CN216925716U

CN216925716U - Non-contact type measuring device for liquid level

Info

Publication number: CN216925716U
Application number: CN202220473240.3U
Authority: CN
Inventors: 郭一平; 杨晓章; 金明杰
Original assignee: Zhejiang Tiantai Pharmaceutical Co ltd
Current assignee: Zhejiang Tiantai Pharmaceutical Co ltd
Priority date: 2022-03-03
Filing date: 2022-03-03
Publication date: 2022-07-08
Anticipated expiration: 2032-03-03

Abstract

The utility model discloses a non-contact measuring device for liquid level, which is used for measuring the liquid level in a storage tank or a ground pool and comprises an empty pipe extending into liquid, wherein the bottom of the empty pipe is an open end, the top of the empty pipe is a sealed end, the upper part of the side wall is connected with a branch pipe, the tail end of the branch pipe is connected with a pressure detection device, and a nitrogen charging valve is arranged on the branch pipe. The non-contact measuring device does not contact liquid, is convenient to maintain and use, and improves the measuring precision.

Description

Non-contact type measuring device for liquid level

Technical Field

The utility model belongs to the field of liquid level measurement, and particularly relates to a non-contact type liquid level measuring device.

Background

Level measurement is required in many fields, for example: irrigation of farmland, hydraulic engineering, hydrological observation and monitoring, pharmaceutical and chemical engineering, water treatment and the like. At present, a plurality of devices for measuring liquid level mainly comprise a magnetic turning plate liquid level meter, a differential pressure transmitter, a magnetic float liquid level meter, an ultrasonic liquid level meter and the like.

The magnetic turning plate liquid level meter and the differential pressure transmitter are mostly required to be in contact with liquid through holes formed in the lower side of the storage tank, and the magnetic turning plate liquid level meter is developed according to the buoyancy principle and the magnetic coupling effect. When the liquid level in the measured container rises and falls, the magnetic floater in the liquid level meter body pipe also rises and falls, the permanent magnetic steel in the floater is transmitted to the magnetic column turning indicator through magnetic coupling, and the red column and the white column are driven to turn over for 180 degrees, so that the indication of the liquid level is realized. The two types of liquid level measuring devices have the defect that the liquid level measuring devices need to be in contact with liquid, and if the liquid in contact with the liquid is dangerous goods or high-temperature liquid, the devices are inconvenient to maintain and calibrate daily. If the calibration period is up, the appliance is damaged and liquid is in the tank, the assembly and disassembly are inconvenient.

The magnetic float level meter and the ultrasonic level meter have the same defects, and the principle of the ultrasonic level meter is a level measuring instrument manufactured according to the proportion relation between the time required by ultrasonic waves from emission to receiving of liquid level echoes and the height of the liquid level. The ultrasonic wave detection device mainly comprises a transducer for generating ultrasonic waves, a transducer for receiving the ultrasonic waves, a time interval detection circuit and the like. The two types of liquid level measuring devices need to be provided with holes on the tank top, and at present, a chemical storage tank, a ground pool or nitrogen filling protection or sealing is carried out to prevent gas leakage in the tank, so that the two types of liquid level measuring devices are inconvenient to disassemble and assemble (overhaul or calibrate).

Therefore, the liquid level measuring device suitable for the chemical field is urgently needed to be developed, the inconvenience can be avoided, and the maintenance and the use are more convenient.

SUMMERY OF THE UTILITY MODEL

The utility model provides a non-contact type measuring device for liquid level, which does not contact liquid, is convenient to maintain and use and has higher measuring precision.

In order to solve the above problems, the present invention provides the following technical solutions:

the utility model provides a non-contact measuring device of liquid level, non-contact measuring device is arranged in measuring the liquid level in storage tank or the ground pond, including stretching into the hollow tube in the liquid, the bottom of hollow tube is the open end, and the top is sealed end, and lateral wall upper portion even has the branch pipe, and the branch pipe end even has pressure measurement, has seted up on the branch pipe and has filled the nitrogen valve.

The measuring device of the utility model is characterized in that a hollow pipe with proper pipe diameter and insertion length close to the bottom and with a sealed tail end is installed and inserted above a tank or a pool, and the detection is carried out by utilizing the principle of equal pressure formed by the pressure in the pipe and the liquid level height of liquid. In the calibration and comparison processes, nitrogen is introduced into the nitrogen filling valve to supplement the problem of liquid level rise in the pipe caused by factors such as gas dissolution and temperature change (the liquid level rise in the pipe can cause inaccurate measurement), so that the measurement error is reduced, and the detection precision is improved.

Preferably, the hollow pipe is fixed on the top of the storage tank or the ground pool through a tank top flange.

Preferably, the pressure detection device is a pressure transmitter or a differential pressure transmitter;

and a port of the pressure transmitter or the differential pressure transmitter is provided with a block valve.

Preferably, the pressure detection device is a differential pressure transmitter, one end of the differential pressure transmitter is connected with the hollow pipe, and the other end of the differential pressure transmitter is communicated with the space above the liquid level of the storage tank or the ground pool through a connecting pipeline. At the moment, the pressure difference transmitter can detect the pressure difference between the liquid level in the pipe and the liquid level in the storage tank or the ground pool, so that the liquid level height is obtained, the interference of other factors is small, and the detection precision can be greatly improved.

Preferably, the connecting pipeline is fixed on the top of the storage tank or the ground pool through a tank top flange, and a closing valve is arranged on the connecting pipeline.

Preferably, the length of the inner pipe is approximately equal to the effective inner height of the storage tank or the ground pool. Therefore, the detection range of the measuring device is large, and the detection function can be realized even if the liquid level is low.

Compared with the prior art, the utility model has the beneficial effects that:

the measuring device of the utility model is characterized in that a hollow pipe with proper pipe diameter and insertion length close to the bottom and with a sealed tail end is installed and inserted above a tank or a pool, and the principle of pressure equalization formed by the pressure in the pipe and the liquid level height of liquid is utilized. The signal output corresponding to the liquid level height can be obtained only by measuring the pressure in the pipe by the pressure transmitter or measuring the pressure difference between the pipe and the tank top by the pressure difference transmitter, and the monitoring purpose can be realized by matching with a corresponding display and control instrument.

Drawings

FIG. 1 is a schematic diagram of a method of carrying out the apparatus for non-contact measurement of liquid level according to the present invention;

FIG. 2 is a schematic structural view of another embodiment of the non-contact liquid level measuring device of the present invention; in the figure, 1: a storage tank; 2: a liquid inlet pipeline; 3: a liquid outlet; 4: empty pipe; 5: a flange; 6: an open end; 7: sealing the end; 8: a nitrogen charging valve; 9: a differential pressure transmitter; 10: a pressure transmitter; 11: a nitrogen seal valve; 12: a block valve.

Detailed Description

The utility model is further described below with reference to the specific drawings.

Fig. 1 is a schematic structural diagram of an embodiment of a non-contact liquid level measuring device of the present invention, and as shown in fig. 1, the measuring device is used for detecting a liquid level of a storage tank 1, a liquid inlet is arranged at the top of the storage tank 1, a liquid inlet pipeline 2 is connected to the liquid inlet, the liquid inlet pipeline 2 is fixed to the top of the storage tank through a flange, the liquid inlet pipeline 2 extends into the vicinity of the bottom of the storage tank, a liquid outlet 3 is arranged at the bottom of a side wall, and a pressure release valve may be further arranged at the top of the storage tank to prevent an excessive pressure in the storage tank.

In fig. 1, the non-contact measuring device comprises a hollow pipe 4 extending into the liquid, the hollow pipe 4 being fixed to the top of the tank by a flange 5, wherein the bottom is an open end 6 and the top is a sealed end 7. The upper side wall of the hollow pipe 4 is connected with a branch pipe, the branch pipe is provided with a nitrogen charging valve 8, the tail end of the branch pipe is connected with a differential pressure transmitter 9, and an isolating valve is arranged between the branch pipe and the differential pressure transmitter 9. The other end of the differential pressure transmitter 9 is communicated with the space above the liquid level of the storage tank or the ground pool through a connecting pipeline, the connecting pipeline is fixed with the top of the tank through a flange 5, and meanwhile, a closing valve 12 and a nitrogen sealing valve 11 are arranged on the connecting pipeline. The differential pressure transmitter is connected to an external control instrument for converting the pressure value into a level value.

During measurement, if liquid enters the empty pipe due to temperature change or gas solvent, inert gas can be introduced into the empty pipe through the diazo valve to discharge the liquid (redundant air can be discharged from the open end at the bottom of the empty pipe, enters the upper part of the storage tank and then is discharged from the pressure release valve), so that the situation that no liquid exists in the empty pipe is ensured. Then, closing valves on pipelines at two ends of the differential pressure transmitter are opened, the pressure difference at the two ends is measured, the pressure difference is just the same as the pressure difference between the liquid level at the bottom of the empty pipe and the liquid level in the storage tank, then the pressure difference is transmitted to a control instrument, and the control instrument converts the pressure difference into a liquid level value.

Fig. 2 shows another embodiment of the non-contact measuring apparatus according to the present invention (the structure of the tank and the like is omitted). Compared with the figure 1, the end part of the branch pipe of the measuring device is connected with a pressure transmitter 10 to replace a differential pressure transmitter, the pressure value inside the hollow pipe is measured directly through the pressure transmitter 10, the liquid level height is calculated according to the pressure value, the change of the air pressure at the upper part of the storage tank is not considered, therefore, the measuring precision is slightly lower than that of the embodiment of the figure 1, but the measuring device has a simpler structure and is more suitable for the requirement of lower precision, and therefore, the measuring device also has higher application value.

The foregoing is illustrative of the preferred embodiments of the present invention, and is not to be construed as limiting the utility model in any way; the present invention may be readily implemented by those of ordinary skill in the art as illustrated in the accompanying drawings and described above; however, those skilled in the art should appreciate that they can readily use the disclosed conception and specific embodiments as a basis for designing or modifying other structures for carrying out the same purposes of the present invention without departing from the scope of the utility model as defined by the appended claims; meanwhile, any changes, modifications, and evolutions of the equivalent changes of the above embodiments according to the actual techniques of the present invention are still within the protection scope of the technical solution of the present invention.

Claims

1. The utility model provides a non-contact measuring device of liquid level, non-contact measuring device is arranged in measuring the liquid level in storage tank or the ground pond, its characterized in that, including stretching into the empty pipe in the liquid, the bottom of empty pipe is the open end, and the top is sealed end, and lateral wall upper portion even has the branch pipe, and the branch pipe end even has pressure measurement, has seted up on the branch pipe and has filled the nitrogen valve.

2. A non-contact measuring device according to claim 1, wherein the hollow pipe is secured to the top of the tank or basin by a tank top flange.

3. The noncontact measuring device of claim 1, wherein said pressure detecting means is a pressure transmitter or a differential pressure transmitter;

4. The non-contact measuring device of claim 3, wherein the pressure detecting device is a differential pressure transmitter, one end of the differential pressure transmitter is connected with the hollow pipe, and the other end of the differential pressure transmitter is communicated with the space above the liquid level of the storage tank or the ground pool through a connecting pipeline.

5. A non-contact measuring device according to claim 4, wherein the connecting pipe is fixed on the top of the storage tank or the ground pool by a tank top flange, and the connecting pipe is provided with a closing valve.

6. A non-contact measuring device according to claim 1 wherein the length of the hollow pipe is substantially equal to the effective internal height of the tank or pond.