JPH02154132A - Air leak detector for negative pressure part - Google Patents

Abstract

PURPOSE:To detect a leak from a gap generated at the negative pressure part of turbine facilities securely and speedily by providing a cup-shaped wind collection part almost whose opening part periphery can be along the surface of an objective part to be measured. CONSTITUTION:When the wind collection part 1 is applied to the coupling part of the flanges A1 and B1 of a condenser A to be measured and a low- pressure turbine B by using a detector, a wind collection part main body 11 made of magnetic rubber is sucked to the flanges A1 and B1 and a filler material 12 is charged in the space formed of the flanges A1 and B1, rubber packing C, and wind collection part main body 11. Therefore, if there is a gap formed at the position where the wind collection part 1 is applied, converged air which passes through a fine wind speed detector 3 and a space passage 2 leaks in the part to be measured from the gap. Consequently, only the flow of converged air and the flow of air leaking to the gap pass through the fine wind speed detector 3, so the detection accuracy is not affected by the flow of air due to other factors and the presence of the gap can be confirmed.

Description

DETAILED DESCRIPTION OF THE INVENTION [Industrial Application Field 1] The present invention is mainly used in power plants to detect air leakage into turbine equipment whose internal pressure is negative, such as a condenser. The present invention relates to an air leak detection device used.

[1; t = Next technology] In the turbine equipment of power plants, the work in the low-pressure turbine is increased by creating a negative pressure on the steam side by utilizing the density difference between steam and water. In addition, negative pressure sections were formed in several other places, including the condenser, which leaked 1 liter of air using a vacuum pump and released 4 JU of the trapped air to maintain a negative pressure state. There is.

However, for some reason, gaps may form in the outer walls surrounding these negative pressure parts, and when such gaps occur, air is sucked through the gaps, damaging the vacuum on the negative pressure part side and reducing the power generation output. A problem arises in that the determined steam pressure cannot be set high, resulting in a decrease in ripening efficiency.

For this reason, various methods have been attempted since then to detect the occurrence of the above-mentioned gap; for example, methods such as an air flow detection method and a halogen method are known.

Among these methods, the air flow detection method uses smoke from incense sticks, etc.
By looking at the fact that the flow of the smoke on the atmospheric side changes under the influence of the air sucked in between 1.1 and lfj+1 near the surface of On the other hand, in the halogen method, halogen gas is released outside 1(nj) of the measurement target part, and when this halogen gas is detected at the outlet of the vacuum pump, there is a gap in the i+j+ constant target part. This is to detect that something is occurring.

[Problems to be Solved by the Invention] However, the reliability of the air flow detection method for detecting air leakage is extremely low, and the reality is that it is hardly used in practice.

On the other hand, with the halogen method, it is not possible to detect halogen gas until a long period of time has passed after it is released, and once the halogen gas has entered the measurement target, it takes a long time to release it. There is a problem in that a large amount of time must be spent on the detection work.

As described above, the general methods known since then have had major problems with detection accuracy or speed, and there is currently a need for the development of a means to solve these problems. For example, in recent years, the ultrasonic waves generated when air leaks from the above-mentioned gap are 11JL in total.
An ultrasonic detection method for detecting the occurrence of the gap has been proposed. However, this ultrasonic detection method also
Although it is possible to detect leakage relatively reliably if the wall where the gap occurs is thin, leakage cannot occur in areas with large wall thickness, which is the case in most of the parts to be measured. The reality is that it is almost impossible to detect and is not practical.

The present invention has been developed in view of the above-mentioned circumstances +11, and is mainly used in power plants to prevent leakage from gaps occurring in the negative pressure section of the turbine installation, including condensers. The object of the present invention is to provide an air leakage detection device in a negative pressure section that can reliably and quickly detect air leakage.

As a result of intensive research, the inventor of the present application found that the problem with the air flow detection method described above is: The airflow on the atmospheric side is so small that it is difficult to visually detect it, ■1l
In many cases, there are atmospheric flows caused by other factors, such as updrafts around the condenser, in the area to be fixed. They discovered that this makes it more difficult to detect, and based on this they came to construct the following means.

[Means for Solving the Problems] In order to achieve the above object, the air leak detection device for a negative pressure part according to the present invention has a cup-shaped air collecting part main body whose opening periphery can be substantially aligned with the surface of the measurement target part. an air collector having a wind collector, an air passage connected to the main body of the air collector, and detecting air leaking from the measurement target part to the negative pressure side inside the part through the passage, and detecting that the wind speed of this air is above a predetermined value. It is characterized by comprising a slight wind speed detector that generates a detection signal at certain times.

By doing the above, when the periphery of the wind collecting part is brought into contact with the part to be measured where a gap has occurred, the air flowing into the gap will be converged and most of it will be absorbed by the wind speed detector and the wind speed detector. It is introduced only through the air passage. The presence of the gap is detected by the i-pattern wind speed detector detecting the wind speed due to the flow of the leaked air.

[Example J The present invention will be described below based on illustrated embodiments.

FIG. 1 is a diagram showing the basic configuration of the air leakage device of the present invention. In this figure, 1 is a wind collecting part whose periphery is formed in a shape that follows the surface of the measurement target part, 2 is an air passage connected to this wind collecting part l, and 3 is a slight wind velocity connected to the air passage 2. It is a detector.

Figures 2 and 3 show condensate'? +RA and low pressure turbine B
Connect the connection part of a! 11 shows a specific example of the wind collecting section 1 in the case where it is a constant target section. As shown in FIG. 2, a rubber gasket C having a thickness of, for example, about 200 mm may be interposed between each flange AI, 87 of the condenser A and the low pressure turbine B. In such a case, there will be a large gap between the flanges AI and B1. The wind collection section I shown in FIGS. 2 and 3 has a cup-shaped wind collection body 11 made of magnet I/rubber, and a wind collection body 11 made of magnet I/rubber in order to correspond to the shape of the measurement target part. A sponge filling material 1 is loaded between the flanges AI and B1 at a position corresponding to the opening periphery 11a.
It is composed of 2. As shown in FIG. B1 is provided with an opening having a diameter large enough to abut on both flanges, and the area around the opening Ha is 1. It is formed in a curved shape so as to follow the curved surface of the outer peripheral surface of B1. On the other hand, the filling material 12 is arranged around both flanges AI, around the opening 11a of the collection book body 11,
81, and when no external compressive force is applied in the pushed state, connect the loading site, that is, the lower end of flange A1 and the upper end of flange B1, as shown by the dashed line in Fig. 2. It consists of just enough sponge material to protrude from the wire. This filling material 12 is
The collection book main body 1 is attached using adhesive or a separate mounting member.
1 may be installed in advance, or it may be made as a separate member from the main body 11 of the main body 11 and pushed into the loading area before applying the main body 11 of the main body 11 to be measured. There may be.

The air passage 2 is connected to the bottom of the wind collection main body 11 and communicates with the inside of the wind collection main body 11, and is constructed using a resin pipe or port.

The slight wind speed detector 3 is configured as shown in FIG. 3, for example. In other words, in the case shown in FIG. 3, when the resistance value of the wind velocity measuring resistor 31a constituting the Poyton Stone Bridge 31 changes as it is cooled by the air sent to the measuring object through the air passage 2, the change occurs. A signal corresponding to the voltage is outputted via the differential amplifier 32, and the wind speed can be determined by the pointer 33 that swings in response to the signal, and the signal voltage compared with the reference voltage is When the voltage is higher than this reference voltage, this can be displayed on the display section 35.

However, 31b is a comparison resistor constituting the Poytonstone bridge 31, 3IC is a fixed resistor, 31d is an adjustment variable resistor, and 31e is a power supply.

Using the air leak detection device constructed as described above,
When the wind collecting part 1 is applied to the flange 8l and Bl joint part of the condenser A and the low pressure turbine B, which are the parts to be measured, the wind collecting body 11 made of the magnetic screw 1 to the rubber will be attached to the flange A1.
．． Adsorbed to B1, the filling material 12 is attached to the flange AI, 8
1. It is loaded into the space formed by the rubber gasket C and the collection book main body 11. Therefore, if a gap is created in the area where the air collecting section 1 is applied, the converged air passing through the small wind speed detector 3 and the air passage 2 will leak into the inside of the measurement target section through the gap. In this way, what passes through the small wind speed detector 3 is the converged air flow, and only the air flow leaking into the gap, so the detection accuracy may be affected by the atmospheric flow caused by other factors such as rising air currents. is unaffected, and the existence of the gap is therefore reliably confirmed.

It should be noted that the present invention is of course not limited to the above-mentioned embodiments, and for example, the design of the wind collecting section can be changed in various ways depending on the shape of the part to be measured. That is, in addition to the above-mentioned condenser, the turbine equipment has a!
11. The air collector has many negative pressure parts that serve as constant target parts, and the air collection part has a small wind speed detector and a converged air introduced through the air passage in accordance with the shape of such negative pressure parts. Any material may be used as long as it is formed so as to leak through the gap. Therefore, multiple wind collectors with different shapes are manufactured,
These can also be attached to and detached from the air passage as attachments, and in this way it is possible to more quickly detect air leakage from various measurement target parts.

[Effects of the Invention] As is clear from the above description, the air leakage detection device in the negative pressure section according to the present invention can detect the converged air flow flowing into the gap. Since the flow of air is not affected by atmospheric flow caused by other factors, it is possible to reliably detect the inflow of air into a gap, and therefore the presence of a gap can be detected extremely reliably. be effective.

[Brief explanation of the drawing]

Fig. 1 is a diagram showing the basics of the present invention +1, Fig. 2 is a partially cutaway side view of the main part showing how to use the wind collecting section 73 of the embodiment,
FIG. 3 is a partial plan view, and FIG. 4 is a block circuit diagram of the small wind speed detector.

Claims (1)

[Claims] (1) A wind collecting part having a cup-shaped wind collecting part main body whose opening periphery can be substantially aligned with the surface of the measurement target part, an air passage connected to the air collecting part main body, and an air passage connected to the measurement target part through this passage. Air leakage into a negative pressure part, characterized in that it is equipped with a slight wind speed detector that detects air leaking from the part into the negative pressure side of the part and generates a detection signal when the wind speed of this air is equal to or higher than a predetermined value. Detection device.