JP2008064209A - Drain trap with thermo-label and its inspection method - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To easily and inexpensively inspect a number of drain traps in a short period of time by easily displaying the surface temperatures of the drain traps to be immediately and visually determined. <P>SOLUTION: On the outer surface of the drain trap 1, a material 4 is provided whose color is changed according to its temperature. The existence of change of the color is observed to determine a failure. The material 4 is preferably color-changeable at 50°C or lower and preferably a thermo-label having at least a region 43 where it is color-changeable at 50°C or lower. The thermo-label is preferably provided near a drain inlet 2 of the drain trap. At least one layer of transparent film may be laminated thereon. <P>COPYRIGHT: (C)2008,JPO&INPIT

Description

  The present invention relates to a drain trap that can easily determine whether or not it is operating normally, and a drain trap inspection method.

  In facilities such as power plants and buildings that use steam as a heat source, drain generated in the steam piping system that transports steam needs to be quickly discharged from the steam piping system in order to increase operating efficiency. . Therefore, drain traps (also called “steam traps”) are installed everywhere in the steam piping system.

  The drain trap is configured to open and discharge the valve when drain is generated, while closing the valve so as not to leak steam when drain is not generated. It is configured to operate intermittently so as to open the valve and discharge the drain at every time interval when a certain amount of drain accumulates, or to operate continuously so that the drain is dripped substantially constantly. ing.

  However, rust and dirt exist inside the steam piping system, and when this accumulates in the drain trap valve, the valve is closed and drainage is not discharged. If the drain is no longer discharged, the operation efficiency is lowered and the facility operation is hindered. Therefore, it is necessary to periodically check whether the drain trap is operating normally.

  When the drain trap valve is closed, drain accumulates inside the drain trap, and the temperature of the drain trap decreases. Therefore, whether the drain trap is operating normally is usually determined by touching the outer surface of the drain trap with your hand to check the temperature, or by auscultating the drain trap with a stethoscope. It is carried out by a method such as checking whether or not drain is accumulated by checking, or visually confirming the state of drain discharge when draining.

  However, in a large-scale facility such as a power plant, an infinite number of drain traps are provided, and it takes a lot of labor and time to check all the drain traps by the method described above. Also, the drain trap is often provided in a narrow place where it cannot be easily approached.

  In view of this, an apparatus has already been proposed in which the temperature of the outer surface of the drain trap is detected by detecting the intensity of infrared rays emitted therefrom and the temperature of the drain trap can be checked in a non-contact manner (Patent Documents 1 and 2). reference). However, this apparatus has a complicated configuration with a built-in computer, and is expensive.

Japanese Patent No. 2954183 JP 2001-324389 A

  An object of the present invention is to display the temperature of the surface of the drain trap in a simple manner so that it can be visually judged immediately, so that a number of drain traps can be inspected easily and inexpensively in a short time. There is.

According to one aspect of the present invention, the above object is achieved by a drain trap characterized in that the outer surface is provided with a material whose color changes with temperature, preferably a thermolabel.
According to another aspect of the present invention, the above object is characterized in that a material whose color changes with temperature, preferably a thermo label, is provided on the outer surface of the drain trap and the color change is observed. This is achieved by checking the drain trap.

  In the present invention, the drain trap is not particularly limited. For example, a mechanical drain trap that opens and closes a valve by a float provided inside, a disk type drain trap provided with a disk type valve inside, a bimetal, or a temperature-sensitive liquid. And a thermostatic drain trap that uses a bellows or element that encloses the valve to open and close the valve. These drain traps may be temperature control traps that can arbitrarily set the temperature of the discharged drain.

  In the present invention, the material whose color changes depending on the temperature is not particularly limited, and examples thereof include special inks and paints that change color according to the temperature, and thermo labels. The thermo label is preferable. In a normal steam piping system, the temperature of the outer surface of the drain trap is 90 to 130 ° C. during normal operation. However, if the drain trap valve closes and malfunctions, The temperature only rises to about 45 ° C. Therefore, the material is preferably a material that changes color when the temperature is 50 ° C. or lower. The material may be a material whose color changes reversibly with temperature or a material whose color changes irreversibly with temperature, but the latter is preferred. The thermolabel generally includes a plurality of regions that change at different temperatures, but preferably includes at least a region that changes color when the temperature is 50 ° C. or less, and can determine the degree of failure of the drain trap. In order to do so, in addition to the region that changes color when it becomes 50 ° C. or lower, at least a region that changes color when it becomes 60 ° C. or lower and / or a region that changes color when it becomes 70 ° C. or lower Is more preferable.

In the present invention, the material such as a thermo label is preferably provided in the vicinity of the drain inlet of the drain trap. This is because the vicinity of the inlet is where the temperature changes most greatly between when the drain trap valve is normal and when it fails.
In the present invention, the material such as a thermo label is preferably laminated with one or more transparent films thereon. By laminating with a transparent film, it is possible to prevent the material such as a thermo label from being deteriorated by wind and rain or from adhering dust. When the transparent film is laminated in multiple layers, the discoloration can be accurately confirmed in a dust-free state at all times by peeling off the outermost film at every inspection.

  According to the present invention, since the material whose color changes with temperature is provided on the outer surface of the drain trap, the color of the material automatically changes when the drain trap valve fails and its temperature changes. So you can see the change at a glance. Therefore, even in a large-scale plant such as a power plant where a large number of drain traps are installed, it is possible to easily inspect a large number of drain traps in a short time. In addition, in existing equipment, the drain trap can be inspected at low cost simply by providing a material such as a thermolabel that changes its color on the outer surface of the drain trap.

  Hereinafter, although the specific example of this invention is demonstrated based on drawing, this invention is not limited only to the following specific example.

  FIG. 1 is a side view schematically showing an example of the drain trap of the present invention, and shows an example in which a disk type drain trap is used as the drain trap. In FIG. 1, numeral 1 generally indicates a drain trap, numeral 2 indicates a drain inlet, and a steam pipe 20 of a steam piping system is connected to this. Reference numeral 3 denotes a drain outlet, to which a drain pipe 30 connected to a drain tank (not shown) is connected.

  A thermo label 4 is attached to the outer surface of the drain trap 1 so as to be adjacent to the drain inlet 2. This thermolabel 4 has three different regions, which are, in order from the drain outlet direction, a region 41 that changes color below 70 ° C., a region 42 that changes color below 60 ° C., and a region 43 that changes color below 50 ° C. I have.

  In the drain trap 1 of FIG. 1, when the drain is not accumulated in the steam pipe 20, the valve in the drain trap 1 is closed and the circulation of the steam to the drain outlet 3 is prevented. However, when drain is accumulated in the steam pipe 20, the valve in the drain trap 1 is opened in response to a slight decrease in the temperature of the drain trap 1, and the drain is discharged to the drain outlet 3.

  However, when the drain trap 1 of FIG. 1 fails, even if drain is accumulated in the steam pipe 20, the valve in the drain trap 1 does not open, and the drain is in the drain trap 1 and the steam pipe 20 near the drain inlet 21. Accumulate in In this case, the temperature of the outer surface of the drain trap 1 gradually decreases and finally decreases to 50 ° C. or lower.

  In the drain trap of the present invention, as shown in FIG. 1, since the thermo label 4 is attached to the outer surface of the drain trap 1, it is confirmed that the temperature of the drain trap has dropped due to a failure. It can be judged by discoloration. Since the thermolabel of FIG. 1 includes three types of areas 41, 42, and 43, the degree of the temperature drop of the drain trap 1 can be determined. For example, when only the area 41 changes color, "When the areas 41 and 42 are discolored, it is also possible to make a determination such as" Discharge failure ", and when the areas 41, 42 and 43 are discolored," failure ". As shown in FIG. 1, the thermo label 1 is a portion of the outer surface of the drain trap 1 where the temperature change is most likely to appear due to a valve failure, that is, the outside adjacent to the drain flow path inside the drain trap 1. It is preferable to provide a side surface adjacent to the drain inlet 20 so that the color changing regions 41 to 43 are located.

  As the thermolabel 4 shown in FIG. 1, a commercially available one can be used as it is, and the drain trap can be easily inspected by simply attaching the thermolabel 4 to the outer surface of the existing drain trap 1. It becomes like this. Needless to say, the drain trap 1 having a thermolabel attached in advance to the outer surface may be installed and used.

  When the thermolabel 1 is attached to the outer surface of the drain trap 1, the surface of the thermolabel 1 is used to prevent dust from adhering to the thermolabel 1 over time and making it difficult to observe discoloration during inspection. A transparent plastic film (not shown) may be laminated. In this way, when it is difficult to observe the discoloration of the thermo label 1 due to the adhesion of dust during inspection, the discoloration can be observed by peeling the plastic film. The transparent plastic film may be laminated in multiple layers. In this case, the thermolabel 1 can be accurately observed by peeling off the outermost plastic layer at every inspection.

  The present invention is a technique useful in facilities such as a power plant, a factory, and a building provided with a steam piping system equipped with a drain trap.

The schematic side view shown in the state connected to the steam piping system of an example of the drain trap of this invention.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 ... Drain trap, 2 ... Drain inlet, 3 ... Drain outlet, 4 ... Thermo label, 41, 42, 43 ... Color change area, 20 ... Steam pipe, 30 ... Drain pipe.

Claims (6)

A drain trap comprising a material (4) whose color changes with temperature on an outer surface. The drain trap according to claim 1, wherein the material (4) whose color changes with temperature is a material (43) that changes color when it becomes 50 ° C or lower. The drain trap according to claim 2, wherein the material (4) whose color changes with temperature is a thermolabel (4) having at least a region (43) which changes color when it becomes 50 ° C or lower. The drain trap according to claim 3, wherein the thermolabel (4) is provided in the vicinity of a drain inlet (2) of the drain trap. The drain trap according to any one of claims 2 to 4, wherein the thermolabel (4) has one or more transparent films laminated thereon. A drain trap inspection method comprising: providing a material (4) whose color changes with temperature on an outer surface of the drain trap (1), and observing whether or not the color changes.

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