CN116263348A

CN116263348A - Detection method, detection device and flowmeter for measuring pollutants in pipeline

Info

Publication number: CN116263348A
Application number: CN202111523442.0A
Authority: CN
Inventors: 林志蒙; 丁渊明; 陈倩; 陈红
Original assignee: TANCY INSTRUMENT GROUP CO Ltd; Goldcard Smart Group Co Ltd
Current assignee: TANCY INSTRUMENT GROUP CO Ltd; Goldcard Smart Group Co Ltd
Priority date: 2021-12-14
Filing date: 2021-12-14
Publication date: 2023-06-16

Abstract

The application provides a detection method, detection device and flowmeter of inside pollutant of measurement pipeline, and detection method of inside pollutant of measurement pipeline includes: determining that the current flow rate in the metering pipeline of the flowmeter meets detection conditions; acquiring a current detection signal gain value of a detection piece positioned on a first detection path in a metering pipeline; determining a detection signal gain difference value according to the current detection signal gain value and the set detection signal gain value; and judging the size relation between the detection signal gain difference value and the set detection threshold value, if the detection signal gain difference value is larger than or equal to the set detection threshold value, determining that the first detection path in the metering pipeline has pollutants, and if the detection signal gain difference value is smaller than the set detection threshold value, determining that the first detection path in the metering pipeline has no pollutants. The utility model discloses a pollution condition that can the inside of measurement pipeline of real-time detection flowmeter improves the measurement precision of flowmeter.

Description

Detection method, detection device and flowmeter for measuring pollutants in pipeline

Technical Field

The application relates to the technical field of detection devices, in particular to a detection method, a detection device and a flowmeter for measuring pollutants in a pipeline.

Background

The ultrasonic flowmeter based on the time difference method adopts a non-contact mode to measure the flow of various liquids or gases, and the working principle is that the ultrasonic flowmeter is based on the transmission of ultrasonic signals between a pair of transducers along a measuring path, and the fluid flow in a metering pipeline is calculated according to the time difference of forward and backward transmission of the ultrasonic signals in flowing fluid.

In the related art, the measurement accuracy of the ultrasonic flowmeter is very sensitive to the condition of the flow field, and under the condition of ideal flow field, the monaural ultrasonic flowmeter can obtain very good measurement accuracy. The flow field condition is affected by the roughness of the inner wall of the metering tube, which, when increased, results in a decrease in the metering accuracy of the ultrasonic flow meter. In this regard, this is generally addressed by periodically checking the state of the inner wall of the metering tube and cleaning the contaminants in time.

The ultrasonic flowmeter of the technical scheme has low metering precision.

Disclosure of Invention

In view of the above problems, the application provides a method and a device for detecting pollutants in a metering pipeline and a flowmeter, which can detect the pollution condition in the metering pipeline of the flowmeter in real time and improve the metering precision of the flowmeter.

In order to achieve the above object, the present application provides the following technical solutions:

a first aspect of an embodiment of the present application provides a method for detecting a contaminant inside a metering pipeline, which is applied to a flowmeter, and the method for detecting the contaminant inside the metering pipeline includes:

determining that a current flow rate in a metering pipeline of the flowmeter meets a detection condition;

acquiring a current detection signal gain value of a detection piece positioned on a first detection path in the metering pipeline;

determining a detection signal gain difference value according to the current detection signal gain value and a set detection signal gain value;

judging the size relation between the detection signal gain difference value and a set detection threshold value, if the detection signal gain difference value is larger than or equal to the set detection threshold value, determining that the first detection path in the metering pipeline has pollutants, and if the detection signal gain difference value is smaller than the set detection threshold value, determining that the first detection path in the metering pipeline has no pollutants.

In one implementation manner, the step of determining that the current flow rate in the metering pipeline of the flowmeter meets the detection condition specifically includes:

Acquiring a current flow velocity value in a metering pipeline of the flowmeter;

judging the magnitude relation between the current flow velocity value and a set flow velocity threshold value;

if the current flow velocity value is greater than or equal to the set flow velocity threshold value, determining that the current flow velocity in the metering pipeline does not accord with the detection condition, and stopping detection;

and if the current flow velocity value is smaller than the set flow velocity threshold value, determining that the current flow velocity in the metering pipeline meets the detection condition.

In one implementation, the set detection threshold includes a first set detection threshold and a second set detection threshold, the first set detection threshold being greater than the second set detection threshold;

the step of determining the size relation between the detection signal gain difference and a set detection threshold, if the detection signal gain difference is greater than or equal to the set detection threshold, determining that the first detection path in the metering pipeline has a pollutant, and if the detection signal gain difference is less than the set detection threshold, determining that the first detection path in the metering pipeline has no pollutant, specifically includes:

judging the magnitude relation between the detection signal gain difference value and a first set detection threshold value;

If the detection signal gain difference value is larger than or equal to the first set detection threshold value, determining to send out first pollution warning information, and stopping detection;

if the detected signal gain difference value is smaller than the first set detection threshold value, judging the magnitude relation between the detected signal gain difference value and a second set detection threshold value;

if the detection signal gain difference value is larger than or equal to the second set detection threshold value, determining to send out second pollution warning information, and stopping detection;

and if the detection signal gain difference value is smaller than the second set detection threshold value, determining that no pollutant exists on the first detection path in the metering pipeline.

In one implementation manner, at least two groups of first detection paths and at least two groups of second detection paths are arranged in the metering pipeline, the first detection paths and the second detection paths are not completely overlapped, and the second detection paths are not intersected with the inner wall of the metering pipeline;

the detection piece is positioned at the superposition part of the first detection path and the second detection path;

after the step of determining that the current flow rate in the metering conduit of the flowmeter meets the detection condition, before the step of acquiring the current detection signal gain value of the detection piece located on the first detection path in the metering conduit, the method further comprises:

Acquiring a current measured signal gain value of the detection piece positioned on the second detection path;

determining a measurement signal gain difference value according to the current measurement signal gain value and a set measurement signal gain value;

judging the magnitude relation between the measurement signal gain difference value and a set measurement threshold value;

if the measurement signal gain difference value is larger than or equal to the set measurement threshold value, determining that the detection piece on the second detection path in the metering pipeline has pollutants, sending out measurement pollution warning information, and stopping detection;

and if the measured signal gain difference value is smaller than the set measurement threshold value, executing the step of acquiring the current detected signal gain value of the detection piece on the first detection path in the metering pipeline.

A second aspect of the embodiments of the present application provides a detection device, using the above method for detecting a contaminant inside a metering pipeline, where the detection device includes a first detection unit, an automatic gain control unit, a detection control unit, and an alarm control unit;

the first detection unit is positioned on the first detection path and comprises a pair of first detection pieces which are mutually a detection transmitting end and a detection receiving end;

The first detection piece is electrically connected with the automatic gain control unit;

the detection control unit is electrically connected with the automatic gain control unit and the alarm control unit.

In one possible embodiment, the first detection path intersects at least one point of the inner wall of the metering conduit.

In one possible embodiment, the first detection path is parallel to the axial direction of the metering tube.

In an implementation manner, the device further comprises a second detection unit, wherein the second detection unit is positioned on a second detection path, the second detection unit comprises a pair of second detection pieces which are a measurement transmitting end and a measurement receiving end, and the second detection pieces are electrically connected with the automatic gain control unit;

the detection device is provided with at least two first detection units and at least two second detection units, the first detection paths and the second detection paths are not completely overlapped, and the second detection paths are not intersected with the inner wall of the metering pipeline;

the first detection piece and the second detection piece are positioned at the superposition part of the first detection path and the second detection path.

In one implementation manner, two second detection units and two first detection units are arranged to form a detection combination, and the two second detection units and the two first detection units of one detection combination are located in the same detection plane;

setting one detection combination, wherein the detection plane of one detection combination passes through the central axis of the metering pipeline;

or, a plurality of detection combinations are provided, the detection planes of the plurality of detection combinations are parallel to each other and are parallel to the central axis of the metering pipeline, or the detection planes of the plurality of detection combinations intersect.

A third aspect of the embodiments of the present application provides a flow meter, including the detection device described above.

The embodiment of the application provides a detection method, a detection device and a flowmeter for measuring pollutants in a pipeline.

According to the method for detecting the pollutants in the metering pipeline, the fact that the current flow rate in the metering pipeline of the flowmeter meets detection conditions is firstly determined, the condition that the gain value of a follow-up current detection signal is influenced due to the fact that the current flow rate is too large is eliminated, and misjudgment is prevented.

And then acquiring a current detection signal gain value of a detection piece on a first detection path in the metering pipeline, and determining a detection signal gain difference value according to the current detection signal gain value and the set detection signal gain value. If the detection signal gain difference value is greater than or equal to the set detection threshold value, the current detection signal gain exceeds the normal detection signal gain range, which indicates that the attenuation degree of the detection signal reaching the detection piece is serious, and proves that the detection signal is influenced by pollutants in the transmission process on the first detection path, and the attenuation degree of the detection signal is aggravated due to the existence of the pollutants, so that the pollutants on the first detection path in the metering pipeline are determined. If the detection signal gain difference value is smaller than the set detection threshold value, the current detection signal gain value is in a normal detection signal gain range, and the attenuation degree of the detection signal reaching the detection piece is in a normal range, so that the transmission of the detection signal on the first detection path is proved to be not influenced by pollutants, the attenuation degree of the detection signal is normal, and no pollutants on the first detection path in the metering pipeline are determined.

The detection device adopts the detection method of the pollutants in the metering pipeline, and comprises a first detection unit, an automatic gain control unit, a detection control unit and an alarm control unit, wherein the first detection unit is positioned on a first detection path, and the automatic gain control unit is electrically connected with a first detection piece of the first detection unit and the detection control unit.

The flowmeter comprises the detection device.

Therefore, the embodiment of the application can detect the pollution condition in the metering pipeline of the flowmeter in real time, ensure the ideal flow field state in the metering pipeline and improve the metering precision of the flowmeter.

The construction of the present application, as well as other objects and advantages thereof, will be more readily understood from the description of the preferred embodiments taken in conjunction with the accompanying drawings.

Drawings

In order to more clearly illustrate the embodiments of the present application or the technical solutions in the prior art, a brief description will be given below of the drawings that are needed in the embodiments or the prior art descriptions, and it is obvious that the drawings in the following description are some embodiments of the present application, and that other drawings can be obtained according to these drawings without inventive effort for a person skilled in the art.

FIG. 1 is a schematic view of a related art ultrasonic flow meter;

FIG. 2 is a schematic flow chart of a method for detecting contaminants in a metering pipeline according to an embodiment of the present disclosure;

FIG. 3 is a schematic flow chart of a method for detecting contaminants in a metering pipeline according to an embodiment of the present disclosure;

FIG. 4 is a schematic structural diagram of a device for detecting contaminants in a metering pipeline according to an embodiment of the present disclosure;

FIG. 5 is a cross-sectional view of the transducer of FIG. 4 in a radial cross-section near the inlet flange;

fig. 6 is a cross-sectional view of the upper plane of fig. 5.

Reference numerals illustrate:

1-an ultrasonic flowmeter;

100-detecting means; 101-a surface body; 102-an inlet flange; 103-an outlet flange; 104-a control unit; 105-metering piping;

110-upper plane; 111-a first transducer; 112-a second transducer; 113-a third transducer; 114-fourth transducers;

120-lower plane; 125-a fifth transducer; 126-sixth transducer; 127-seventh transducer; 128-eighth transducer;

131-a first detection path; 132-a second detection path; 133-a third detection path; 134-fourth detection path;

145-a fifth detection path; 146-sixth detection path; 147-seventh detection path; 148-eighth detection path;

d-vertical distance from the upper plane and the lower plane to the central axis;

an angle between the theta-measuring path and the central axis of the metering pipeline;

d-inner diameter of ultrasonic flowmeter;

l-channel length;

t _up -ultrasound downstream transmission time;

t _down ultrasonic counter-current transmission time.

Detailed Description

In the related art, referring to fig. 1, a measurement pipe 105 of an ultrasonic flowmeter 1 is horizontally provided, and a fluid in the measurement pipe 105 flows in a direction indicated by an open arrow. A pair of transducers (first transducer 111 and second transducer 112) are disposed on opposite sides of the metering conduit 105, the connection lines of the pair of transducers forming a measurement path, the measurement path having an angle θ with the central axis of the metering conduit 105. The pair of transducers are a measurement transmitting end and a measurement receiving end, and ultrasonic signals are transmitted between the pair of transducers in a downstream and a countercurrent mode in flowing fluid along a measurement path. Due to the influence of the flow velocity of the fluid, the forward and backward transmission speeds of the ultrasonic signals in the fluid are different, so that the transmission time of the forward and backward transmission of the ultrasonic signals between a pair of transducers is inconsistent, and a time difference is generated. From this time difference and the structural parameters of the metering conduit 105, the fluid flow velocity v within the metering conduit can be calculated:

Wherein, the liquid crystal display device comprises a liquid crystal display device,

v: the flow rate of the fluid within the conduit is metered,

l: the length of the channel is determined by the length of the channel,

θ: the included angle between the measuring path and the central axis of the measuring pipeline,

t _up : the ultrasonic countercurrent transmission time is set up,

t _down : ultrasonic downstream transmission time.

The flow rate Q through the metering conduit is the cross-sectional area A and the cross-sectional average velocity of the metering conduit

Is the product of:

q: by metering the flow through the pipe,

a: the cross-sectional area of the conduit is measured,

d: the inner diameter of the ultrasonic flowmeter,

average speed of cross section.

The fluid flow velocity v in the metering conduit is calculated by the time difference in equation one, rather than the cross-sectional average velocity required in calculating the flow Q through the metering conduit in equation two

Under ideal flow field conditions, the average velocity of the cross section can be accurately calculated by using the flow velocity v of the fluid in the metering pipeline>

Under the condition of non-ideal flow field, the average speed of the section cannot be accurately calculated by simply metering the flow velocity v of the fluid in the pipeline>

Therefore, when the ultrasonic flowmeter is installed on site, the flow field at the inlet is required to be close to an ideal flow field, and the flow field in the metering pipeline is generally made to reach an ideal state by means of designing a straight pipe section, a fluid rectifier and the like which are long enough, so that the metering precision of the ultrasonic flowmeter is improved.

After the ultrasonic flowmeter is used for a period of time, due to the influence of factors such as natural gas quality, the inner wall of a metering pipeline of the ultrasonic flowmeter is corroded, the state of a flow field is influenced by rust on the inner wall of the metering pipeline or the adhesion of pollutants, the adhesion and deposition of the pollutants also can lead to the reduction of the cross-sectional area A, and the change can lead to the reduction of the metering precision of the ultrasonic flowmeter. In order to reduce the influence of the contaminants on the metering accuracy of the inner wall of the metering pipeline, the contaminants in the metering pipeline are currently confirmed and cleaned by a periodical inspection method. On one hand, the method needs to disassemble the ultrasonic flowmeter to influence the normal use of the ultrasonic flowmeter, and on the other hand, the method can not find problems in time and can not find and treat pollutants in real time, so that the metering accuracy of the ultrasonic flowmeter is reduced.

Aiming at the technical problems, the embodiment of the application provides a detection method, a detection device and a flowmeter for measuring pollutants in a pipeline.

The detection device for the pollutants in the metering pipeline adopts the detection method for the pollutants in the metering pipeline, and comprises a first detection unit, an automatic gain control unit, a detection control unit and an alarm control unit, wherein the first detection unit is positioned on a first detection path, and the automatic gain control unit is electrically connected with a first detection piece and the detection control unit of the first detection unit.

The flowmeter comprises the detection device.

For the purpose of making the objects, technical solutions and advantages of the present application more apparent, the technical solutions in the embodiments of the present application will be described in more detail below with reference to the accompanying drawings in the preferred embodiments of the present application. In the drawings, the same or similar reference numerals refer to the same or similar components or components having the same or similar functions throughout. The described embodiments are some, but not all, of the embodiments of the present application. The embodiments described below by referring to the drawings are exemplary and intended for the purpose of explaining the present application and are not to be construed as limiting the present application. All other embodiments, which can be made by one of ordinary skill in the art without undue burden from the present disclosure, are within the scope of the present disclosure.

FIG. 2 is a schematic flow chart of a method for detecting contaminants inside a metering pipeline according to an embodiment of the present disclosure; fig. 3 is a further flow chart of a method for detecting a contaminant in a metering pipeline according to an embodiment of the present application.

Referring to fig. 2 and 3, in a first aspect, an embodiment of the present application provides a method for detecting a contaminant inside a metering tube, which is applied to a flowmeter.

As shown in fig. 2, the method for detecting the pollutants in the metering pipeline comprises the following steps:

s1: it is determined that the current flow rate within the metering conduit of the flow meter meets the detection condition.

The current flow rate may be obtained by measuring a measurement component included in the flowmeter itself, or by measuring a measurement component located on the first detection path or the second detection path as described below.

S2: a current detected signal gain value of a detector located on a first detection path within the metering tube is obtained.

The detection signal is transmitted on the first detection path, when the pollutant exists on the first detection path, the detection signal is seriously attenuated, the detection piece on the first detection path is required to amplify the detection signal, and therefore a signal gain value exceeding a normal range is generated. The following description will be given by taking the detection signal as an ultrasonic signal as an example.

It can be understood that the ultrasonic signal is transmitted on a first detection path, and the first detection path is provided with two detection pieces which are a detection signal transmitting end and a detection signal receiving end. The ultrasonic signal may be transmitted downstream along the first detection path or counter-currently along the first detection path.

Wherein, the ultrasonic signals have different attenuation degrees in the transmission process due to different calibers and different installation modes of the ultrasonic flowmeter. Devices at the end of the transmission path receive the echo signal, and when the echo signal amplitude of the ultrasonic signal is small, the attenuated echo signal needs to be amplified, and the amplification factor of the echo signal is called an ultrasonic signal gain value, which is generally expressed in decibels (dB).

In this embodiment, when the ultrasonic signal is transmitted downstream and upstream along the first detection path, the gain value of the ultrasonic signal on the detection member as the end of the transmission path is referred to as the current detection signal gain value.

S3: and determining a detection signal gain difference value according to the current detection signal gain value and the set detection signal gain value.

The set detection signal gain value may be an ultrasonic signal gain value of the detection element on the first detection path, which is obtained when the flow rate of the fluid in the metering pipeline is smaller than the set threshold value and no pollutant is in the metering pipeline at the initial stage of the flowmeter installation.

S4: and judging the magnitude relation between the gain difference value of the detection signal and the set detection threshold value.

S5: and if the detection signal gain difference value is larger than or equal to the set detection threshold value, determining that the first detection path in the metering pipeline has pollutants.

S6: and if the detection signal gain difference value is smaller than the set detection threshold value, determining that the first detection path in the metering pipeline is free of pollutants.

According to the method for detecting the pollutants in the metering pipeline, firstly, the fact that the current flow velocity in the metering pipeline of the flowmeter meets detection conditions is determined, the condition that the follow-up current detection signal gain value is influenced due to the fact that the current flow velocity is too large is eliminated, and misjudgment is prevented.

And then acquiring a current detection signal gain value of a detection piece on a first detection path in the metering pipeline, and determining a detection signal gain difference value according to the current detection signal gain value and the set detection signal gain value. If the detection signal gain difference value is greater than or equal to the set detection threshold value, the current detection signal gain exceeds the normal detection signal gain range, which indicates that the attenuation degree of the ultrasonic signal reaching the detection piece is serious, and proves that the ultrasonic signal is influenced by pollutants in the transmission process on the first detection path, and the attenuation degree of the ultrasonic signal is aggravated due to the existence of the pollutants, so that the pollutants on the first detection path in the metering pipeline are determined. If the detection signal gain difference value is smaller than the set detection threshold value, the current detection signal gain value is in a normal detection signal gain range, and the attenuation degree of the ultrasonic signal reaching the detection piece is in a normal range, so that the transmission of the ultrasonic signal on the first detection path is proved to be not influenced by pollutants, the attenuation degree of the ultrasonic signal is normal, and no pollutant on the first detection path in the metering pipeline is determined.

According to the embodiment of the application, the pollution condition inside the metering pipeline of the flowmeter can be detected in real time, the ideal flow field state in the metering pipeline is guaranteed, and the metering precision of the flowmeter is improved.

In one implementation, referring to fig. 3, the step of determining that the current flow rate in the metering conduit of the flowmeter meets the detection condition specifically includes:

s11: a current flow rate value within a metering conduit of the flow meter is obtained.

S12: and judging the magnitude relation between the current flow velocity value and the set flow velocity threshold value.

S13: if the current flow velocity value is larger than or equal to the set flow velocity threshold value, determining that the current flow velocity in the metering pipeline does not accord with the detection condition, and stopping detection.

S14: if the current flow velocity value is smaller than the set flow velocity threshold value, determining that the current flow velocity in the metering pipeline meets the detection condition.

It is worth noting that the detection of whether the current flow rate exceeds the set flow rate threshold is to determine that the current flow rate of the metering pipeline meets the test condition. For example, the set flow rate threshold may be set at 3m/s. If the current flow speed is greater than 3m/s, the intensity of the ultrasonic signal is greatly reduced in the transmission process, so that the gain value of the ultrasonic signal of the echo signal is increased, the error judgment that the gain difference value of the detection signal exceeds the set detection threshold value is easily caused, and the judgment that the pollutant exists in the metering pipeline is wrongly sent out. Therefore, the detection of the pollutants in the metering pipeline can be performed only at a small flow rate or no flow rate, and if the current flow rate is larger than the set flow rate threshold value, the detection of the pollutants in the metering pipeline is not suitable.

In one implementation, the set detection threshold includes a first set detection threshold and a second set detection threshold, the first set detection threshold being greater than the second set detection threshold.

For example, the first set detection threshold may be 15dB and the second set detection threshold may be 7dB. It can be understood that the gain difference of the ultrasonic signal is greater than or equal to the first set detection threshold, and compared with the gain difference of the ultrasonic signal which is between the second set detection threshold and the first set detection threshold, the attenuation degree of the ultrasonic signal is more serious, which means that the influence of pollutants on the transmission path of the ultrasonic signal is more serious and the pollution condition in the metering pipeline is more serious.

Referring to fig. 3, a relationship between a detected signal gain difference and a set detection threshold is determined, if the detected signal gain difference is greater than or equal to the set detection threshold, it is determined that there is a contaminant on a first detection path in the metering pipeline, and if the detected signal gain difference is less than the set detection threshold, it is determined that there is no contaminant on the first detection path in the metering pipeline, which specifically includes:

s41: and judging the magnitude relation between the detection signal gain difference value and the first set detection threshold value.

S42: if the difference value of the gain of the detection signal is larger than or equal to a first set detection threshold value, determining to send out a first pollution warning message, and stopping detection.

S43: if the detected signal gain difference is smaller than the first set detection threshold.

S44: and judging the magnitude relation between the detection signal gain difference value and the second set detection threshold value.

S45: and if the detection signal gain difference value is larger than or equal to a second set detection threshold value, determining to send out a second pollution warning message, and stopping detection.

S46: and if the detection signal gain difference value is smaller than the second set detection threshold value, determining that the first detection path in the metering pipeline is free of pollutants.

And setting a first set detection threshold and a second set detection threshold, and judging the set detection threshold of which the gain difference value of the detection signal is gradually reduced. First, the detected signal gain difference is compared with a first set detection threshold. When the difference value of the gain of the detection signals is larger than or equal to a first set detection threshold value, the fact that the attenuation of the ultrasonic signals is serious is indicated, the influence of pollutants in the metering pipeline is large, and first pollution warning information of serious pollution is sent out. And secondly, when the detection signal gain difference value is smaller than the first set detection threshold value, comparing the detection signal gain difference value with the second set detection threshold value. When the difference value of the gain of the detection signals is larger than or equal to a second set detection threshold value, the abnormal attenuation of the ultrasonic signals is indicated, the influence of pollutants in the metering pipeline is small, and a first pollution warning message of a pollution prompt is sent. Therefore, the pollution condition in the metering pipeline can be subjected to step-by-step risk prompt, and whether timely maintenance is needed or not can be judged conveniently according to the risk prompt.

In one implementation mode, at least two groups of first detection paths and at least two groups of second detection paths are arranged in the metering pipeline, the first detection paths and the second detection paths are not completely overlapped, and the second detection paths are not intersected with the inner wall of the metering pipeline; the detecting piece is positioned at the superposition part of the first detecting path and the second detecting path.

It is understood that the detection signal of the second detection path may also be an ultrasonic signal. The second detection path is not intersected with the metering pipeline, so that in the process of transmitting the ultrasonic signals along the second detection path, the ultrasonic signals are not contacted with the inner wall of the metering pipeline and are only transmitted in the fluid of the metering pipeline, and the transmission of the ultrasonic signals on the second detection path is not influenced by the pollutants on the inner wall of the metering pipeline.

Referring to fig. 3, after the step of determining that the current flow rate in the metering conduit of the flowmeter meets the detection condition, before obtaining the current detection signal gain value of the detection element located on the first detection path in the metering conduit, the method further includes:

s71: a current measured signal gain value of the sensing element located on the second sensing path is acquired.

It will be appreciated that when the ultrasonic signal is transmitted on the second detection path, the gain value of the ultrasonic signal on the detection member as the end of the transmission path is the current measurement signal gain value.

S72: and determining a measurement signal gain difference value according to the current measurement signal gain value and the set measurement signal gain value.

The setting of the gain value of the measurement signal may be an initial stage of the installation of the flowmeter, where no pollutant is in the metering pipeline, and the flow velocity of the fluid in the pipeline is smaller than the gain value of the ultrasonic signal of the detection element on the second detection path obtained under the condition that the set threshold value is smaller than the flow velocity of the fluid in the pipeline.

S73: and judging the magnitude relation between the gain difference value of the measurement signal and the set measurement threshold value.

S74: if the gain difference of the measuring signals is larger than or equal to the set measuring threshold value, determining that the detecting piece on the second detecting path in the metering pipeline has pollutants, sending out measuring pollution warning information, and stopping detection.

S75: if the measured signal gain difference is smaller than the set measurement threshold.

And S2, acquiring a current detection signal gain value of the detection piece on the first detection path in the metering pipeline.

It should be noted that, when the detecting member is located at the overlapping portion of the first detecting path and the second detecting path, the contaminant detection on the second detecting path may be performed first by a similar method as that of the contaminant detection on the first detecting path. Since the second detection path does not intersect the metering conduit, the measurement results are only directed to contaminant detection of the detection member itself, and do not involve contaminant detection of the inner wall of the metering conduit. And when the detection piece is determined to be free of pollutants, detecting the pollutants in the metering pipeline on the first detection path after the situation that the detection piece is free of the pollutants is eliminated. Because the detection piece is positioned at the superposition part of the first detection path and the second detection path, the detection result is only aimed at the first detection path, and the condition that the detection piece is polluted is eliminated, the precision of detecting the pollutant on the first detection path can be greatly improved. Especially when the first detection path contacts the inner wall of the metering tube, the contamination on the inner wall of the metering tube can be accurately detected.

FIG. 4 is a schematic structural diagram of a device for detecting contaminants in a metering pipeline according to an embodiment of the present disclosure; FIG. 5 is a cross-sectional view of the transducer of FIG. 4 in a radial cross-section near the inlet flange; fig. 6 is a cross-sectional view of the upper plane of fig. 5.

On the basis of the above embodiments, referring to fig. 4 to 6, in a second aspect, an embodiment of the present application provides a detection apparatus 100, where the detection apparatus 100 includes a first detection unit, an automatic gain control unit, a detection control unit, and an alarm control unit (each control unit is not shown) using the above detection method for measuring a contaminant inside a pipeline.

The first detecting unit is located on the first detecting path 131, and the first detecting unit includes a pair of first detecting pieces that are a detecting transmitting end and a detecting receiving end.

The first detection piece is electrically connected with the automatic gain control unit.

As shown in fig. 5, the inspection apparatus 100 includes a meter body 101, and an inlet flange 102 and an outlet flange 103 at both ends of the meter body 101. The meter body 101 has a measurement pipe 105 inside, and a first detection unit is provided on the measurement pipe 105. The first detection member of the first detection unit may comprise a transducer. The meter body 101 is connected with a control unit 104, and the control unit 104 comprises an automatic gain control unit, a detection control unit and an alarm control unit.

The ultrasonic signal is alternately transmitted downstream and upstream between a pair of first sensing elements. The ultrasonic signal attenuates during the transmission along the first detection path 131, and the automatic gain control unit is electrically connected to the first detection element, detects the attenuation degree of the echo signal on the first detection element as the detection receiving end, and amplifies the echo signal to a recognizable normal amplitude. The automatic gain control unit takes the multiple of the echo signal increase as a current detection signal gain value, and sends the current detection signal gain value to the detection control unit.

The detection control unit firstly determines a detection signal gain difference value according to the received current detection signal gain value and the set detection signal gain value. And then judging the magnitude relation between the detection signal gain difference value and the set detection threshold value. If the difference value of the detection signal gains is greater than or equal to the set detection threshold, it indicates that the current detection signal gain exceeds the normal detection signal gain range, which indicates that the attenuation degree of the ultrasonic signal reaching the detection piece is serious, and proves that the ultrasonic signal is affected by the pollutant in the transmission process on the first detection path 131, and the attenuation degree of the ultrasonic signal is aggravated due to the pollutant, so as to determine that the pollutant exists on the first detection path 131 in the metering pipeline. The detection control unit transmits information on the first detection path 131 having the contaminant to the alarm control unit, and the alarm control unit sends out warning information. If the detection signal gain difference is smaller than the set detection threshold, the current detection signal gain value is within the normal detection signal gain range, which indicates that the attenuation degree of the ultrasonic signal reaching the detection piece is within the normal range, and proves that the transmission of the ultrasonic signal on the first detection path 131 is not affected by pollutants, and the attenuation degree of the ultrasonic signal is normal, so that no pollutants are determined on the first detection path 131 in the metering pipeline. The optional detection control unit sends the information of no pollutant on the first detection path 131 to the alarm control unit, and the alarm control unit sends the information of normal detection result.

It is understood that the first detection unit may also perform measurement of the current flow velocity value according to a time difference between downstream transmission and upstream transmission of the ultrasonic signal, so as to determine whether the current flow velocity meets a measurement condition.

The detection device 100 provided by the embodiment of the application includes a first detection unit, an automatic gain control unit, a detection control unit and an alarm control unit, where the first detection unit is located on a first detection path 131, and the automatic gain control unit is electrically connected with a first detection element of the first detection unit and the detection control unit. The detection device uses the detection method of the internal pollutants of the metering pipeline to detect the internal pollutants of the metering pipeline of the flowmeter, can detect the pollution condition of the inside of the metering pipeline of the flowmeter in real time, ensures the ideal flow field state in the metering pipeline, and improves the metering precision of the flowmeter.

In one implementation, as shown with reference to fig. 5 and 6, the first detection path 131 intersects at least one of the inner walls of the metering tube 105.

The first detection path 131 intersects with the inner wall of the metering pipeline 105, so that the ultrasonic signal reaches the detection receiving end from the detection transmitting end along the first detection path 131 through the reflection at the intersection, and then the pollutant condition at the intersection of the ultrasonic signal and the inner wall of the metering pipeline 105 can be detected.

In some embodiments, the first detection path 131 may further intersect the inner wall of the metering tube 105 multiple times, so that the ultrasonic signal reaches the detection receiving end from the detection transmitting end through multiple reflections along the first detection path 131, and more pollution conditions of the inner wall of the metering tube 105 can be measured, and the efficiency is higher than that of single reflection.

In one possible embodiment, referring to fig. 5 and 6, the first detection path 131 is parallel to the axial direction of the metering tube 105.

The first detection path 131 is parallel to the axial direction of the metering tube 105, and the ultrasonic signal propagates in the axial plane, so that the contamination in the axial plane of the metering tube 105 can be detected. Correspondingly, when the first detection path 131 intersects the metering conduit 105 in this plane, a contamination condition at the intersection of the ultrasonic signal in this plane with the metering conduit 105 can be detected.

In some embodiments, the first detection path 131 may also optionally not transmit in an axial plane, such as a radial plane or any plane, where ultrasonic signals propagate, contamination of selected planes within the metering tube 105 may be detected. Correspondingly, when the first detection path 131 intersects the metering conduit 105 in the selected plane, a contamination condition at the intersection of the ultrasonic signal in the selected plane and the metering conduit 105 may be detected.

In one implementation, referring to fig. 5 and 6, the detection apparatus 100 further includes a second detection unit, where the second detection unit is located on the second detection path 132, and the second detection unit includes a pair of second detection elements that are a measurement transmitting end and a measurement receiving end, and the second detection elements are electrically connected to the automatic gain control unit.

The detection device 100 is provided with at least two first detection units and at least two second detection units, the first detection path 131 and the second detection path 132 not being completely coincident, the second detection path 132 not intersecting the inner wall of the metering conduit 105.

The first detecting member and the second detecting member are located at the overlapping portion of the first detecting path 131 and the second detecting path 132.

The second detection unit is additionally arranged to assist the first detection unit in detection. The second detection unit is located on the second detection path 132, and the second detection path 132 is not intersected with the metering pipeline, so that the transmission process of the ultrasonic signal along the second detection path 132 is only carried out in the fluid, and the ultrasonic signal is not influenced by pollutants on the inner wall of the metering pipeline.

The contaminant detection on the second detection path 132 is first performed using a similar method as the contaminant detection on the first detection path 131. Since the second detection path 132 does not intersect the metering conduit 105, the measurement results are only directed to contaminant detection of the second detection member itself, and do not involve contaminant detection of the metering conduit inner wall. When it is determined that the second detecting member itself is free of contaminants, the contaminant detection in the metering tube is performed on the first detecting path 131 after the condition that the second detecting member itself has contaminants is eliminated. Since the first detecting member and the second detecting member are located at the overlapping portion of the first detecting path 131 and the second detecting path 132, the detection result is only for the first detecting path 131, and the first detecting member itself is already excluded from being contaminated, the accuracy of detecting the contaminant on the first detecting path 131 can be improved greatly. Especially when the first detection path contacts the inner wall of the metering tube 105, a contamination on the inner wall of the metering tube 105 can be accurately detected.

It can be understood that when the flowmeter is an ultrasonic flowmeter, the second detection unit can be a transducer on the original measurement path in the ultrasonic flowmeter, and only the first detection unit is needed to be additionally arranged at a reasonable position, so that the second detection unit can be used for auxiliary detection. Accordingly, a measurement of the current flow rate may also be made with the second detection unit.

In one possible embodiment, a detection combination of two second detection units and two first detection units is provided, the two second detection units and the two first detection units of the same detection combination being located in the same detection plane.

One detection assembly is provided, the detection plane of which passes through the central axis of the metering tube 105.

Alternatively, a plurality of detection combinations are provided. Wherein the detection planes of the plurality of detection combinations are parallel to each other and to the central axis of the metering tube 105, or the detection planes of the plurality of detection combinations intersect.

The two second detection units and the two first detection units of the same detection combination are all located in the same plane, so that the design of the first detection path 131 and the second detection path 132 is convenient to realize, and the structure is more compact. A detection assembly detection plane passes through the central axis of the metering conduit 105 for ease of installation and to measure the presence or absence of a build-up of contaminants on the detection path of the detection plane.

In some embodiments, multiple sets of detection combinations may also be provided to form multiple different detection planes. The plurality of detection planes can be arranged in parallel or in an intersecting manner, and the plurality of detection planes can be arranged to detect more positions of the metering pipeline 105 and judge whether the pollutants are accumulated at the more positions, so that the measuring result of the flowmeter is more accurate.

As shown in fig. 5 and 6, the fluid in the metering conduit 105 flows in the direction indicated by the open arrows. The detection device 100 is provided with two sets of detection combinations. The detection planes of the two detection combinations are parallel to each other and to the central axis of the metering tube 105. The two detection planes correspond to the upper plane 110 and the lower plane 120, respectively. Wherein the arrangement of the first and second detection units in the upper plane 110 and in the lower plane 120 is exactly the same and the orthographic projections in the planes of each other coincide with each other. Taking one plane as an example for illustration, the structure of the upper plane 110 shown in fig. 6 is schematically illustrated, wherein the reference numerals in brackets are the reference numerals of the corresponding components in the lower plane 120, and fig. 5 is a schematic view of the radial cross section of the detecting element near the inlet flange 102 in fig. 6; wherein the reference numerals located in brackets are the reference numerals of corresponding parts in the radial section near the outlet flange 103.

Four transducers, namely a first transducer 111, a second transducer 112, a third transducer 113 and a fourth transducer 114, are arranged in the upper plane 110. The four transducers are distributed in a rectangular shape, and the signal receiving and transmitting ends of the four transducers point to the center of the rectangle.

Wherein the second transducer 112 and the fourth transducer 114 form a first detection unit, and the ultrasonic signal is reflected at opposite sides of the second transducer 112 and the fourth transducer 114 to form a first detection path 131 in fig. 6. The first transducer 111 and the second transducer 112 form a second detection unit, and the ultrasonic signal is transmitted straight between the first transducer 111 and the second transducer 112 to form a second detection path 132 in fig. 6. The second detection path 132 does not intersect the inner wall of the measuring pipe 110, and the first detection path 131 intersects the inner wall of the measuring pipe 110. As can be seen from the above, the first detection path 131 and the second detection path 132 overlap at the second transducer 112, and the second transducer 112 is located on the overlapping portion of the first detection path 131 and the second detection path 132.

For the sake of distinction, the first detection unit of the other group is referred to as a third detection unit, the corresponding detection path is referred to as a third detection path 133, the second detection unit of the other group is referred to as a fourth detection unit, and the corresponding detection path is referred to as a fourth detection path 134. The first transducer 111 and the third transducer 113 form a third detection unit and the ultrasonic signal is reflected at opposite sides of the first transducer 111 and the third transducer 113 forming a third detection path 133 in fig. 6. The third transducer 113 and the fourth transducer 114 form a fourth detection unit, and the ultrasonic signal is transmitted straight between the third transducer 113 and the fourth transducer 114 to form a fourth detection path 134 in fig. 6. The fourth detection path 134 does not intersect the inner wall of the measuring pipe 110, and the third detection path 133 intersects the inner wall of the measuring pipe 110. As can be seen from the above, the third detection path 133 and the fourth detection path 134 overlap at the third transducer 113, and the third transducer 113 is located at the overlapping portion of the third detection path 133 and the fourth detection path 134.

Meanwhile, the first transducer 111 is located at the overlapping portion of the third detection path 133 and the second detection path 132, and the fourth transducer 114 is located at the overlapping portion of the first detection path 131 and the fourth detection path 134.

It can be seen that any of the first transducer 111, the second transducer 112, the third transducer 113, and the fourth transducer 114 can be located at the overlapping portion of one of the first detection paths 131 and one of the second detection paths 132.

The transducers are disposed in the lower plane 120 in the same arrangement to form a first detection unit and a second detection unit. For the sake of distinction, the transducers of the lower plane are referred to as fifth transducer 125, sixth transducer 126, seventh transducer 127, and eighth transducer 128, respectively, forming fifth detection path 145, sixth detection path 146, seventh detection path 147, and eighth detection path 148 shown in fig. 6. Similarly, any of the fifth transducer 125, sixth transducer 126, seventh transducer 127, and eighth transducer 128 described above may be located at the coincident portion of one of the sets of first detection paths 131 and one of the sets of second detection paths 132.

In summary, the transducers are all located at the overlapping portion of the first detection path 131 and the second detection path 132, so that the detection accuracy of the contaminant on the first detection path 131 can be improved by using a two-time detection method.

It should be noted that, since the transducers may be located on the second detection path 132, the transducers on the measurement path of the original ultrasonic flowmeter may be used, and a detection control unit and an alarm control unit may be added to form the detection device 100. The original ultrasonic flowmeter is directly used, the transducer is not required to be additionally arranged, the cost and the space for additional arrangement are not required to be increased, the cost is reduced, and the structure is compact; and the first detection path 131 and the second detection path 132 can be formed, and the second detection path 132 is utilized to detect the pollutant of the second detection member, so that the detection precision is improved.

In the present embodiment, both the upper and lower planar surfaces 110, 120 are spaced from the central axis of the metering tube 105 so that contamination in both detection planes can be detected. The vertical distance d between the upper plane and the lower plane to the central axis is equal, and the second sensing units of the upper plane 110 and the lower plane 120 may also have a mutual calibration effect in measuring the current flow rate.

On the basis of the above embodiments, in a third aspect, an embodiment of the present application provides a flow meter, including the detection device 100 described above.

The detection device 100 uses the detection method of the pollutants in the metering pipeline, and comprises a first detection unit, an automatic gain control unit, a detection control unit and an alarm control unit, wherein the first detection unit is positioned on a first detection path 131, and the automatic gain control unit is electrically connected with a first detection piece and the detection control unit of the first detection unit. Other technical features of the detection device 100 are the same as those described above, and have the same beneficial effects, and will not be described again.

The flowmeter provided by the embodiment of the application can detect the pollution condition inside the metering pipeline of the flowmeter in real time, ensure the ideal flow field state in the metering pipeline and improve the metering precision of the flowmeter.

In the description of the embodiments of the present application, it should be noted that, unless explicitly specified and limited otherwise, the terms "mounted," "connected," and "connected" are to be construed broadly, and may be fixedly connected, or indirectly connected through intermediaries, for example, or may be in communication with each other between two elements or in an interaction relationship between the two elements. The specific meaning of the terms in this application will be understood by those of ordinary skill in the art as the case may be.

In the description of the embodiments of the present application, it should be understood that the terms "upper," "lower," "front," "rear," "vertical," "horizontal," "top," "bottom," "inner," "outer," and the like indicate an orientation or a positional relationship based on that shown in the drawings, merely for convenience of description and to simplify the description, and do not indicate or imply that the devices or elements referred to must have a specific orientation, be configured and operated in a specific orientation, and thus should not be construed as limiting the present application. In the description of the present application, the meaning of "a plurality" is two or more, unless specifically stated otherwise.

The terms "first," "second," "third," "fourth" and the like in the description and in the claims of this application and in the above-described figures, if any, are used for distinguishing between similar objects and not necessarily for describing a particular sequential or chronological order. It is to be understood that the data so used may be interchanged where appropriate such that embodiments of the present application described herein may be implemented in sequences other than those illustrated or otherwise described herein. Furthermore, the terms "comprises," "comprising," and "having," and any variations thereof, are intended to cover a non-exclusive inclusion, such that a process, method, system, article, or apparatus that comprises a list of steps or elements is not necessarily limited to those steps or elements expressly listed but may include other steps or elements not expressly listed or inherent to such process, method, article, or apparatus.

Finally, it should be noted that: the above embodiments are only for illustrating the technical solution of the present application, and not for limiting the same; although the present application has been described in detail with reference to the foregoing embodiments, it should be understood by those of ordinary skill in the art that: the technical scheme described in the foregoing embodiments can be modified or some or all of the technical features thereof can be replaced by equivalents; such modifications and substitutions do not depart from the spirit of the corresponding technical solutions from the scope of the technical solutions of the embodiments of the present application.

Claims

1. A method for detecting a contaminant inside a metering pipeline, which is applied to a flowmeter, the method for detecting the contaminant inside the metering pipeline comprises the following steps:

2. The method of claim 1, wherein the step of determining that the current flow rate in the metering conduit of the flowmeter meets the detection condition comprises:

3. The method of claim 1, wherein the set detection threshold comprises a first set detection threshold and a second set detection threshold, the first set detection threshold being greater than the second set detection threshold;

4. A method of detecting a contaminant within a metering conduit according to any one of claims 1 to 3, wherein at least two sets of said first detection paths and at least two sets of second detection paths are provided within said metering conduit, said first detection paths and said second detection paths not being fully coincident, said second detection paths not intersecting an interior wall of said metering conduit;

5. A detection device, characterized in that the detection method of the internal pollutant of the metering pipeline according to any one of the preceding claims 1 to 4 is used, and the detection device comprises a first detection unit, an automatic gain control unit, a detection control unit and an alarm control unit;

6. The test device of claim 5, wherein the first test path intersects at least one of the inner walls of the metering conduit.

7. The test device of claim 5, wherein the first test path is parallel to an axial direction of the metering tube.

8. The apparatus according to any one of claims 5 to 7, further comprising a second detection unit located on a second detection path, the second detection unit including a pair of second detection pieces that are a measurement transmitting end and a measurement receiving end each other, the second detection pieces being electrically connected to the automatic gain control unit;

9. The detecting device according to claim 8, wherein two second detecting units and two first detecting units are provided to form one detecting combination, and two second detecting units and two first detecting units of one detecting combination are located in the same detecting plane;

10. A flowmeter comprising the detection device of any of claims 5-9.