in terms of the sound transmission preventing performance. That is, if polyethylene can provide a sound reduction effect of 5 dB or more, even if another material within the scope of the present invention is used as the second coating layer, a sound reduction effect of 5 dB or more is always obtained.

In order to improve the sound transmission preventing performance by the second coating layer, the coating layer may be selected so as to increase the weight per unit area. That is, if a material having a high density is used and the film thickness is increased as much as possible, the sound transmission preventing performance is improved. However, providing a material having a high density unnecessarily thick increases the weight of the product and increases the cost. Therefore, it was examined by using a material having various densities and changing a film thickness of the material having various densities ρ to obtain a noise reduction effect of 5 dB or more. In order to change the density, low foam polyethylene (ρ: 0.7g
/ Cm ³ ), polyethylene (ρ: 0.95 g / c)
m ³ ), vinyl chloride (ρ: 1.4 g / cm ³ ), aluminum (ρ: 2.7 g / cm ³ ), iron (ρ: 7.8 g / cm ³ )
cm ³ ), copper (ρ: 8.9 g / cm ³ ), lead (ρ: 1
1.3 g / cm ³ ) of the material. At this time, the first coating layer has a density of 0.32 g / cm ³ and a coating thickness of 0.5 c.
m of expanded polystyrene was used. The method of measuring and evaluating the noise level is the same as the method used in the examination of the first coating layer. FIG. 2 shows the noise level measurement results when the density ρ of the second coating layer and the coating thickness t were changed using various materials. When the density ρ is 0.9 g / cm ³ or more and the coating thickness t is 0.005
It can be seen that a noise reduction effect of 5 dB or more can be obtained within a range of hatched lines in FIG.

Although the expanded polystyrene is used for the first coating layer, the same result as that of the expanded polystyrene shown in FIG. The result was obtained.

In the present invention, since the coating layer is provided on the outer peripheral surface of the metal tube, the thickness of the coating layer does not affect the inner diameter of the metal tube. Therefore, the flow rate can be secured as compared with a metal pipe having a coating layer on the inner surface, and thick coating can be performed as necessary. Furthermore, since there is a coating layer on the outer peripheral surface, it is possible to partially change the coating layer and to easily repair the coating layer if necessary.

Even if a coating such as vinyl chloride or tar epoxy is provided on the inner peripheral surface of the metal tube for corrosion protection, the effect of the present invention is of course not impaired.

[0014]

[Example] Nominal diameter 80A, length 5500mm, wall thickness 2.
Samples were prepared by sequentially providing various first coating layers and second coating layers shown in Table 1 on the outer peripheral surface of a 3 mm steel pipe (JIS G3452), and the A-characteristic sound pressure level was measured by the method shown in FIG. . In addition, a bare steel pipe without first and second coating layers (N
o. The A-weighted sound pressure level of 31) was also measured and used as a reference value.
No. Reference numeral 32 denotes a commercially available product of the same size.
This is a 0 mm vinyl chloride pipe lined. Table 2 shows the measurement results of the A-weighted sound pressure level of each sample.
If a material having a density and a coating thickness within the range of the present invention is selected for the first coating layer and the second coating layer, a sound reduction effect of 5 dB or more can be obtained as compared with a bare steel pipe without these coating layers. The commercially available product had only a 2 dB noise reduction effect.

[0015]

[Table 1]

[0016]

[Table 2]

[0017]

Since the present invention is configured as described above, it is possible to provide an inexpensive metal drain pipe which is excellent in sound insulation performance against drainage noise and the like, is simple in manufacturing method, and is inexpensive.

[Brief description of the drawings]

FIG. 1 is a diagram showing a relationship between a density ρ of a first coating layer, a coating thickness t, and a range in which a noise reduction effect of 5 dB or more can be obtained.

FIG. 2 is a diagram showing a relationship between a density ρ of a second coating layer, a coating thickness t, and a range in which a noise reduction effect of 5 dB or more can be obtained.

FIG. 3 is a diagram illustrating a method of measuring a noise level of a drain pipe.

Claims (1)

(57) [Claims] 1. An outer peripheral surface made of a porous material having a density ρ of 0.5 g / cm ³ or less, a coating thickness t of 0.1 cm or more, and satisfying ρ−0.3 × t ≦ 0.2. a first coating layer, and external to the density [rho of the target layer is from 0.9 g / cm ³ or more materials, coating thickness t is not less than 0.005 cm, and satisfies the [rho × t ≧ 0.05 A metal drain pipe provided with a second coating layer.