CN110657854A - Device and method for automatically eliminating dead lock of volumetric flowmeter - Google Patents

Device and method for automatically eliminating dead lock of volumetric flowmeter Download PDF

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Publication number
CN110657854A
CN110657854A CN201911014020.3A CN201911014020A CN110657854A CN 110657854 A CN110657854 A CN 110657854A CN 201911014020 A CN201911014020 A CN 201911014020A CN 110657854 A CN110657854 A CN 110657854A
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flowmeter
medium
reversing
pressure
dead
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CN110657854B (en
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袁伯利
邓卫东
胡绪山
向德辉
王国财
吴志刚
何辰星
张国涛
张超
向汉东
赖文明
刘万涛
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Jingzhou Mind Science & Technology Co Ltd
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Jingzhou Mind Science & Technology Co Ltd
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    • GPHYSICS
    • G01MEASURING; TESTING
    • G01FMEASURING VOLUME, VOLUME FLOW, MASS FLOW OR LIQUID LEVEL; METERING BY VOLUME
    • G01F15/00Details of, or accessories for, apparatus of groups G01F1/00 - G01F13/00 insofar as such details or appliances are not adapted to particular types of such apparatus
    • G01F15/10Preventing damage by freezing or excess pressure or insufficient pressure

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  • Physics & Mathematics (AREA)
  • Fluid Mechanics (AREA)
  • General Physics & Mathematics (AREA)
  • Measuring Volume Flow (AREA)

Abstract

The invention discloses a device and a method for automatically eliminating dead lock of a volumetric flowmeter, wherein the device comprises: the system comprises two three-way valves with actuators, a reversing controller and two pressure transmitters; the common channels of the two three-way valves are respectively connected with two ends of the flowmeter, and pressure transmitters are arranged between the common channels of the three-way valves and the flowmeter; the pressure transmitter and the actuator are electrically connected with the reversing controller; two medium reversing ends of each three-way valve are respectively connected with a medium input port and a medium output port. The device and the method for automatically eliminating the dead blockage of the volumetric flowmeter can automatically judge whether the flowmeter is dead, can switch the direction of a medium flowing into the flowmeter after the flowmeter is dead, push the flowmeter to reverse by using the pressure difference of the medium, eliminate the dead blockage fault and continue normal metering, greatly reduce the maintenance and maintenance frequency of the flowmeter, reduce the use cost and ensure that the flowmeter can normally work in the field of crude oil gathering and transportation.

Description

Device and method for automatically eliminating dead lock of volumetric flowmeter
Technical Field
The invention relates to the technical field of flowmeter application, in particular to a device and a method for automatically eliminating dead lock of a volumetric flowmeter.
Background
The positive displacement flowmeter is a flow metering instrument with high precision, small pressure loss, long service life and convenient installation and use, and is widely applied to the field of accurate metering of clean fluid. For a long time, engineers have wanted to convert rotary positive displacement meters, such as: a waist wheel flowmeter, a scraper type flowmeter or a dual-rotor flowmeter is used in the field of crude oil gathering and transportation, but because crude oil contains a large amount of fine silt with different particle sizes and different forms, the rotors of the precision flowmeters cannot be filtered, the rotors of the precision flowmeters are blocked and shut down, the volumetric flowmeter is complex in structure, certain special skills are needed for field maintenance, and time is consumed, so that the application of the volumetric flowmeter in the field is seriously influenced.
Therefore, how to automatically eliminate the card death when the card death occurs is a problem that needs to be solved by those skilled in the art.
Disclosure of Invention
In view of the above, the present invention provides a device and a method for automatically eliminating the dead lock of a volumetric flowmeter, which can automatically determine whether the flowmeter is dead and automatically eliminate the dead lock.
In order to achieve the purpose, the invention adopts the following technical scheme:
an apparatus for automatically eliminating volumetric flow meter seizing, comprising: the system comprises two three-way valves with actuators, a reversing controller and two pressure transmitters;
the common channels of the two three-way valves are respectively connected with two ends of the flowmeter, and the pressure transmitters are arranged between the common channels of the three-way valves and the flowmeter; the pressure transmitter and the actuator are both electrically connected with the reversing controller;
and two medium reversing ends of each three-way valve are respectively connected with a medium input port and a medium output port.
Preferably, the common passage of each of the three-way valves is connected to the flow meter through a connecting pipe and a flow meter connecting terminal. The connecting terminal facilitates mounting and dismounting of the flowmeter.
The three-way valve is provided with an actuator controlled by a reversing controller and can automatically reverse.
Preferably, the three-way valve is a two-way three-way reversing valve, i.e. the three-way valve can ensure that the inlet channel (common channel) is communicated with one of the outlet channels, and the medium flow direction is not limited, so that the medium can flow into the inlet channel (common channel) from the inlet channel (common channel) or the outlet channel from the outlet channel.
Preferably, the two pressure transmitters are respectively used for measuring the medium pressure at two ends of the flowmeter and transmitting the medium pressure to the reversing controller.
Preferably, the reversing controller senses whether the flowmeter is stuck based on whether a medium pressure difference value at two ends of the flowmeter exceeds a set value, and if the flowmeter is stuck, the reversing controller sends a reversing signal to the actuator to switch the medium flow direction of the flowmeter.
Preferably, the reversing controller is a separate device or the reversing controller and the flow meter are integrated. Namely, the reversing controller can be used as a functional component independently, and can also be integrated with the metering function of the flow meter, namely, the flow meter is provided with the reversing controller. In practical implementation, an integrated flow meter can be adopted, or a split mode of the reversing controller and the flow meter can be adopted, and the flow meter can be specifically selected according to conditions.
A method of automatically eliminating volumetric flow meter seizing, comprising:
s1, when the device starts to work, the reversing controller controls a three-way valve close to a conveying medium inlet to be communicated with a medium inlet pipeline in a default mode, a three-way valve close to a conveying medium outlet to be communicated with a medium outlet pipeline, the flow meter rotates in the forward direction for metering, the device is in the most energy-saving conveying state, meanwhile, the reversing controller judges whether the pressure difference between the inlet and the outlet of the flow meter, measured by the pressure transmitter, is smaller than a set value or not, if the pressure difference between the inlet and the outlet is larger than the set value, the time is delayed for several seconds, if the condition is still met, the flow meter is judged;
in a specific implementation, the time of the delay wait may be determined according to a specific experiment, for example: and may be 30 seconds.
S2: the reversing controller controls a three-way valve close to a conveying medium inlet to be communicated with a medium outlet pipeline, the three-way valve close to the conveying medium outlet is communicated with the medium inlet pipeline, the flowmeter rotates reversely to measure, meanwhile, the reversing controller judges whether the pressure difference between the inlet and the outlet of the flowmeter measured by the pressure transmitter is smaller than a set value or not, if the pressure difference is larger than the set value, the time delay is waited for a plurality of seconds, if the condition is still, the flowmeter is judged to be blocked reversely, the step S1 is carried out, a period of time is delayed for waiting for whether the pressure difference is normal or not, if the pressure difference is abnormal, the forward direction is;
in a specific implementation, the time of the delay wait may be determined according to a specific experiment, for example: and may be 30 seconds.
And S3, the reversing controller stops reversing, gives out a fault alarm, continuously monitors the pressure difference between the inlet and the outlet of the flowmeter, and if the pressure difference is recovered to be normal, the fault alarm is eliminated.
The term "normal recovery" as used herein means that the pressure difference is within a set value range, such as: when the fault is processed, the transfusion is stopped in front, or after the time is longer than the delay time, the flow meter slowly and successfully removes the blockage.
According to the technical scheme, compared with the prior art, the device and the method for automatically eliminating the dead blockage of the volumetric flowmeter can automatically judge whether the flowmeter is dead or not, the direction of a medium flowing into the flowmeter can be switched through the three-way valve after the flowmeter is dead, the dead blockage fault can be automatically eliminated through the reversing pressure difference pushing of the medium, and the metering error caused by the dead blockage fault can be ignored, so that the maintenance frequency and the fault production stop probability of the flowmeter are greatly reduced, the use cost is reduced, and the volumetric flowmeter is applied to the field of crude oil gathering and transportation.
Drawings
In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the drawings used in the description of the embodiments or the prior art will be briefly described below, it is obvious that the drawings in the following description are only embodiments of the present invention, and for those skilled in the art, other drawings can be obtained according to the provided drawings without creative efforts.
FIG. 1 is a schematic structural diagram of an apparatus for automatically eliminating the dead lock of a volumetric flowmeter according to the present invention;
FIG. 2 is a schematic structural diagram of another apparatus for automatically eliminating the dead lock of a positive displacement flowmeter according to the present invention;
FIG. 3 is a schematic view of the media flow provided by the present invention.
Reference numerals:
1. a connection terminal; 2. a three-way valve; 3. an actuator; 4. a pressure transmitter; 5. a commutation controller; 6. and connecting the pipelines.
Detailed Description
The technical solutions in the embodiments of the present invention will be clearly and completely described below with reference to the drawings in the embodiments of the present invention, and it is obvious that the described embodiments are only a part of the embodiments of the present invention, and not all of the embodiments. All other embodiments, which can be derived by a person skilled in the art from the embodiments given herein without making any creative effort, shall fall within the protection scope of the present invention.
The invention provides a device and a method for automatically identifying and eliminating the dead jam of a volumetric flowmeter, aiming at the phenomenon that the rotary volumetric flowmeter is easy to jam, and the device and the method are as follows:
referring to fig. 1, an embodiment of the present invention discloses an apparatus for automatically eliminating a dead lock of a volumetric flowmeter, including: two three-way valves 2 with actuators 3, a reversing controller 5 and two pressure transmitters 4;
the common channels of the two three-way valves 2 are respectively connected with two ends of the flowmeter, and pressure transmitters 4 are arranged between the common channels of the three-way valves 2 and the flowmeter; the pressure transmitter 4 and the actuator 3 are both electrically connected with the reversing controller 5;
two medium reversing ends of each three-way valve 2 are respectively connected with a medium input port and a medium output port.
Preferably, the common channel of each three-way valve 2 is connected to the flow meter via a connecting line 6 and a flow meter connecting terminal 1.
As shown in fig. 1, the connection terminal 1 is used to facilitate mounting and dismounting of the flowmeter, and is preferably, but not limited to, a flange connection, as long as it is mated with the flowmeter connection terminal.
The three-way valve 2 has A, B two, preferably but not limited to three-way ball valve type reversing valves, each three-way valve has a, b and c channels, wherein a is an inlet channel, namely a common channel, and is provided with an on-off type actuator 3. The actuator 3 can communicate a with b or a with c, and the channel a is connected with the flow meter connecting terminal 1, the channels b and c are connected with the inlet of the conveying medium, and the other channel is connected with the outlet of the conveying medium. The actuator 3 is preferably but not limited to an electric actuator, and the actuator 3 rotates forwards or backwards by 90 degrees, so that the communication between the channel a and the channel b of the three-way valve 2 can be switched to the communication between the channel a and the channel c, or vice versa. The pressure transmitters 4 are respectively arranged on the connecting pipelines of the two ports of the flowmeter and used for testing the medium pressure of the two ports.
When the reversing controller 5 is electrified to work, the valve A in the three-way valve 2 can be communicated with a medium inlet of the device, the valve B is communicated with a medium outlet, and the flowmeter rotates in the positive direction for metering, so that the conveying is most energy-saving due to the fact that the pipeline is short and the number of passing elbows is small; when the flowmeter is clamped in the forward direction, the differential pressure value of the two pressure transmitters 4 rises and continuously exceeds a set value, the reversing controller 5 judges that the flowmeter is clamped in the forward direction, so that the control actuator 3 is switched into the state that the valve B is communicated with the medium inlet of the device, the valve A is communicated with the medium outlet of the device, the flowmeter rotates in the reverse direction under the pushing of differential pressure, the clamped position of sand grains and the rotor is separated, the flowmeter continues to measure, and the differential pressure is recovered to be normal; similarly, when the flowmeter is blocked reversely, the forward rotation metering is switched to.
In addition, referring to fig. 2, another device for automatically eliminating the dead lock of the volumetric flowmeter is disclosed in the embodiment of the present invention, and the difference between the embodiment and the device provided in the previous embodiment is only that the aforementioned reversing controller 5 is not used as a single functional component, but the function thereof is integrated with the flowmeter metering function, so that the flowmeter determines the dead lock by itself, and the three-way valve 2 is controlled to reverse to eliminate the dead lock. This is a preferred embodiment, which can reduce costs and optimize the device, but only requires secondary development of the flow totalizer.
The method for automatically eliminating the dead lock of the volumetric flowmeter provided by the invention is described below with reference to fig. 3, and specifically includes the following steps:
1. when the reversing controller normally starts to work, the reversing controller controls the three-way valve A to be communicated with the medium inlet pipeline in a default mode, namely, the channel a is communicated with the channel B, the three-way valve B is communicated with the medium outlet pipeline, namely, the channel a is communicated with the channel B, the medium flows to the medium inlet → the three-way valve A (B → a) → flow meter → the three-way valve B (a → B) → medium outlet, as shown by a solid arrow in FIG. 2, the flow meter rotates in the forward direction for metering, and meanwhile, the reversing controller monitors that the differential pressure between the pressure transmitter P1 and the pressure transmitter P2 is smaller than a set value (for example, 200 KP.
2. When the flowmeter is jammed in the forward direction, the differential pressure between the pressure transmitter P1 and the pressure transmitter P2 exceeds a set value, the reversing controller controls the three-way valve B to be communicated with the medium inlet pipeline, namely the channel c is communicated with the channel a, the three-way valve A is communicated with the medium outlet pipeline, namely the channel a is communicated with the channel c, the medium flows to the medium inlet → the three-way valve B (c → a) → flowmeter → the three-way valve A (a → c) → medium outlet, and the flowmeter reversely rotates for metering as shown by a dotted arrow in FIG. 2.
3. When the reverse metering is blocked, the pressure difference between the pressure transmitter P2 and the pressure transmitter P1 exceeds a set value, and in this situation, the reversing controller judges that the flowmeter is blocked reversely, and then the reverse metering is converted into the forward metering in the step 1, and the steps are repeated.
In addition, it should be noted that the device and method for eliminating the dead lock of the volumetric flowmeter provided by the invention are suitable for volumetric flowmeters which allow forward and reverse rotation and continuously meter, such as: intelligent roots flowmeter, intelligent scraper flowmeter and intelligent birotor flowmeter.
The device and the method for eliminating the dead blockage of the volumetric flowmeter can automatically judge whether the flowmeter is dead, can switch the direction of a medium flowing into the flowmeter after the flowmeter is dead, push the flowmeter to reverse by using the pressure difference of the medium, eliminate the dead blockage fault and continue normal metering, greatly reduce the maintenance and maintenance frequency of the flowmeter, reduce the use cost and ensure that the flowmeter can normally work in the field of crude oil gathering and transportation.
The embodiments in the present description are described in a progressive manner, each embodiment focuses on differences from other embodiments, and the same and similar parts among the embodiments are referred to each other. The device disclosed by the embodiment corresponds to the method disclosed by the embodiment, so that the description is simple, and the relevant points can be referred to the method part for description.
The previous description of the disclosed embodiments is provided to enable any person skilled in the art to make or use the present invention. Various modifications to these embodiments will be readily apparent to those skilled in the art, and the generic principles defined herein may be applied to other embodiments without departing from the spirit or scope of the invention. Thus, the present invention is not intended to be limited to the embodiments shown herein but is to be accorded the widest scope consistent with the principles and novel features disclosed herein.

Claims (7)

1. An automatic get rid of dead device of volumetric flowmeter card, its characterized in that includes: the system comprises two three-way valves with actuators, a reversing controller and two pressure transmitters;
the common channels of the two three-way valves are respectively connected with two ends of the flowmeter, and the pressure transmitters are arranged between the common channels of the three-way valves and the flowmeter; the pressure transmitter and the actuator are both electrically connected with the reversing controller;
and two medium reversing ends of each three-way valve are respectively connected with a medium input port and a medium output port.
2. An apparatus for automatically eliminating volumetric flow meter seizing according to claim 1, wherein the common passage of each of said three-way valves is connected to said flow meter by a connecting conduit and a flow meter connecting terminal.
3. The apparatus of claim 1, wherein the three-way valve is a two-way three-way reversing valve.
4. The apparatus of claim 1, wherein the diverter controller is a separate device or the diverter controller and the flow meter are an integrated device.
5. The device for automatically eliminating the dead lock of the volumetric flowmeter as claimed in any one of claims 1-4, wherein two pressure transmitters are respectively used for measuring the medium pressure at two ends of the flowmeter and transmitting the medium pressure to the reversing controller.
6. The device for automatically eliminating the dead lock of the volumetric flowmeter according to claim 5, wherein the reversing controller senses whether the flowmeter is dead based on whether a pressure difference value of media at two ends of the flowmeter exceeds a set value, and if the flowmeter is dead, a reversing signal is sent to the actuator to switch the flow direction of the media of the flowmeter.
7. A method of automatically eliminating volumetric flow meter seizing, comprising:
s1, when the device starts to work, the reversing controller controls a three-way valve close to a conveying medium inlet to be communicated with a medium inlet pipeline in a default mode, a three-way valve close to a conveying medium outlet to be communicated with a medium outlet pipeline, the flow meter rotates in the forward direction for metering, the device is in the most energy-saving conveying state, meanwhile, the reversing controller judges whether the pressure difference between the inlet and the outlet of the flow meter, measured by the pressure transmitter, is smaller than a set value or not, if the pressure difference between the inlet and the outlet is larger than the set value, the time is delayed for several seconds, if the condition is still met, the flow meter is judged;
s2: the reversing controller controls a three-way valve close to a conveying medium inlet to be communicated with a medium outlet pipeline, the three-way valve close to the conveying medium outlet is communicated with the medium inlet pipeline, the flowmeter rotates reversely to measure, meanwhile, the reversing controller judges whether the pressure difference between the inlet and the outlet of the flowmeter measured by the pressure transmitter is smaller than a set value or not, if the pressure difference is larger than the set value, the time delay is waited for a plurality of seconds, if the condition is still, the flowmeter is judged to be blocked reversely, the step S1 is carried out, a period of time is delayed for waiting for whether the pressure difference is normal or not, if the pressure difference is abnormal, the forward direction is;
and S3, the reversing controller stops reversing, gives out a fault alarm, continuously monitors the pressure difference between the inlet and the outlet of the flowmeter, and if the pressure difference is recovered to be normal, the fault alarm is eliminated.
CN201911014020.3A 2019-10-23 2019-10-23 Device and method for automatically removing blocking of positive displacement flowmeter Active CN110657854B (en)

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CN110657854B CN110657854B (en) 2024-06-25

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Citations (8)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN201396139Y (en) * 2009-05-21 2010-02-03 中国石油天然气股份有限公司 Cluster well automatic well-selecting on-line metering device
CN201561772U (en) * 2009-12-11 2010-08-25 冯磊 Self-cleaning type gas flow device
CN202104775U (en) * 2011-05-31 2012-01-11 九阳股份有限公司 Quantitative soya-bean milk making device
CN204960918U (en) * 2015-08-07 2016-01-13 山东正辉石油装备集团有限公司 Multi -well type oil gas metering device
CN205477586U (en) * 2016-03-29 2016-08-17 中国石油化工股份有限公司 Tubular oil well two -phase flow gauge
CN107246259A (en) * 2016-03-29 2017-10-13 中国石油化工股份有限公司 Tubular type oil well gas-liquid two-phase flow meter and its measuring method
CN208902204U (en) * 2018-11-05 2019-05-24 湖北三宁化工股份有限公司 A kind of differential pressure type gas flowmeter automatic blowout device
CN208921648U (en) * 2018-09-30 2019-05-31 郑州忠林智能科技有限公司 The electronic type oil-water ratio testing agency at volumetric metering station

Patent Citations (8)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN201396139Y (en) * 2009-05-21 2010-02-03 中国石油天然气股份有限公司 Cluster well automatic well-selecting on-line metering device
CN201561772U (en) * 2009-12-11 2010-08-25 冯磊 Self-cleaning type gas flow device
CN202104775U (en) * 2011-05-31 2012-01-11 九阳股份有限公司 Quantitative soya-bean milk making device
CN204960918U (en) * 2015-08-07 2016-01-13 山东正辉石油装备集团有限公司 Multi -well type oil gas metering device
CN205477586U (en) * 2016-03-29 2016-08-17 中国石油化工股份有限公司 Tubular oil well two -phase flow gauge
CN107246259A (en) * 2016-03-29 2017-10-13 中国石油化工股份有限公司 Tubular type oil well gas-liquid two-phase flow meter and its measuring method
CN208921648U (en) * 2018-09-30 2019-05-31 郑州忠林智能科技有限公司 The electronic type oil-water ratio testing agency at volumetric metering station
CN208902204U (en) * 2018-11-05 2019-05-24 湖北三宁化工股份有限公司 A kind of differential pressure type gas flowmeter automatic blowout device

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