CN110672166A - A Multipoint Measurement Bitoba Flowmeter - Google Patents

Abstract

The invention discloses a multi-point measurement Pitoba flowmeter, comprising a plurality of Pitoba flow sensors, a plurality of differential pressure transmitters and a flow totalizer. The Pitoba flow sensor has a pressure-taking head, and also includes a Install the short pipe, a plurality of Pitoba flow sensors are evenly spaced along the circumferential direction of the installation short pipe and vertically fixed on the short installation pipe, the pressure-taking head of each Pitoba flow sensor is located in the short installation pipe, and each The distances from the full pressure hole at the bottom of the pressure head of the Pitoba flow sensor to the axis of the installation short pipe are not equal; the signal output end of each Pitoba flow sensor is connected to the signal input end of the corresponding differential pressure transmitter. The signal output ends of the plurality of differential pressure transmitters are respectively connected with the corresponding signal input ends of the flow totalizer. The present invention is equivalent to using a plurality of different Pitoba flow meters to measure the fluid flow in the same pipeline, and the measurement result is relatively accurate.

Description

A Multipoint Measurement Bitoba Flowmeter

technical field

The invention relates to a Bitoba flowmeter, in particular to a multipoint measurement Bitoba flowmeter.

Background technique

At present, there are many types of flow measuring devices for measuring the fluid flow in the pipeline. The Pitoba flowmeter is widely used to measure the flow of the fluid in the pipeline due to its simple structure, convenient installation and relatively high measurement accuracy. Pitoba flowmeter is mainly composed of Pitoba flow sensor, differential pressure transmitter and flow totalizer. When using, the Pitoba flow sensor is inserted vertically into the pipeline from the side wall of the pipeline. The full pressure hole of the pressure head is facing the inflow direction of the fluid, and the static pressure hole is facing the outflow direction of the fluid. When the fluid flows in the pipeline, the full pressure interface and static pressure at the upper end of the pressure guiding pipe of the Bitopa flow sensor The interface outputs the total pressure and static pressure signals of the fluid flowing in the pipeline respectively. The differential pressure transmitter converts the total pressure and static pressure signals of the fluid in the pipeline transmitted by the Bitopa flow sensor into a standard current signal of 4~20mA and then transmits it. For the flow totalizer, according to the total pressure and static pressure of the fluid flowing in the pipeline, the flow rate of the fluid in the pipeline can be finally calculated in the flow totalizer according to the principle of fluid mechanics.

When the Bitopa flowmeter in the above-mentioned prior art measures the fluid flow in the pipeline, the measurement accuracy of the Bitopa flow sensor determines the measurement accuracy of the final fluid flow in the pipeline. The larger the error, the larger the error of the final measurement result. There are many reasons for the inaccuracy of the full pressure or static pressure signal. For example, when the full pressure or static pressure hole has scaling on the inner wall of the hole, excessive dust accumulation and crystallization, the output full pressure or static signal will change greatly, resulting in the measurement of The result has a large error.

SUMMARY OF THE INVENTION

The technical problem to be solved by the present invention is to provide a multi-point measurement Pitoba flowmeter that can obtain relatively accurate measurement results when measuring the fluid flow in the pipeline.

In order to solve the above technical problems, the present invention provides a multi-point measurement Bitoba flowmeter, including a Bitoba flow sensor, a differential pressure transmitter and a flow totalizer. There are full pressure channels and static pressure channels with axes parallel to each other and located on opposite sides of the pressure taking head. The opposite sides of the lower part of the pressure taking head have full pressure holes and static pressure channels which are respectively communicated with the full pressure channel and the static pressure channel. hole, the signal output end of the Bitopa flow sensor is connected with the signal input end of the differential pressure transmitter, the signal output end of the differential pressure transmitter is connected with the signal input end of the flow totalizer, and the Bitopa flow sensor is connected with the signal input end of the differential pressure transmitter. The number of flow sensors is multiple, and correspondingly, the number of differential pressure transmitters is also multiple. It also includes installation short pipes. Multiple Pitoba flow sensors are evenly spaced and vertically fixed along the circumferential direction of the installation short pipes. Installed on the installation short pipe, the pressure head of each Pitoba flow sensor is located in the installation short pipe, and the distance from the full pressure hole at the bottom of the pressure head of each Pitoba flow sensor to the installation short pipe axis is not equal; The signal output end of each Pitoba flow sensor is connected with the signal input end of the corresponding differential pressure transmitter, and the signal output ends of the plurality of differential pressure transmitters are respectively corresponding to the signals of the flow totalizer. connected to the input.

As an improvement of the present invention, the axes of the full pressure channels in the pressure-taking heads of the plurality of Pitoba flow sensors are located in the same plane, and the axes of the static pressure channels are located in another plane.

Using the multi-point measurement Pitoba flowmeter of the above structure, when in use, the installation short pipe in the present invention is connected with the matched pipeline to be measured. The present invention is equivalent to using multiple different Pitoba flowmeters to measure the same pipeline The measurement result is the average of all measurement results, the measurement result is relatively accurate, and the measurement accuracy is high; when a set of differential pressure signals output by a Bitopa flow sensor is transmitted to the corresponding differential pressure transmitter to When the difference between the flow value accumulated by the flow totalizer and the average value of all measurement results exceeds a certain range, the totalizer can output the average value of other measurement results, and still obtain relatively accurate measurement results. In the present invention, the Pitoba flow sensor whose output measurement result has a larger error can be repaired or replaced during the maintenance of the flow meter.

Description of drawings

The present invention will be further described in detail below in conjunction with the accompanying drawings.

FIG. 1 is a schematic diagram of the structure of a multi-point measurement Pitoba flowmeter of the present invention.

FIG. 2 is an enlarged schematic view of the structure at I in FIG. 1 .

FIG. 3 is a schematic cross-sectional view along the line A-A in FIG. 2 .

Detailed ways

Referring to Figures 1 to 3, a multi-point measurement Pitoba flowmeter of the present invention includes a Pitoba flow sensor 10, a differential pressure transmitter 20 and a flow totalizer 30. The Pitoba flow sensor has a pressure-taking head 11. There are full pressure channel 12 and static pressure channel 13 in the pressure taking head 11 whose axes are parallel to each other and located on opposite sides of the pressure taking head. The full pressure hole 14 and the static pressure hole 15 communicated with the channel 13, the signal output end of the Bitopa flow sensor 10 is connected with the signal input end of the differential pressure transmitter 20, and the signal output end of the differential pressure transmitter 20 Connected to the signal input end of the flow totalizer 30, the number of the Bitobar flow sensors 10 is multiple, and correspondingly the number of the differential pressure transmitter 20 is also multiple, and also includes the installation of the short pipe 1 , a plurality of Pitoba flow sensors 10 are evenly spaced and vertically fixed on the installation short pipe 1 along the circumferential direction of the installation short pipe 1, and the pressure-taking head 11 of each Pitoba flow sensor is located in the installation short pipe 1, And the distances from the full pressure hole 14 at the bottom of the pressure head of each Pitoba flow sensor to the axis of the installation short pipe 1 are not equal. The distances of the axes are also not equal; the signal output end of each Pitoba flow sensor 10 is connected with the signal input end of the corresponding differential pressure transmitter 20, and the signal output ends of the plurality of differential pressure transmitters 20 are respectively connected with The corresponding signal input ends of the flow totalizer 30 are connected. Preferably, the axes of the full-pressure channels 12 in the pressure head 11 of the plurality of Pitoba flow sensors 10 are located in the same plane, and the axes of the static pressure channels 13 are located in another plane. The axes of the full pressure channel 12 and the static pressure channel 13 in the pressure taking head are parallel to each other, so these two planes are also parallel to each other.

The differential pressure between the positive pressure passages and the negative pressure passages is due to the different proportions of the insertion depths in the pipes. When there is medium flowing, the flow velocity between the positive pressure passages and the negative pressure passages is different due to the difference in the flow velocity at the center of the pipe and the flow velocity at the edge of the pipe. There is a certain proportion of the differential pressure between the two. When the scale is formed in the pipeline, the inner diameter of the pipeline decreases. At this time, the proportion of the sensor inserted in the pipeline changes, and the differential pressure between each positive pressure channel and The calculator calculates the pipeline fouling by recording the relationship between the differential pressure proportional relationship and the pipeline fouling situation. Thereby, the flow area of the medium is calculated and corrected automatically.

Claims (2)

1. The utility model provides a multi-point measurement Pitot flowmeter, includes Pitot flow sensor (10), differential pressure transmitter (20) and flow totalizer (30), Pitot flow sensor has pressure of getting head (11), gets and has axis parallel to each other and be located full pressure passageway (12) and static pressure passageway (13) of getting the pressure head relative both sides in pressure head (11), gets relative both sides of pressure head (11) lower part and has full pressure hole (14) and static pressure hole (15) that are linked together with full pressure passageway (12) and static pressure passageway (13) respectively, the signal output part of Pitot flow sensor (10) links to each other with the signal input part of differential pressure transmitter (20), and the signal output part of differential pressure transmitter (20) links to each other with the signal input part of flow totalizer (30), its characterized in that: the device comprises a plurality of Pitotbar flow sensors (10), a plurality of differential pressure transmitters (20) and an installation short pipe (1), wherein the plurality of Pitotbar flow sensors (10) are uniformly distributed and vertically fixed on the installation short pipe at intervals along the circumferential direction of the installation short pipe (1), a pressure taking head (11) of each Pitotbar flow sensor is positioned in the installation short pipe (1), and the distances from a full pressure hole (14) at the lower part of the pressure taking head of each Pitotbar flow sensor to the axis of the installation short pipe (1) are different; the signal output end of each Pitotbar flow sensor (10) is connected with the signal input end of the corresponding differential pressure transmitter (20), and the signal output ends of the differential pressure transmitters (20) are respectively connected with the signal input ends corresponding to the flow totalizer (30).

2. The multi-point measurement pitot-bar flow meter of claim 1, wherein: the axes of the full pressure channels (12) in the pressure taking heads (11) of the Pitot-bar flow sensors (10) are positioned in the same plane, and the axes of the static pressure channels (13) are positioned in another plane.

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