JPH07248241A - Vibration type measuring apparatus - Google Patents

Abstract

PURPOSE:To facilitate the cleaning of the inside of a sensor tube by providing a connection part at an inflow side end part and an outflow side end part of a pipeline sticking outside a casing. CONSTITUTION:A mass flowmeter 1 is made up of a casing 2, a pair of pipelines 3 and 4 and inflow side and outflow side manifolds 5 and 6 formed at the both ends of the pipelines 3 and 4. Flanges 3a, 3b, 4a and 4b are provided at an end part sticking out of inflow side and outflow side end faces 2a and 2b of the casing 2 as inflow side and outflow side connection parts. Therefore, the casing 2 can be removed from a piping system line with ease simply by separating the inflow side end part 2a and the outflow side end part 2b from the inflow side manifold 5 and the inflow side manifold 6. Moreover, the shape of an upright tube of a pair of upright tube-shaped sensor tubes housed in the casing 2 enables the removal of a fluid to be measured left in the pipelines in a short time.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a vibration type measuring device,
In particular, the present invention relates to a vibration type measuring device for measuring the mass flow rate or density by vibrating the inside of a straight tubular sensor tube through which a fluid to be measured flows.

[0002]

2. Description of the Related Art As a vibration type measuring device for measuring a physical quantity of a fluid by vibrating a pipe line to which the fluid is supplied, there is, for example, a Coriolis mass flow meter or a vibrating density meter.

When measuring the flow rate, it is desirable that the flow rate of the fluid to be measured be represented by a mass that is not affected by the type of fluid, physical properties (density, viscosity, etc.) and process conditions (temperature, pressure).

Therefore, various mass flowmeters for measuring the mass flow rate of the fluid to be measured are being developed, and one of them is Coriolis force generated when a fluid is flown into an oscillating straight tubular sensor tube. There is a Coriolis mass flow meter that directly measures the mass flow rate by utilizing it.

An example of this type of conventional mass flowmeter is the flowmeter disclosed in Japanese Patent Application Laid-Open No. 63-30721. In the mass flowmeter of this publication, in order to reduce the pressure loss when the fluid to be measured passes, a straight tubular sensor tube is vibrated in a radial direction by an exciter (consisting of a drive coil and a magnet). Then, the displacement of the straight tubular sensor tube due to the Coriolis force proportional to the flow rate is detected by the vibration sensor (consisting of the sensor coil and the magnet).

Further, in the case of the vibration type density meter, it has the same structure as the Coriolis type mass flow meter, and the density of the fluid is measured from the natural frequency of the straight tubular sensor tube.

[0007]

In the above vibration type measuring device, the mass flow rate or density is measured while flowing the fluid to be measured in the straight tubular sensor tube vibrating as described above.
It is possible to measure not only liquids and gases but also viscous fluids in a slurry state. However, when switching to measure different types of fluids to be measured depending on time, such as in a food production line, or moving to each site like a construction site to measure cement etc., the work at that site When finished, it may be moved to the next site.

As described above, when the type of the fluid to be measured is changed or the device itself needs to be moved, the fluid to be measured is mixed with other fluid to be measured or the fluid to be measured solidifies on the inner wall of the pipe. Therefore, it is necessary to remove the measured fluid remaining in the pipe.

However, in the conventional vibration type measuring device, if the straight tubular sensor tube is bent, it is difficult to clean the inside of the straight tubular sensor tube, and even in the case of the straight straight tubular sensor tube, the device should be removed from the pipe. Without it, it was difficult to wash. Therefore, for example, in the case of a food processing line, etc., it is important to make a request from the viewpoint of hygiene, but if the previous food remains every time the type of food to be fed is changed, the food to be fed next time Not hygienic mixed with.

Moreover, when cleaning the inside of the straight tubular sensor tube, the worker removes the device from the pipe, and then takes out the straight tubular sensor tube from the casing to perform the cleaning work. Therefore, conventionally, there is a problem that the cleaning work requires a considerable amount of time and labor.

Further, in the apparatus for bending the straight sensor tube, not only the pressure loss when the fluid to be measured flows becomes large, but also a lot of labor is required to maintain the processing accuracy of the tube, resulting in a manufacturing cost. Will also be expensive.

Therefore, an object of the present invention is to provide a vibration type measuring device which solves the above problems.

[0013]

According to the present invention, there is provided a casing having a closed casing, one end of which is opened as an inflow side connecting portion from the inflow side end portion of the casing to the outside, and the other end of which extends through the casing. A pair of straight tubular sensor tubes that are open to the outside from the outflow side end portions as outflow side connecting portions, a vibrator provided in the casing for vibrating the pair of straight tubular sensor tubes, and the pair of straight tubular A pair of vibration sensors for detecting displacements of the straight tubular sensor tube on the upstream side and the downstream side due to the vibration of the sensor tube, an inflow side manifold connected to the inflow side connection portion, and an outflow connected to the outflow side connection portion. And a side manifold.

[0014]

[Operation] Since the inflow side and the outflow side connection parts are provided at the inflow side end part and the outflow side end part of the pair of pipelines protruding to the outside of the casing, the inflow side end part and the outflow side end part are connected to the inflow side end part. The casing that houses the pair of straight tubular sensor tubes can be removed from the piping system by simply separating it from the manifold and the outflow side manifold, and the inside of the pair of straight tubular sensor tubes housed in the casing can be easily washed. .

[0015]

1 to 3 show a Coriolis mass flowmeter as an embodiment of a vibration measuring apparatus according to the present invention.

As the vibration type measuring device, there are a Coriolis type mass flowmeter and a vibration type density meter. Since the Coriolis mass flowmeter has substantially the same configuration as the vibration type flowmeter, the mass flowmeter will be described in detail in this embodiment.

In each of the drawings, a mass flowmeter 1 includes a closed box-shaped casing 2, a pair of pipe lines 3 and 4 housed in the casing 2, and a pair of pipe lines 3 and 4 at both ends. It is composed of inflow side and outflow side manifolds 5 and 6 connected to each other.

The pair of pipe lines 3 and 4 extend parallel to each other, and the inflow side and outflow side end faces 2 of the box-shaped casing 2 are provided.
Flange 3a, 3b, 4a, 4b as an inflow side and an outflow side connection part is provided in the edge part projected from a, 2b. In the casing 2, a pair of pipe lines 3,
4 is a straight tubular sensor tube 7 through which the fluid to be measured flows,
8, the inflow side bellows 9 and 10 connected to the upstream end portions of the straight tubular sensor tubes 7 and 8, and the outflow side bellows 1 connected to the downstream end portions of the straight tubular sensor tubes 7 and 8.
It consists of 1 and 12.

Since the straight tubular sensor tubes 7 and 8 are straight tubes and do not require bending, the pressure loss when the fluid flows is small and the manufacturing cost is low.
In addition, the straight tubular sensor tube 7,
The fluid to be measured attached to the inner wall of 8 can be efficiently removed.

Since each of the bellows 9 to 12 has a bellows shape in which a large diameter portion and a small diameter portion are alternately formed,
For example, when compression or tensile stress acts in the axial direction (pipeline extending direction), the R portions of the large diameter portion and the small diameter portion elastically deform and expand and contract.

Therefore, when the straight sensor tubes 7 and 8 expand and contract in the axial direction due to thermal expansion or contraction due to temperature change, the expansion and contraction amount of each of the bellows 9 disposed at both ends is as small as possible.
It is absorbed by the stretching operation of 12. Therefore, the straight tube sensor tubes 7 and 8 are configured so as not to be deformed by thermal expansion or thermal contraction or to be applied with an extra load, and the deterioration of measurement accuracy due to temperature change is prevented.

Further, between the both ends of the straight sensor tubes 7 and 8, the plate-shaped supporting members 13 and 14 are penetrated, and the outer peripheries thereof are fixed to the supporting members 13 and 14 by brazing or the like.
Therefore, the pair of straight tubular sensor tubes 7 and 8 are brazed and fixed to the inflow side and outflow side end surfaces 2a and 2b of the casing 2, and also fixed to the support members 13 and 14, so that a constant interval is maintained. As it is, it is horizontally traversed in the casing 2, and vibrates with supporting members 13 and 14 as fulcrums, as will be described later.

Reference numeral 15 denotes a vibration exciter, which has a structure substantially similar to that of an electromagnetic solenoid, and is provided between the pair of straight tube sensor tubes 7 and 8 at a substantially middle portion thereof. That is, the shaker 15 is
Coil 15 provided on one straight sensor tube 7
a and a magnet 15b provided on the other straight tubular sensor tube 8, and a direction in which a pair of straight tubular sensor tubes 7 and 8 are moved closer to and away from each other by the repulsive force of the magnet 15b against the electromagnetic force generated from the coil 15b. (Y
(Direction).

Reference numeral 16 denotes an upstream (inflow side) pickup, which is provided between the straight tubular sensor tubes 7 and 8 on the upstream side (inflow side) of the vibrator 15.

Reference numeral 17 denotes a pickup on the downstream side (outflow side), which is provided between the straight tubular sensor tubes 7 and 8 on the downstream side (outflow side) of the vibrator 15.

The pickups 16 and 17 are the vibrators 1 respectively.
5 is a vibration sensor for detecting the displacement of the straight tubular sensor tubes 7, 8 vibrated by 5. That is, pickup 1
Reference numerals 6 and 17 have the same configuration as that of the electromagnetic solenoid, and are coils 16a provided on one straight tubular sensor tube 7,
17a, and magnets 16b, 17b provided on the other straight tubular sensor tube 8 respectively. Therefore, the magnet 16 is accompanied by the vibration of the straight sensor tubes 7 and 8.
b, 17b and the coils 16a, 17a move relative to each other, and the electromotive force of the voltage corresponding to this relative displacement amount is applied to the coils 16a, 1a.
7a.

The inflow side manifold 5 is connected to the upstream side pipe 18
And the inflow side ends of the pipe lines 3 and 4 are disposed so as to intervene. The inflow-side manifold 5 has an inflow port 5a that communicates with the upstream pipe 18, and connection ports 5b and 5c that branch into two branches from the inflow port 5a and communicate with the pipe lines 3 and 4. or,
A flange 5d connected to the flange 18a of the upstream pipe 18 is provided at one end having the inflow port 5a, and the flange 3 of the pipe lines 3, 4 is provided at the other end having the connection ports 5b, 5c.
flange 5 as an inflow side connecting portion connected to a and 4a
e, 5f are provided.

The outlet side manifold 6 has a downstream side pipe 19
And the outflow side ends of the pipe lines 3 and 4 are arranged so as to be interposed. The outflow-side manifold 6 has an outlet 6a that communicates with the downstream pipe 19, and connection ports 6b and 6c that branch into two branches from the outlet 6a and communicate with the conduits 3 and 4.
A flange 6d connected to the flange 19a of the downstream pipe 19 is provided at one end having the outflow port 6a, and the flanges 3b, 4b of the pipelines 3, 4 are provided at the other end having the connection ports 6b, 6c. There are provided flanges 6e and 6f as outflow-side connecting portions connected to.

Normally, the flanges 3a, 3 of the pipelines 3, 4 are
b, 4a, 4b and inflow side and outflow side manifolds 5, 6
Flanges 5d to 5f, 6d to 6f and the upstream pipe 1
No. 8 flange 18a, downstream side pipe 19 flange 19a
Are fixed by fastening bolts 20 and nuts 21 between flanges facing each other with a ring-shaped packing (not shown) interposed.

At the time of flow rate measurement, the pair of straight tubular sensor tubes 7 and 8 are vibrated by the vibration exciter 15 in the direction of approaching and separating (Y direction). The fluid to be measured supplied from the upstream pipe 18 flows into the inflow port 5a of the inflow side manifold 5, and the connection ports 5b and 5c are bifurcated from the inflow port 5a.
It reaches a pair of pipe lines 3 and 4. In the inflow side manifold 5, the flow rate to the connection port 5b and the flow rate to the connection port 5c are
The flow rates are divided so that the flow rates become equal to each other so that the flow rates flowing through the pair of straight tubular sensor tubes 7 and 8 become the same.

Furthermore, the fluid to be measured passes through the inflow side bellows 9 and 10 of the pipe lines 3 and 4 and flows into the pair of straight tubular sensor tubes 7 and 8. A pair of straight tubular sensor tubes 7,
The fluid to be measured that has passed through 8 passes through the outflow side bellows 11 and 12 and reaches the connection ports 6b and 6c of the outflow side manifold 6. Then, the fluid to be measured merged from the connection ports 6b and 6c flows out to the downstream side pipe 19 from the outlet 6a.

As described above, when the fluid flows through the vibrating straight tubular sensor tubes 7 and 8, a Coriolis force having a magnitude corresponding to the flow rate is generated. Therefore, an operation delay occurs between the inflow side and the outflow side of the straight tubular sensor tubes 7 and 8,
As a result, a phase difference appears in the output signals of the pickups 16 and 17.

Therefore, since the phase difference is proportional to the flow rate, the arithmetic unit (not shown) calculates the flow rate based on the phase difference between the output signals from the pickups 16 and 17.

In the mass flowmeter 1 having the above structure, the mass flow rate is measured while the fluid to be measured is flown in the vibrating straight tubular sensor tubes 7 and 8. Therefore, not only liquid or gas but also viscous slurry fluid The mass flow rate of can also be measured. However, when switching to measure different types of fluids to be measured depending on time, such as in a food production line, or moving to each site like a construction site to measure cement etc., the work at that site When finished, it may be moved to the next site.

As described above, when the type of the fluid to be measured is changed or the device itself needs to be moved, the fluid to be measured is mixed with another fluid to be measured or the fluid to be measured adhered to the inner walls of the pipe lines 3 and 4. Since the fluid solidifies, it is necessary to remove the fluid to be measured that remains in the conduits 3 and 4.

However, in the mass flowmeter 1 having the above construction, as shown in FIG. 4, the casing 2 for accommodating the straight tubular sensor tubes 7 and 8 can be separated from the inflow side and outflow side manifolds 5 and 6. Therefore, when it is necessary to clean the inside of the pipelines 3 and 4 as described above, the on-off valves (not shown) arranged in the upstream pipe 18 and the downstream pipe 19 are provided.
To close the flanges 3a, 3b, 4 of the pipelines 3, 4
bolts 20 for connecting the flanges 5e, 5f, 6e and 6f of the inflow side and outflow side manifolds 5 and 6, respectively.
Loosen the nut 21. With this, the connection between the flanges can be released, and the casing 2 can be removed from the inflow side and outflow side manifolds 5, 6.

The pipe lines 3 and 4 arranged in the casing 2 are straight tubular sensor tubes 7 and 8 and a bellows 9.
Since ~ 12 are formed in a straight tubular shape arranged coaxially, the cleaning liquid is sprayed into the pipe lines 3 and 4 from the opening portions of the flanges 3a, 3b, 4a and 4b, or a brush (not shown) is used. ), The fluid to be measured attached to the inner walls of the straight sensor tubes 7 and 8 and the bellows 9 to 12 can be removed.

After the cleaning work in the pipe lines 3 and 4 is completed in this way, the casing 2 is mounted again between the inflow side and outflow side manifolds 5 and 6, and the bolts 20 are provided between the flanges.
Connect with the nut 21. Then, the upstream pipe 18,
The on-off valve (not shown) arranged in the downstream side pipe 19 can be opened to restart the fluid supply to the pipe lines 3 and 4.

Therefore, in the food production line, the previous fluid to be measured remaining in the pipelines 3 and 4 at the time of changing the food type is efficiently cleaned and sanitary, and foods of different types are mass flowmeters. 1 can prevent mixing. Further, even when it is necessary to move the mass flowmeter 1 as in the case of measuring cement or the like, the casing 2 can be removed in a short time to clean the inside of the pipe lines 3 and 4, so that the pipes can be moved during the movement. It is possible to prevent the passages 3 and 4 from being blocked by cement.

Moreover, since the casing 2 can be separated from the pipe passage by simply loosening the bolt 20 and the nut 21,
For example, when the vibration exciter 15 or the pickups 16 and 17 are inspected or repaired, the work is easy and the maintenance is easy, and the inspection and repair can be performed in a short time.

Further, since only the casing 2 can be removed while the inflow side and outflow side manifolds 5 and 6 are connected to the upstream side pipe 18 and the downstream side pipe 19, for example, the straight tubular sensor tubes 7 and 8 and the like. When the bellows 9 to 12 are damaged, the entire casing 2 can be replaced and repaired in a short time.

In the above embodiment, the pipe end of the casing is connected to the inflow side and outflow side manifolds via the flange, but the invention is not limited to this. For example, a connecting structure other than the flange (for example, screw type, Alternatively, it is of course possible to employ a quick type connection mechanism or the like).

[0043]

As described above, in the vibration type measuring apparatus according to the present invention, the inflow side and outflow side connecting portions are provided at the inflow side end and the outflow side end of the pair of pipes protruding to the outside of the casing. Therefore, the casing accommodating the pair of pipelines can be easily removed from the piping system passage only by separating the inflow side end portion and the outflow side end portion from the inflow side manifold and the outflow side manifold. Moreover, since the pair of straight tubular sensor tubes housed in the casing are formed in a straight tubular shape,
The inside of the pipeline can be easily cleaned, and the fluid to be measured remaining in the pipeline can be removed in a short time. Further, the pressure loss of the fluid in the straight tube sensor tube is small, and the straight tube sensor tube is easily processed, so that the manufacturing cost can be reduced. Furthermore, since the inside of the straight sensor tube can be easily washed, the previous food is removed from the pipeline when changing the type of food, even when used in a production line where food is used as the fluid to be measured. By doing so, it has features such as hygiene.

[Brief description of drawings]

FIG. 1 is an exploded perspective view showing a Coriolis mass flowmeter as an embodiment of a vibration type measuring apparatus according to the present invention.

FIG. 2 is a transverse cross-sectional view showing a configuration inside a casing.

FIG. 3 is a plan view showing a state in which a mass flowmeter is arranged in the middle of piping.

FIG. 4 is a plan view showing a state where the casing is removed from the inflow side and outflow side manifolds.

[Explanation of symbols]

 1 Mass flowmeter 2 Casing 3,4 Pipe line 5 Inflow side manifold 6 Outflow side manifold 7,8 Straight tubular sensor tube 9,10 Inflow side bellows 11,12 Outflow side bellows 15 Vibrator 16,17 Pickup

Claims (1)

[Claims] 1. A hermetically sealed casing, one end of which is opened as an inflow side connecting portion to the outside from an inflow side end of the casing, and the other end of which is penetrated into the casing to the outside of an outflow side end of the casing. A pair of straight tubular sensor tubes opened as outlet side connection parts, a vibrator provided in the casing for vibrating the pair of straight tubular sensor tubes, and a straight tube accompanying vibration of the pair of straight tubular sensor tubes. A pair of vibration sensors for detecting displacements on the upper and lower sides of the sensor tube, an inflow side manifold connected to the inflow side connection part, and an outflow side manifold connected to the outflow side connection part. Vibration type measuring device.