JPH09196716A - Simple flow rate measuring apparatus - Google Patents

Abstract

PROBLEM TO BE SOLVED: To obtain a simple flow rate measuring apparatus by which a flow rate flowing down at the inside of a valve can be measured whenever the valve is opened by a method wherein a storage part is installed and the relationship between the opening of the valve, a flow rate according to a differential pressure and a vibration is stored. SOLUTION: A vibration detecting rod 1 is attached firmly to a measuring instrument body 2 by a screw coupling operation. A piezoelectric element which converts a mechanical vibration into an electric signal is arranged at the inside of the vibration detecting rod 1, and it is connected to an amplifier at the inside of the body 2. The relationship between the opening of a valve, a flow rate according to a differential pressure and a vibration regarding an object to be measured is measured in advance so as to be stored in a storage card 3. Regarding the relationship between the opening of the valve, the vibration and the flow rate, a nearly constant relationship is obtained when a valve is provided with a specific structure. Normally, various valves such as a plug valve, a butterfly valve, a pressure reducing valve and the like are used in various fluid pipes. However, when the vibration detecting rod 1 is just pressed to the valves, an approximate flow rate flowing down in the valves can be converted and measured on the basis of the relationship, between the vibration and the flow rate, which is measured in advance so as to be stored.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention detects the amount of fluid flowing down a valve used for controlling the flow of various fluids in various factories and production plants by detecting the vibration generated in the valve, The present invention relates to a simple flow rate measuring device that converts from vibration values.

[0002]

2. Description of the Related Art Conventionally, various types of flowmeters such as an orifice type, a volume type, an ultrasonic type, and a Karman vortex type have been used according to the application, and a relatively accurate flow rate value can be obtained. It is an effective flow measurement device when required.

A method for measuring the flow rate from the vibration generated in the valve is disclosed in Japanese Patent Publication No. 3888/1993. This is because when a mixed fluid of gas and liquid flows in the valve, the relationship between the vibration and the flow rate when each fluid flows is measured and stored in advance, and the valve is calculated from the actually measured vibration value and the above relationship. To convert the flow rate of.

[0004]

In the case of the Karman vortex type flowmeter among the above-mentioned prior arts, a single flowmeter member must be installed only for the purpose of measuring the flow rate, and the installation work is difficult. There was a costly problem. In particular, there is a problem that the cost ratio increases at a place where it is not necessary to constantly measure the flow rate.

Further, the conventional method for measuring the flow rate from the vibration generated in the valve has a problem that the flow rate cannot be measured for each opening of the valve.

Therefore, it is an object of the present invention to measure the flow rate flowing down the inside of a valve already attached to a pipe for each valve opening, without the need to newly install a single flow meter. It is to provide a simple flow rate measuring device that can be used.

[0007]

[Means for Solving the Problems] Means for solving the above-mentioned problems are to detect the vibration generated inside the valve from the outer surface of the valve through which various fluids flow down, and to detect the valve from the detected vibration value. In the case of converting the flow rate flowing down the inside, a storage unit for storing beforehand the relationship between the flow rate and vibration according to the opening degree and differential pressure of the valve to be measured is provided, and the vibration actually measured and the above memory are stored. Based on the relationship between the vibration and the flow rate, the approximate flow rate flowing down the valve having a predetermined opening is converted and displayed.

[0008]

BEST MODE FOR CARRYING OUT THE INVENTION A flow rate according to a valve opening and a differential pressure,
By storing the relationship of vibration, it is possible to convert the measured flow value into a rough flow rate corresponding to the predetermined opening degree of the valve for measurement.

[0009]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Referring to FIG. 1, a vibration detecting rod 1 for contacting a valve to detect vibration, a measuring device main body 2, and a memory card as a memory unit for storing a previously measured relationship between vibration and flow rate. Dod 3 constitutes a simple flow rate measuring device.

The vibration detecting rod 1 is made of a tapered metal and has its upper end pressed against the outer surface of the flow rate measuring object (not shown) to detect vibrations. Attach to. Inside the vibration detection rod 1, a piezoelectric element for converting mechanical vibration into an electric signal is arranged and connected to an amplifier (not shown) in the measuring device main body 2.

In addition to the amplifier, a filter is provided in the measuring device main body 2.
In addition to the built-in reading section of the memory card 3, the comparing section, the calculating section, etc., the display section 4 and the changeover switch 5 for various modes, the power switch 6 or the numeric keypad 7 are provided.

In the memory card 3, the relationship between the flow rate and the vibration according to the opening degree and the differential pressure of the valve to be measured is measured and stored in advance. As for the relationship between the valve opening degree, the vibration, and the differential pressure, for example, as shown in FIG. 2, an almost constant relationship can be obtained if the valve has a specific structure. In FIG. 2, the vibration value is plotted on the vertical axis 10 and the valve opening is plotted on the horizontal axis 11, and the case where the differential pressure before and after the valve is 5 km is shown by the curve 12, and the differential pressure of 3 km is the curve 13 as well.
The differential pressure of 1 km is indicated by the curve 14, and the flow rate value is associated with this relationship and stored in the storage card 3.

Various structures of valves are used to control fluids in various factories. Generally, those used to control the flow rate are plug valves and cage valves as automatic control valves, but also butterfly valves, ball valves, ball valves, self-powered valves that can be fully closed. As the adjusting valve, a versatile one such as a pressure reducing valve, a primary pressure adjusting valve or a differential pressure adjusting valve is used. The memory card 3 stores the relationship between the vibration and the flow rate for each type of these valves, or a specific group.
You can memorize the relationship for each group.

Further, since the flow rate flowing down the valve changes depending on the kind such as the specific gravity and viscosity of the fluid, or the temperature and the ratio of the mixture, the relationship between the vibration and the flow rate including these conditions is stored. If so, the flow rate can be measured more accurately.

Usually, the above various valves are attached to various fluid pipes in order to adjust the flow rate, temperature and pressure.
The simple flow rate measuring device of the present embodiment converts the approximate flow rate flowing down the valve from the relationship between the vibration and the flow rate, which is measured and stored in advance, only by pressing the vibration detection rod 1 against these valves to measure. can do.

[0016]

According to the present invention, it is possible to detect the vibrations of various valves that are already installed without separately installing a single flow meter, and to open the previously stored valve values and the vibration values. The flow rate flowing down can be simply measured from the relationship between the flow rate and the vibration depending on the degree and the differential pressure.

[Brief description of drawings]

FIG. 1 is a configuration diagram showing an embodiment of a simple flow rate measuring device of the present invention.

FIG. 2 is a diagram showing a relationship between valve opening and vibration, which is stored in advance in the simple flow rate measuring device of the present invention.

[Explanation of symbols]

 1 Vibration detection rod 2 Measuring instrument main body 3 Memory card 4 Display

Claims (1)

[Claims] 1. A method of detecting the vibration generated in the valve from the outer surface of the valve through which various fluids flow down, and converting the flow rate flowing down in the valve from the detected vibration value to open the valve to be measured. A storage unit that stores in advance the relationship between the flow rate and vibration according to the degree and the differential pressure is provided, and the valve having a predetermined opening is flowed down based on the actually measured vibration and the stored relationship between the vibration and the flow rate. A simple flow rate measuring device characterized by converting and displaying an approximate flow rate.