JPS6264914A - Apparatus for measuring flow - Google Patents

Abstract

PURPOSE:To provide the titled apparatus having a simple structure, reduced in pressure loss and capable of always keeping measuring function well, by providing a bent pipe, of which the open end is directed to the upstream side of flow, to the inlet part of a flow dividing pipe and a bent pipe, of which the open end is directed to the downstream side, to the outlet part of said flow dividing pipe. CONSTITUTION:The bent pipes 12, 13 connected to the inlet part and outlet part sides of a flow dividing pipe 20 are arranged so that the open ends 12a, 13a thereof are respectively directed to the upstream and downstream sides so as to provide a predetermined interval therebetween and, not only the pressure difference between total pressure and static pressure but also larger pressure difference due to the vortex stream generated in the vicinity of the open end 13a of the bent pipe 13 are generated between the inlet part and outlet part of the flow dividing pipe 20. A part of the fluid in a main pipe 11 flows in the flow dividing pipe 20 from the bent pipe 12 through an opening/closing valve 14a and, after a flowmeter 21 was operated, a stream passing through an opening/closing valve 14b and the bent pipe 13 to return to the main pipe 11 is generated. Because the flow in the flow dividing pipe 20 is correlative to that in the main pipe 11, by measuring the flow in the flow dividing pipe 20 by the flowmeter 21, the flow in the main pipe 11 can be measured.

Description

[Detailed Description of the Invention] [Technical Field of the Invention] The present invention relates to a method for measuring the flow R of a fluid flowing in a pipe.
The present invention relates to a measuring device, and particularly to a branch type flow measuring device that measures fluid flow by providing a branch pipe in the middle of a pipe and measuring the flow rate flowing through the branch pipe.

(Technical Background of the Invention and Problems Thereof) A split flow type flow a measuring device is known as a device for measuring the flow rate of fluid flowing in a main pipe. This split flow measuring device d connects the inlet and outlet of the branch pipe line before and after the throttle mechanism such as an orifice provided in the main pipe, and measures the split flow caused by the differential pressure before and after the throttle mechanism such as the orifice. The flow rate of fluid flowing in the main pipe is measured by the flow rate i1 disposed in the branch pipe.

This branch type flow measurement device can measure the flow rate by measuring a relatively small flow rate of fluid flowing in the branch pipe, so even if the flow IB flowing in the main pipe is large, it can be used even if the flow is small. Using a flowmeter to make a measuring device, miniaturize a flow rate measuring device, 1iIli! There is a report that it is possible to reduce the amount by 8.

However, in the conventional split flow measuring device,
- Since a restriction such as an orifice was installed in the pipe, there was a large pressure loss, and when a large flow rate was flowing, there was no place for people to go.
This resulted in energy loss. In addition, if the orifice etc. becomes worn or damaged, the -1 pipe mouth body must be disassembled and the orifice etc. must be replaced or cleaned. Stop the flow of fluid within
If it was my turn, it would be ζ1 et/2. It is important to maintain the functionality of the flow rate measuring device at all times, since it requires a great deal of effort and expense to frequently replace or clean the orifices, etc. that generate the differential pressure. was actually difficult.

(Objective of the Invention) The present invention has been made with these points in mind. The object of the present invention is to provide a separate flow l-measuring device.

(Summary of the Invention) The present invention is a branch type flow rate measuring device that measures the flow portion of a fluid flowing in a pipe, and includes an i! ! ! Connect a branch pipe with a number 1 to the flow part in the middle of the main pipe through which the measurement fluid flows,
A bent pipe with its front end facing the upstream side of the flow direction one nozzle at the inlet of the branch pipe, and a bent pipe with its open end facing the downstream side of the flow at the outlet of the branch pipe were inserted into the main pipe, respectively. It is made up of connected items.

[Embodiments of the invention]

Embodiments of the present invention will be described below with reference to the drawings.

FIG. 1 is a side view, partially in cross section, of an example of a flow rate measuring device according to the present invention. In the figure, η11 is a main pipe through which a fluid to be measured, such as water or seawater, flows. The fluid flows inside this main pipe 11 from the upstream side (left side in Figure 1) to the downstream side (the first
(right side of the figure) in the direction of the arrow. In one pipe 11, two bent pipes 12 and 13 are arranged at a predetermined interval.

In this embodiment, a long elbow having a bending angle of 90° is used as the bent pipe 12.13, and the bent pipe 12 disposed on the flow side has its open end 12;1 facing the upstream side. The bent pipe 13 disposed on the downstream side has its opening) W
138 toward the downstream side, and the bent pipes 12.
13 square end portion 12b.

13b is extended outward from the tube 11.

There are gaps e in the other parts 12b and 13b of the bent pipe 12.13.
The opening/closing button tl'lEl, 14b is connected, and this 1) is closed i? 14a and 14b, each end of the branch pipe 20 is connected using pipe joints 15f1 and 15b. In this embodiment, ball valves are used as the on-off valves 14a and 14b, and unions are used as the pipe joints J5a and 15b.

A flow meter 21 is provided in the middle of the divided stream 20 31
In this embodiment, a flowmeter 21 is used as the flow meter 21, but other flowmeters such as an area flow 181 can be used for various flow sections.

FIG. 2 is a scale sectional view of an example of a cleaning tool used in the flow measuring device according to this embodiment having such a configuration. In the figure, numeral 31 is a hollow cylindrical pipe,
Inside this vibe 31, there is a t screwed onto the upper end of the pipe 31.
- An elongated shaft 32 is inserted through the shaft 34 so as to be movable forward and backward. Tip portion 32a of seat lift 32
is made of a flexible member, and a brush member 33 is arranged around the outer periphery of the brush member 33. The lower end of the vibrator 31 is open, and the buninoshi part shrine 33 can be advanced freely, and a union foot 35 is attached to the outer periphery of the lower end. Reference numeral 32b denotes a handle attached to the end of the shaft 32.

Next, the operation of this embodiment based on this configuration will be explained.

The flow part of the fluid flowing inside the main pipe 11 is measured by the on-off valve 14a.
, 14b and create a shunt in the shunt pipe 20. The bent pipe 12°13 connected to the artificial part side and the outlet part side of the branch pipe 20 has an opening E12a,
13a are respectively arranged toward the upstream side J5 and the upstream side, and are arranged at predetermined intervals, so that
There is a pressure difference between the inlet and the outlet of the branch pipe 20 due to the total pressure and static pressure, as well as the open end 13 of the bent pipe 13 on the downstream side.
A larger pressure difference is generated due to the vortex generated near a, and a part of the fluid in the main pipe 11 is transferred from the bent pipe 12 to the on-off valve 1.
After flowing into the branch pipe 20 through 4a and operating the flow meter 21, it flows through the on-off valve 14b and the bend ¥113 to the main pipe 11.
A flow returns inward. Since the flow rate in this branch pipe 20 has a correlation with the flow peak in the main pipe 11, the flow rate in the main pipe 11 can be measured by measuring the flow peak in the branch pipe 20 with the flowmeter 21.
can be measured.

In addition, when cleaning the inside of the branch pipe 20, first clean the on-off valve 1.
4a and 14b to stop the branching, pipe joint 15
The branch pipe 20 is separated from the on-off valves 14a and 14b by a and 15b. The separated flow branch pipe 20 can be transported to another location together with the flow meter 21 and cleaned by an appropriate method. In addition, the on-off valves 14a and 14b are provided with a union nut.
1" 35 to connect and fix the cleaning tools 30 shown in FIG.
14b into the bent tube 12.13. Since the brush member 33 is attached to the flexible tip 32a, it can easily enter the bent pipe 12.13.
Dirt inside the bent pipes 12 and 13 can be removed. While cleaning the inside of the bend 1g12.13 and the on-off valves 1ia and 14b using this cleaning tool 30, - inside the main pipe 11;

The fluid flow may not stop. After the cleaning work is completed, Ruto
Open m valves 14a, 14blEnL;, After removing cleaning tool 30, open/close valve 14a of diverter pipe 20;

14b, the series of cleaning steps is completed.

In this way, according to this embodiment, it is possible to configure a branch type flow rate measuring device without providing a throttling mechanism such as an orifice in the main pipe 11, so compared to the conventional structure in which a throttling mechanism such as an orifice is provided. Pressure loss can be significantly reduced. Furthermore, even if the main pipe 11 has a large diameter, the branch pipe 2° can be composed of a small diameter pipe, and
Since a large flow can be measured by measuring a relatively small flow rate, the flow meter 21 can be downsized, and the flow a measuring device can be downsized and the price can be reduced.

Furthermore, since the branch pipe 20 is removable, the branch pipe 20 is removable.
0 and the flow meter 21 are easy to remove and clean, and
By using the cleaning tool 30, the inlet and outlet sides of the branch pipe 20 can be easily cleaned without stopping the flow of fluid in the main pipe 11. Thereby, the function of the flow rate measuring device can always be maintained well, and the reliability of the device can be improved.

In the description of this embodiment, an example was shown in which a long elbow with a 90" bending angle was used as the bent pipe 12.13 inserted into the main pipe 11, but this bending angle is not necessarily limited to 90°. In addition, although an example is shown in which the open ends 12a, 13a of the bent pipes 12.13 are arranged on the central axis of the main pipe 11, depending on the diameter of the main pipe 11 and the flow rate of the fluid, the open ends 12a, 13a, 13a is the main control 11
It may be arranged at a position eccentric from the center 44IQ.

(Effects of the Invention) As described above, according to the present invention, it is possible to obtain a split-flow type 1ffi measuring device that has a small pressure loss and can save energy. In addition, the flow rate measuring device according to the present invention not only allows for miniaturization of the flow rate measuring device, but also has a simple structure and is easy to clean, which reduces the effort and expense required to always maintain good measurement functions. You can save a lot.

This invention is big 2/! When used as a flow rate measuring device, particularly excellent effects can be achieved.

[Brief explanation of drawings]

FIG. 1 is a side view showing an embodiment of the flow rate measuring device according to the present invention, but includes a partial cross section, and FIG. 2 is a sectional view showing an example of a cleaning tool used in the flow rate measuring device according to the present invention. 11... Main pipe, 12.13... Bent pipe, 12a. 13a... Frontage end, 14a, 14b... On-off valve, 1
5a, 15b... Pipe joint, 20... Branch pipe, 21.
...Flow meter, 30...Seiwa shellfish.

Claims (1)

[Claims] 1. A branch pipe with a flow meter installed in the middle is connected to the main pipe through which the fluid to be measured flows, and a bent pipe with the open end facing upstream of the flow is connected to the inlet of the branch pipe. , a flow rate measuring device comprising bent pipes each inserted into the main pipe and connected to the outlet portion of the branch pipe with the open end facing downstream of the flow. 2. The flow rate measuring device according to claim 1, wherein the inlet and outlet of the branch pipe are respectively openable and closable. 3. The flow measuring device according to claim 2, wherein the branch pipe is detachably connected to the main pipe. 4. The flow measuring device according to claim 2, wherein the inlet and outlet of the branch pipe are each connected to the main pipe via an on-off valve.