JPH0247520A - Washing device of electromagnetic flowmeter - Google Patents

Abstract

PURPOSE:To prevent the sticking of sludge by disposing an ultrasonic sludge concentration meter on the upstream side of an electromagnetic flowmeter and by providing a measured sample returning port thereof near an inlet of the electromagnetic flowmeter. CONSTITUTION:By making a current flow through a coil of a detector 3 in a sludge water piping 1, a voltage proportional to the flow rate of the sludge water is obtained, and it is amplified to be a flow rate signal by an electromagnetic flowmeter 2. Part of the sludge water is taken out of a sample takeout- return port 5, a pressure gas is supplied to remove bubbles in sludge, and the concentration of the sludge is detected by a detector 7. A sample taken in the detector 7 is returned into the sludge water piping 1 from the sample takeout-return port 5. Since a high gas pressure is applied to the detector 7 on the occasion, a strong turbulent flow occurs in the sludge water in the piping 1. The sludge sticking on the inside of the detector 3 of the electromagnetic flowmeter 2 can be removed thereby.

Description

DETAILED DESCRIPTION OF THE INVENTION [Object of the Invention] (Industrial Application Field) The present invention relates to a cleaning device for an electromagnetic flowmeter as a flow rate measuring means in sewage piping.

(Prior art) Electromagnetic flowmeters are generally used to detect the flow rate of wastewater flowing into wastewater pipes such as factory wastewater and sewage. The flow rate of sewage is detected by connecting a detector, passing a current through a coil wrapped around the detector, creating a magnetic field inside the pipe, and detecting the voltage generated at the electrodes when sewage crosses this magnetic field. It is configured.

(Problem to be Solved by the Invention) However, in such conventional electromagnetic flowmeters, when waste water passes through the detector, it adheres to the inner surface of the detector, and the detection sensitivity decreases over time, causing the flow rate indication There is a problem that the detection capacity decreases, and in order to restore the detection capacity by cleaning the inner surface of the detector due to the decrease in detection capacity, it is necessary to remove the detector from the sewage pipe and clean it. There was a problem in that it was time consuming and costly.

This invention was made in view of these conventional problems, and uses the unique operation of an ultrasonic sludge concentration meter that is thrown alongside an electromagnetic flowmeter into a wastewater pipe to detect an electromagnetic flowmeter. An electromagnetic flowmeter cleaning device that prevents dirt from adhering to the inside of the flowmeter, prevents a decline in the detection ability of the flowmeter, and reduces cleaning costs by lengthening the cycle for cleaning dirt. The purpose is to provide

[Structure of the Invention] (Means for Solving the Problems) The electromagnetic flowmeter cleaning device of the present invention includes an ultrasonic sludge concentration meter that uses pressurized gas in close proximity to the upstream side of the electromagnetic flowmeter for wastewater piping. The measured sample return port of the ultrasonic sludge ammeter is provided near the inlet of the electromagnetic flowmeter.

(Function) In the electromagnetic flowmeter cleaning device of the present invention, an ultrasonic sludge concentration meter using pressurized gas is disposed close to the upstream side of the electromagnetic flowmeter for wastewater piping, and the ultrasonic sludge concentration meter By providing the measured sample return port near the inlet of the electromagnetic flowmeter, the electromagnetic flowmeter can be operated using the turbulent flow caused by the pressurized gas of the sample on the concentration meter side, which is returned from the measured sample return port into the wastewater piping. Clean the inside surface of the detector to keep the measuring ability of the electromagnetic flowmeter high over a long period of time.

(Example) Hereinafter, embodiments of the present invention will be explained in detail based on the drawings.

FIG. 1 shows an embodiment of the present invention, in which sewage pipe 1
A detector 3 of an N magnetic current concavity meter 2 is connected to the middle of the line.

And on the upstream side of the detector 3 of this electromagnetic flowmeter 2,
A defoaming type ultrasonic sludge concentration meter 4 is provided for the sewage pipe 1, and a sample take-out/return port 5 for the defoaming type sludge concentration meter 4 for the sewage pipe 1 is the inlet of the electromagnetic flow meter detector 3. It is located close to the side.

A valve 6 and a concentration detection section 7 are provided for the sample takeout/return port 5 of the defoaming sludge concentration meter 4.
Pressurized gas is supplied to the concentration detection section 7.

The electromagnetic flowmeter 2 described above creates a magnetic field in the pipe 1 by passing a current through the coil of the detector 3 against the wastewater flowing inside the pipe 1, and generates a voltage proportional to the flow rate of the wastewater flowing inside the pipe 1. It is taken out from the detector 3, amplified in the electromagnetic flowmeter 2, and taken out as a flow rate signal.

In addition, in the defoaming type ultrasonic sludge concentration meter 4, a part of the sewage from the sewage pipe 1 is transferred from the sample takeout/return port 5 to the valve 6.
The sludge is opened and taken out to the detection section 7, where pressurized gas is supplied to remove air bubbles in the sludge, and the amount of sludge is measured to detect the concentration in the sewage, which is output from the densitometer 4.

Then, the sample taken into the detection section 7 is returned to the wastewater pipe 1 through the sample takeout/return port 5 by opening the valve 6 again. At this time, the pressure supplied to the detection section 7 is The gas increases the pressure of the sample, and the sample is returned to the sewage pipe 1 from the sample take-out/return port 5 under high pressure. It flows into the detector 3 of No. 2.

Therefore, any dirt that has adhered to the inner surface of the detector 3 of the electromagnetic flowmeter 2 will be removed into the waste water by this turbulent flow, reducing the amount of dirt adhering to the inner surface of the detector 3, which will last for a long time. This makes it possible to detect the flow rate with stable accuracy.

FIG. 2 shows an embodiment of the present invention, in which when measuring the sludge concentration of sewage in the sewage pipe 1 using the defoaming type ultrasonic sludge concentration meter 4, the sample after measurement is taken from the sample takeout/return port 5. When the water is returned to the sewage pipe 1 at high pressure, a turbulent flow will occur in the sewage pipe 1, but if the sewage flow rate is measured at the electromagnetic flow meter detector 3 while this turbulent flow is flowing, For example, the flow rate measurement value fluctuates greatly, making it impossible to accurately measure the flow rate.

Therefore, in the embodiment shown in FIG. 2, the sludge concentration of the sewage in the sewage pipe 1 is measured by the sludge concentration meter 4, and the sewage flow rate is not measured by the electromagnetic flow meter 2 while the sludge concentration is being discharged. In order to hold the flow rate detection value at the flow rate, a cleaning timing signal 8 is outputted from the sludge concentration meter 4 to the electromagnetic flow meter 2.

In this way, it is possible to prevent the detected value of flow m on the electromagnetic flow meter 2 from being disturbed due to the turbulent flow that occurs when the sludge concentration meter 4 is operated and the sample is returned to the sewage pipe 1 at high pressure, and accurate flow rate detection output can be achieved. You will be able to obtain

In the embodiment shown in FIG. 2, parts designated by the same reference numerals as in the embodiment shown in FIG. 1 have the same configuration.

FIG. 3 shows still another embodiment of the present invention, in which an electromagnetic flowmeter detector 3 is connected to the middle of the sewage pipe 1, and
A defoaming type ultrasonic sludge concentration meter 4 is installed close to the upstream side of this detector 3, and a timing manual/automatic changeover switch 9 is installed.
By using this timing manual/automatic changeover switch 9, the pressurized gas tank 1 is released from the pressurized gas outlet 11 provided near the sample takeout/return port 5 of the sewage pipe 1 via the valve 10.
This is an embodiment in which pressurized gas No. 2 is ejected.

In this embodiment, the timing manual/automatic changeover switch 9
If it is switched to the automatic side, the defoaming type ultrasonic sludge concentration meter 4 will operate, and after measuring the sludge concentration, the valve 6.10 will open and the pressurized sludge sample in the detection section 7 will pass through the sample take-out/return port. 5
The pressurized gas is discharged from the pressurized gas outlet 11 to generate a turbulent flow of sewage at the electromagnetic flowmeter detector 3, and the inner surface of the detector 3 is automatically cleaned. can be done.

Also, if the timing manual/automatic changeover switch 9 is switched to the manual side, the valve 10 opens and the pressurized gas tank 12
The pressurized gas flows from the sewage pipe 1 through the pressurized gas outlet 11
It is possible to forcefully generate a large turbulent flow of waste water on the inlet side of the electromagnetic flowmeter detector 3, and the dirt on the inner surface of the detector 3 can be effectively cleaned. .

In the embodiment shown in FIG. 3, the sludge concentration is measured by the sludge concentration meter 4, and the sample after the measurement is returned to the sewage pipe 1 through the sample take-out/return port 5. A cleaning timing signal 8 is provided from the sludge concentration meter 4 to the electromagnetic flowmeter 2 to stop the flow rate detection operation of the electromagnetic flowmeter 2 and hold the flow rate measurement value before the occurrence of turbulence.

In addition, the timing manual/automatic changeover switch 9 releases pressurized gas from the pressurized gas tank 12 directly into the waste water pipe 1 through the pressurized gas outlet 11 to generate turbulent flow, which can be used to detect the electromagnetic flowmeter 2. 3, the cleaning timing signal 8 is applied from the timing manual/automatic changeover switch 9 to the electromagnetic flowmeter 2 to hold the flow rate measurement value before cleaning, and the flow rate measurement is not performed during cleaning. Don't do it.

[Effect of the Invention 1 As described above, according to the present invention, the sample take-out/return port of the ultrasonic sludge concentration meter is provided on the upstream side of the sewage pipe close to the electromagnetic flowmeter, and the sample is returned from the sample take-out/return port. Since the turbulent flow of sewage is generated on the inlet side of the detector by the sample being collected, it is possible to clean the inside surface of the electromagnetic flowmeter's detector when measuring sludge concentration in sewage using a sludge concentration meter. The inner surface of the electromagnetic flowmeter detector can always be kept free of dirt, allowing accurate flow rate detection over a long period of time.

In addition, since it is possible to reduce the amount of dirt adhering to the inside of the electromagnetic flowmeter's detector over a long period of time, it is possible to lengthen the cleaning cycle of the electromagnetic flowmeter, reducing cleaning costs and labor. It can be significantly reduced.

[Brief explanation of the drawing]

FIG. 1 is a system diagram of one embodiment of the present invention, FIG. 2 is a system diagram of a third embodiment of the invention, and FIG. 3 is a system diagram of yet another embodiment of the invention. 1...Sewage piping 2...Electromagnetic flow meter 3...Detector 4...Defoaming sludge concentration meter 5...Sample extraction/return port 6...Valve 7...Detection part 8 ...Cleaning timing signal

Claims (1)

[Claims] An ultrasonic sludge concentration meter that uses pressurized gas is installed close to the upstream side of the electromagnetic flowmeter for the wastewater piping, and the measured sample return port of the ultrasonic sludge concentration meter is connected to the electromagnetic flowmeter. An electromagnetic flow meter cleaning device installed near the entrance.