Ultrasonic level meter mounting structure

Abstract

To provide an attachment structure of an ultrasonic level meter, which prevents a malfunction of the ultrasonic level meter.SOLUTION: An ultrasonic level meter 1 is arranged on a sealed circulation tank 9. In an attachment structure of the ultrasonic level meter, spacers 2s constituted by a ring member are mediated between a flange part 98f formed on an upper surface of a detector attachment port 98 arranged on the circulation tank 9 and a flange part 1f formed in a waveguide 1c of the ultrasonic level meter 1, thereby securing ventilation with atmospheric air in the periphery of a detection part of the ultrasonic level meter 1. Thus, attachment of water droplets onto a sensor surface of an ultrasonic vibrator 1s is suppressed, which is a cause of a malfunction of the ultrasonic level meter 1.SELECTED DRAWING: Figure 1

Description

[Technical Field]

[0001] The present invention relates to a mounting structure for an ultrasonic level meter, and more particularly to a mounting structure for an ultrasonic level meter that measures the height of a liquid in a liquid tank. [Background technology]

[0002] Conventionally, an ultrasonic level meter has been known that measures the distance from an ultrasonic sensor to the liquid surface or the change in the liquid level based on the time it takes for an ultrasonic wave to be reflected from the liquid surface and received by the ultrasonic sensor after it is emitted from an ultrasonic sensor installed at the top of a liquid tank toward the liquid surface (see, for example, Patent Document 1). [Prior art documents] [Patent documents]

[0003] [Patent Document 1] Japanese Patent Application Publication No. 10-206213 Summary of the Invention [Problem to be solved by the invention]

[0004] In coal-fired power plants and other facilities, wastewater is generated from various equipment and processes, and is treated according to the characteristics of each wastewater. For example, in coal-fired power plants, a circulation tank is installed as a wastewater treatment device to purify the wastewater with chemicals. This circulation tank is equipped with an ultrasonic level meter to detect the liquid level of the wastewater inside.

[0005] 4A and 4B are diagrams showing the configuration of a circulating tank according to the present invention, in which FIG. 4A is a front view of the circulating tank, FIG. 4B is a plan view of the circulating tank, FIG. 4C is a right side view of the circulating tank, and FIG. 4D is a view taken along the arrow XX in FIG. 4B.

[0006] 4, the circulation tank 9 is provided at its top with a chemical inlet 91 through which chemicals can be introduced, an industrial water inlet 92 through which industrial water is supplied, and a liquid inlet 93 through which wastewater is supplied from another device (not shown). For example, sodium hydroxide is injected into the circulation tank 9. The circulation tank 9 is also provided at its bottom periphery with a liquid outlet 94 through which wastewater stored inside is discharged.

[0007] Referring to Figure 4, the sealed circulation tank 9 has a detector mounting port 98 at its top for mounting an ultrasonic level meter 1 (see Figure 5), which will be described later. The circulation tank 9 also has an air vent 99 at its top for releasing the air inside into the atmosphere. The detector mounting port 98 has a substantially circular flange 98f formed on its top surface (see Figure 4(D)). The detector mounting port 98 is actually a pipe member protruding from the top of the circulation tank 9.

[0008] Figure 5 is a front view showing the configuration of a mounting structure for an ultrasonic level meter according to the prior art. Referring to Figure 5, the ultrasonic level meter 1 has a display 11 provided at the top. The display 11 contains a control unit that electrically processes the signal from the ultrasonic vibrator. A waveguide made of a single pipe protrudes below the display 11. An ultrasonic vibrator (not shown) is disposed inside the waveguide.

[0009] 5, the ultrasonic level meter 1 has a substantially disk-shaped flange portion 1f formed in the middle of the waveguide. The flange portion 1f of the ultrasonic level meter 1 is fixed to a flange portion 98f of the detector mounting port 98 using a plurality of bolt members 8b and nut members 8n. The flange portions 1f and 98f are fixed in close contact with each other.

[0010] 4 and 5, ultrasonic waves are emitted from an ultrasonic vibrator provided in ultrasonic level meter 1 toward the liquid surface inside circulation tank 9, whereby the water level inside circulation tank 9 can be detected.

[0011] 4, the circulation tank 9 is connected to a drainage pump (not shown). When the ultrasonic level meter 1 detects a water level in the circulation tank 9 above a certain level, the drainage pump operates to drain the water, thereby lowering the water level in the circulation tank 9.

[0012] By the way, the drainage pump sometimes ran idly. It was discovered that the ultrasonic level meter 1 and the drainage pump were electrically connected, and the received signal from the ultrasonic level meter 1 was hunting, so the drop in water level could not be detected, and the drainage pump operation stop function did not work.

[0013] It was determined that the direct cause of hunting in the ultrasonic level meter 1 was the large amount of water droplets adhering to the sensor surface of the ultrasonic vibrator. The wastewater stored inside the circulation tank 9 was heated to about 60 degrees, so warm air was accumulating around the detection part of the ultrasonic level meter 1, causing condensation on the sensor surface of the ultrasonic vibrator, which promoted the formation of water droplets.

[0014] The ultrasonic level meter according to Patent Document 1 is said to be able to prevent malfunction of the ultrasonic level meter by providing a water-absorbent film on the inner surface of the cylindrical waveguide placed in front of the ultrasonic vibrator, so that water droplets adhering to the inner surface of the waveguide do not form droplets and are not reflected by the ultrasonic vibrator sensor when they hit the water droplets.

[0015] However, there is a problem in that it is not easy to install a new ultrasonic level meter in the existing circulation tank 9. In addition, it is necessary to change the setting values ​​of the control system, which is costly and time-consuming.

[0016] There is a need for an ultrasonic level meter mounting structure that is installed above a liquid tank and that prevents malfunction of the ultrasonic level meter by suppressing the adhesion of water droplets to the sensor surface of the ultrasonic vibrator installed inside the liquid tank without the need to replace it with a new ultrasonic level meter.

[0017] The present invention has been made in consideration of such problems, and aims to provide a mounting structure for an ultrasonic level meter that prevents malfunction of the ultrasonic level meter by suppressing the adhesion of water droplets to the sensor surface of an ultrasonic vibrator introduced inside a liquid tank. [Means for solving the problem]

[0018] The inventors have conceived an installation structure for an ultrasonic level meter installed on the top of a water tank, in which a spacer is interposed between a first flange portion formed on the top surface of the detector mounting port provided on the top of a sealed water tank and a second flange portion formed on the waveguide of the ultrasonic level meter, thereby ensuring ventilation with the atmosphere around the detection portion of the ultrasonic level meter, thereby preventing water droplets from adhering to the sensor surface of the ultrasonic vibrator. Based on this, the inventors have invented the following new installation structure for an ultrasonic level meter.

[0019] (1) The mounting structure of an ultrasonic level meter according to the present invention is a mounting structure of an ultrasonic level meter installed on the top of a sealed water tank, and a spacer is interposed between a first flange portion formed on the top surface of a detector mounting port provided on the top of the water tank and a second flange portion formed on a waveguide of the ultrasonic level meter, thereby ensuring ventilation with the atmosphere around the detection part of the ultrasonic level meter.

[0020] (2) The spacer may be made of a ring member through which a bolt member can be inserted.

[0021] (3) The mounting structure for an ultrasonic level meter according to the present invention preferably further includes a cylindrical rainwater prevention cover that covers the gap between the first flange portion and the second flange portion.

[0022] (4) It is preferable that the rainwater intrusion prevention cover is composed of a set of half-split bodies. [Effects of the Invention]

[0023] The mounting structure for an ultrasonic level meter according to the present invention interposes a spacer between a first flange formed on the top surface of the detector mounting port provided at the top of the sealed water tank and a second flange formed on the waveguide of the ultrasonic level meter, ensuring ventilation with the atmosphere around the detection part of the ultrasonic level meter, thereby preventing water droplets from adhering to the sensor surface of the ultrasonic vibrator, and thereby preventing malfunction of the ultrasonic level meter. [Brief explanation of the drawings]

[0024] [Figure 1] 1 is a front view showing the configuration of a mounting structure for an ultrasonic level meter according to an embodiment of the present invention; [Figure 2] FIG. 2 is a front view showing the configuration of the mounting structure for the ultrasonic level meter according to the embodiment, in a state before the rainwater intrusion prevention cover is attached. [Figure 3] 3A and 3B are diagrams showing the configuration of a rainwater intrusion prevention cover provided in the mounting structure of the ultrasonic level meter according to the embodiment, where FIG. 3A is a longitudinal cross-sectional view of the rainwater intrusion prevention cover and FIG. 3B is a plan view of the rainwater intrusion prevention cover. [Figure 4] 4A and 4B are diagrams showing the configuration of a circulating tank according to the present invention, in which FIG. 4A is a front view of the circulating tank, FIG. 4B is a plan view of the circulating tank, FIG. 4C is a right side view of the circulating tank, and FIG. 4D is a view taken along the arrow XX in FIG. 4B. [Figure 5] FIG. 1 is a front view showing the configuration of a mounting structure for an ultrasonic level meter according to the prior art. DETAILED DESCRIPTION OF THE INVENTION

[0025] Hereinafter, an embodiment of the present invention will be described with reference to the drawings.

[0026] [Configuration of ultrasonic level meter mounting structure] First, the configuration of the mounting structure for an ultrasonic level meter according to one embodiment of the present invention will be described. Note that components with the same reference numerals as those in the prior art have the same functions, and therefore their descriptions may be omitted below.

[0027] 1, in the mounting structure of an ultrasonic level meter according to one embodiment of the present invention, an ultrasonic level meter 1 is installed on top of a circulating tank 9, which is a sealed water tank. Referring to FIG. 1 or 2, in the mounting structure of the ultrasonic level meter, a spacer 2s is interposed between a flange portion 98f, which is the first flange portion, and a flange portion 1f, which is the second flange portion.

[0028] 1, the flange portion 98f is formed on the upper surface of the detector mounting port 98 provided in the upper part of the circulation tank 9 (see FIG. 4). The flange portion 1f is formed in the middle part of the waveguide 1c of the ultrasonic level meter 1 (see FIG. 1).

[0029] 1 or 2, a flange portion 1f of the ultrasonic level meter 1 is fixed to a flange portion 98f of the detector mounting port 98 via a spacer 2s using a plurality of bolt members 8b and nut members 8n. The flange portions 1f and 98f are fixed with a predetermined gap between them.

[0030] 1 or 2, the spacer 2s is formed of a ring member through which the bolt member 8b can be inserted. The gap between the flange portion 1f and the flange portion 98f and the gap between the waveguide 1c and the detector mounting port 98 are connected to each other, ensuring ventilation with the atmosphere around the detection portion of the ultrasonic level meter 1. The ultrasonic vibrator 1s is disposed inside the waveguide 1c (see FIG. 2).

[0031] The mounting structure of the ultrasonic level meter according to the embodiment has a spacer 2s interposed between the flange portion 98f formed on the upper surface of the detector mounting port 98 and the flange portion 1f formed on the waveguide 1c of the ultrasonic level meter 1, thereby ensuring ventilation with the atmosphere around the detection portion of the ultrasonic level meter, thereby preventing water droplets from adhering to the sensor surface of the ultrasonic vibrator 1s.

[0032] (Configuration of rainwater intrusion prevention cover) 1 or 3, the mounting structure for an ultrasonic level meter according to the embodiment further includes a cylindrical rainwater intrusion prevention cover 3. The rainwater intrusion prevention cover 3 covers the gap between the flange portion 98f and the flange portion 1f (see FIG. 1). The upper surface of the rainwater intrusion prevention cover 3 is fixed to the flange portion 1f using a nut member 8n (see FIG. 1).

[0033] 3, the rainwater intrusion prevention cover 3 is composed of a pair of half bodies 3a and 3b. One half body 3a has a strip-shaped cover piece 31 welded to its edge. The edges of one half body 3a and the other half body 3b are butted together, and the cover piece 31 covers the gap between the edges, preventing rainwater from entering the rainwater intrusion prevention cover 3.

[0034] Referring to FIG. 3, the pair of half-split bodies 3a and 3b have a plurality of bolt holes 3h on the upper surface thereof, through which the bolt members 8b can be freely inserted.

[0035] [Function of ultrasonic level meter mounting structure] Next, the operation and effect of the mounting structure for an ultrasonic level meter according to one embodiment of the present invention will be described.

[0036] The mounting structure of the ultrasonic level meter according to the present invention interposes a spacer between the first flange portion formed on the top surface of the detector mounting port and the second flange portion formed on the waveguide of the ultrasonic level meter, thereby ensuring ventilation with the atmosphere around the detection portion of the ultrasonic level meter, thereby preventing water droplets from adhering to the sensor surface of the ultrasonic vibrator.

[0037] The mounting structure for an ultrasonic level meter according to the present invention prevents malfunction of the ultrasonic level meter, thereby improving the reliability of operation and monitoring of the facility.

[0038] The mounting structure for an ultrasonic level meter according to the present invention eliminates the need to clean the sensor surface of the ultrasonic vibrator when the ultrasonic level meter hunts, thereby reducing maintenance costs.

[0039] The mounting structure for an ultrasonic level meter according to the present invention can prevent damage to the drainage pump that transports the circulating liquid.

[0040] The mounting structure for an ultrasonic level meter according to the present invention further includes a rainwater prevention cover that covers the gap between the first flange portion and the second flange portion, thereby preventing rainwater from entering the circulation tank during heavy rain, etc. [Explanation of symbols]

[0041] 1. Ultrasonic level meter 1c waveguide 1f Flange part (second flange part) 2s spacer 9 Circulation tank (water tank) 98 Detector mounting port 98f Flange part (first flange part)

Claims

1. A structure comprising a sealed water tank and an ultrasonic level meter installed on top of the water tank, A structure in which a spacer consisting of a ring member through which a bolt member can be inserted is interposed between a first flange portion formed on the upper surface of the detector mounting port of the ultrasonic level meter provided on the top of the water tank and a second flange portion formed on the waveguide of the ultrasonic level meter, thereby ensuring ventilation with the atmosphere around the detection portion of the ultrasonic level meter.

2. The structure according to claim 1 , further comprising a cylindrical rainwater prevention cover that covers the gap between the first flange portion and the second flange portion.

3. 3. The structure according to claim 2, wherein the rainwater intrusion prevention cover is composed of a pair of half-split bodies.

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