CN113483946B - Water filling and exhausting system and method for differential pressure transmitter - Google Patents
Water filling and exhausting system and method for differential pressure transmitter Download PDFInfo
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- CN113483946B CN113483946B CN202110608048.0A CN202110608048A CN113483946B CN 113483946 B CN113483946 B CN 113483946B CN 202110608048 A CN202110608048 A CN 202110608048A CN 113483946 B CN113483946 B CN 113483946B
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- G—PHYSICS
- G01—MEASURING; TESTING
- G01L—MEASURING FORCE, STRESS, TORQUE, WORK, MECHANICAL POWER, MECHANICAL EFFICIENCY, OR FLUID PRESSURE
- G01L27/00—Testing or calibrating of apparatus for measuring fluid pressure
- G01L27/007—Malfunction diagnosis, i.e. diagnosing a sensor defect
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Abstract
The invention discloses a water filling and exhausting system of a differential pressure transmitter, which comprises: a system pipeline, wherein a load cell is arranged in the system pipeline; the front end of the load cell is connected to the positive pressure side of the differential pressure transmitter through the instrument pipeline and the primary isolation valve and the secondary isolation valve of the positive pressure side, which are arranged on the instrument pipeline, in sequence, the rear end of the load cell is connected to the negative pressure side of the differential pressure transmitter through the instrument pipeline and the primary isolation valve and the secondary isolation valve of the negative pressure side, which are arranged on the instrument pipeline, in sequence, and a balance valve is connected between the instrument pipeline, which is close to one side of the differential pressure transmitter, of the secondary isolation valve of the positive pressure side and the instrument pipeline, which is close to one side of the differential pressure transmitter, of the secondary isolation valve of the negative pressure side; the differential pressure transmitter is positioned below the positive pressure measurement secondary isolation valve and the negative pressure side secondary isolation valve. In addition, the invention also discloses an online full-automatic water filling and exhausting method of the differential pressure transmitter.
Description
Technical Field
The invention belongs to the technical field of differential pressure transmitters, and particularly relates to a water filling and exhausting system and method of a differential pressure transmitter.
Background
Currently, differential pressure transmitters are widely used in the field to measure industrial field fluid level, flow and pressure parameters. In the application process, the differential pressure transmitter generally has more fluctuation phenomenon due to the air in the instrument pipeline. In order to avoid fluctuation, water filling and air exhausting work is needed to be carried out on the instrument in the overhauling process.
In the prior art, the normal water filling and exhausting flow is as follows: under the condition that the system does not operate, the secondary isolation valve is opened, a plug on a plug seat of the differential pressure transmitter is opened, a medium in the system is utilized to discharge a plug hole, air in an instrument pipeline is taken out, after no bubble in the plug hole is confirmed, the secondary isolation valve is closed, the plug opening is screwed, and water filling and air exhausting work is completed.
However, the water-filled venting process of the prior art has the following problems:
1) In the water-filled venting process, a large volume of medium must be vented in order to completely purge the meter line of air. However, the discharge of a large amount of medium brings the risk of contamination to personnel, equipment and the environment, a large amount of overhaul waste is generated, and a large amount of protection work is needed in the overhaul process to ensure the safety of the personnel, the equipment and the environment, so that the overhaul work is increased and the overhaul time is longer.
2) The water filling and exhausting work needs to be carried out by referring to a system medium, when the water filling and exhausting work is carried out, the high-temperature and high-pressure medium is sprayed out, so that great risks are brought to maintenance personnel, and the risk of cracking is possibly brought to the system, therefore, the online water filling and exhausting work is difficult to carry out, the risk is extremely high, and the online water filling and exhausting work is difficult to carry out under the general condition.
3) The irradiation risk of part of places is extremely high, and when the water filling and exhausting work is performed in daily operation, the water filling and exhausting work of part of meters is not sufficiently performed when overhauling, so that the fluctuation phenomenon generated by the meters is difficult to solve and treat in time, and the risk is brought to a unit.
In view of the foregoing, it is desirable to provide a water-filled differential pressure transmitter exhaust system and method that avoids leakage of medium within the system lines.
Disclosure of Invention
The invention aims at: a water-filled exhaust system and method for a differential pressure transmitter is provided that can avoid leakage of medium within the system lines.
In order to achieve the above object, the present invention provides a water-filled exhaust system of a differential pressure transmitter, comprising:
a system pipeline, wherein a load cell is arranged in the system pipeline; and
the differential pressure transmitter is provided with a positive pressure side and a negative pressure side, the front end of the load cell is connected to the positive pressure side of the differential pressure transmitter through an instrument pipeline and a positive pressure side primary isolation valve and a positive pressure side secondary isolation valve which are arranged on the instrument pipeline in sequence, the rear end of the load cell is connected to the negative pressure side of the differential pressure transmitter through an instrument pipeline, a negative pressure side primary isolation valve and a negative pressure side secondary isolation valve which are arranged on the instrument pipeline in sequence, and a balance valve is connected between the instrument pipeline of the positive pressure side secondary isolation valve, which is close to one side of the differential pressure transmitter, and the instrument pipeline of the negative pressure side secondary isolation valve, which is close to one side of the differential pressure transmitter;
the differential pressure transmitter is positioned below the positive pressure measurement secondary isolation valve and the negative pressure side secondary isolation valve;
the pressure measuring cell can build differential pressure on two sides of the pressure measuring cell when the medium in the system pipeline passes through, the pressure of the front end of the pressure measuring cell is high, and the pressure of the rear end of the pressure measuring cell is low.
As an improvement of the water filling and exhausting system of the differential pressure transmitter, the positive pressure side is directly connected with the positive pressure side secondary isolation valve, and the negative pressure side is directly connected with the negative pressure side secondary isolation valve.
As an improvement of the water filling and exhausting system of the differential pressure transmitter, the distance between the positive pressure side secondary isolation valve and the positive pressure side and the distance between the negative pressure side secondary isolation valve and the negative pressure side are 10-30 cm.
As an improvement of the water filling and exhausting system of the differential pressure transmitter, the balance valve is an electric balance valve.
In order to achieve the above object, the present invention further provides a water filling and exhausting method for a differential pressure transmitter, comprising the steps of:
providing a water filling and exhausting system of the differential pressure transmitter; and
and opening a balance valve in a water filling and exhausting system of the differential pressure transmitter to enable a positive pressure side and a negative pressure side of the differential pressure transmitter to be communicated, enabling a medium in the instrument pipeline to flow into the instrument pipeline from the front end of the load cell under the drive of the differential pressure of the front end and the rear end of the load cell, and enabling the medium to flow into the rear end of the load cell through a primary isolation valve on the positive pressure side, a secondary isolation valve on the positive pressure side, a balance valve, a secondary isolation valve on the negative pressure side and a primary isolation valve on the negative pressure side in sequence.
Compared with the prior art, the water filling and exhausting system and method of the differential pressure transmitter have the following advantages: in the water filling and exhausting process, the medium is not leaked, so that the water filling and exhausting work of the differential pressure transmitter can be finished on line, the water filling and exhausting time and risk are reduced, the medium leakage is avoided, and the maintenance condition is provided for the on-line maintenance of the instrument. In addition, the water filling and air discharging work of the instrument is completed by remotely controlling the electric balance valve, so that the air inlet fluctuation problem of the instrument can be remotely eliminated on line.
Drawings
The water filling and exhausting system and method for the differential pressure transmitter and the technical effects thereof are described in detail below with reference to the accompanying drawings and the detailed description, wherein:
FIG. 1 is a schematic diagram of a water-filled exhaust system for a differential pressure transmitter according to the present invention.
In the figure:
10- -system pipeline; 100- -load cell; 20—differential pressure transmitter; 200—positive pressure side; 202- -negative side; 300—positive pressure side primary isolation valve; 302—positive pressure side secondary isolation valve; 304—a negative pressure side primary isolation valve; 306- -negative pressure side secondary isolation valve; 40- -balance valve.
Detailed Description
In order to make the objects, technical solutions and technical effects of the present invention more clear, the present invention will be further described in detail with reference to the accompanying drawings and detailed description. It should be understood that the detailed description is presented herein for purposes of illustration only and is not intended to limit the invention.
Referring to fig. 1, the present invention provides a water filling and exhausting system of a differential pressure transmitter, which includes:
a system line 10, in which a load cell 100 is provided in the system line 10; and
the pressure difference transmitter 20 is provided with a positive pressure side 200 and a negative pressure side 202, the front end of the load cell 100 is connected to the positive pressure side 200 of the pressure difference transmitter 20 sequentially through an instrument pipeline and a positive pressure side primary isolation valve 300 and a positive pressure side secondary isolation valve 302 which are arranged on the instrument pipeline, the rear end of the load cell 100 is connected to the negative pressure side 202 of the pressure difference transmitter 20 sequentially through an instrument pipeline and a negative pressure side primary isolation valve 304 and a negative pressure side secondary isolation valve 306 which are arranged on the instrument pipeline, and a balance valve 40 is connected between the instrument pipeline of the positive pressure side secondary isolation valve 302, which is close to the pressure difference transmitter 20, and the instrument pipeline of the negative pressure side secondary isolation valve 304, which is close to the pressure difference transmitter 20;
wherein differential pressure transmitter 20 is located below positive pressure side secondary isolation valve 302 and negative pressure side secondary isolation valve 306.
According to one embodiment of the present invention, the distances between the positive pressure side secondary isolation valve, the negative pressure side secondary isolation valves 302,306 and the meter pressure taking port are as short as possible, for example, the positive pressure side 200 and the negative pressure side 202 are directly and correspondingly connected with the positive pressure side secondary isolation valve and the negative pressure side secondary isolation valves 302,306, or the distances between the positive pressure side secondary isolation valve 302 and the positive pressure side 200 and between the negative pressure side secondary isolation valve 306 and the negative pressure side 202 are 10-30 cm.
It is emphasized that in the embodiment shown in fig. 1, the balancing valve 40 is an electrodynamic balancing valve, unlike the prior art. The primary function of the electrodynamic balance valve is not just to balance pressure, but also to fill water and vent functions (as described below).
Referring to fig. 1, the working flow of the water filling and exhausting method of the differential pressure transmitter is as follows: according to the water filling and exhausting system of the differential pressure transmitter provided by the invention as shown in fig. 1, for bubbles existing at the upstream of the secondary isolation valves 302 and 306 (the instrument pipeline between the positive and negative pressure side secondary isolation valves 302 and 306 and the system pipeline 10), after the system operates, system fluid passes through the load cell 100, differential pressure is established at two sides of the load cell 100, the pressure at the front end of the load cell 100 is high, the pressure at the rear end is low, at the moment, the electric balance valve 40 is opened, so that the positive pressure side and the negative pressure side of the differential pressure transmitter are communicated, medium in the instrument pipeline flows into the instrument pipeline from the front end of the load cell under the driving of the differential pressure at the two ends of the load cell 10, and sequentially passes through the positive pressure side primary isolation valve 300, the positive pressure side secondary isolation valve 302, the electric balance valve 40, the negative pressure side secondary isolation valve 306 and the negative pressure side primary isolation valve 304 and flows into the rear end of the load cell 10, and thus air bubbles in the instrument pipeline are taken away and flow into the system under the flow of the medium, and water filling and exhausting work of the instrument is completed.
For the bubbles existing in the downstream of the secondary isolation valves 302,306 (the instrument pipeline between the positive and negative pressures 302,306 and the differential pressure transmitter 20), on one hand, the distance between the secondary isolation valves 302,306 and the positive pressure side and the negative pressure side 200,202 is designed to be as short as possible (for example, the distance between the positive pressure side secondary isolation valve 302 and the positive pressure side 200 and the distance between the negative pressure side secondary isolation valve 306 and the negative pressure side 202 are all 10-30 cm), even if the secondary isolation valves 302,306 are directly connected with the instrument pressure taking ports of the positive pressure side and the negative pressure side 200,202 respectively, so that the space for the bubbles existing in the downstream is reduced. On the other hand, the pressure taking port of the differential pressure transmitter and the space thereof are positioned right below the positive pressure side secondary isolation valve 302 and the negative pressure side secondary isolation valve 304, even if air exists in a downstream pipeline, the air automatically floats upwards due to the buoyancy effect of bubbles, enters the upstream of the secondary isolation valves 302 and 306, and then the balance valve 40 is opened, so that the bubbles can be continuously taken away under the condition that the medium in the instrument pipeline flows, and the water filling and the air exhausting work of the instrument is completed.
As can be seen from the above detailed description of the specific embodiments of the present invention, the water-filled exhaust system and method of the differential pressure transmitter of the present invention has the following advantages over the prior art: in the water filling and exhausting process, the medium is not leaked, so that the water filling and exhausting work of the differential pressure transmitter can be finished on line, the water filling and exhausting time and risk are reduced, the medium leakage is avoided, and the maintenance condition is provided for the on-line maintenance of the instrument. In addition, the meter water filling and air discharging work is completed by remotely controlling the electric balance valve 40, so that the problem of meter air inlet fluctuation can be remotely eliminated on line.
The present invention is also capable of suitable alterations and modifications in the above-described embodiments, in light of the above principles. Therefore, the invention is not limited to the specific embodiments disclosed and described above, but some modifications and changes of the invention should be also included in the scope of the claims of the invention. In addition, although specific terms are used in the present specification, these terms are for convenience of description only and do not limit the present invention in any way.
Claims (5)
1. A water-filled exhaust system for a differential pressure transmitter, comprising:
a system pipeline, wherein a load cell is arranged in the system pipeline; and
the differential pressure transmitter is provided with a positive pressure side and a negative pressure side, the front end of the load cell is connected to the positive pressure side of the differential pressure transmitter through an instrument pipeline and a positive pressure side primary isolation valve and a positive pressure side secondary isolation valve which are arranged on the instrument pipeline in sequence, the rear end of the load cell is connected to the negative pressure side of the differential pressure transmitter through an instrument pipeline, a negative pressure side primary isolation valve and a negative pressure side secondary isolation valve which are arranged on the instrument pipeline in sequence, and a balance valve is connected between the instrument pipeline of the positive pressure side secondary isolation valve, which is close to one side of the differential pressure transmitter, and the instrument pipeline of the negative pressure side secondary isolation valve, which is close to one side of the differential pressure transmitter;
the differential pressure transmitter is positioned below the positive pressure measurement secondary isolation valve and the negative pressure side secondary isolation valve;
the pressure measuring cell can build differential pressure on two sides of the pressure measuring cell when the medium in the system pipeline passes through, the pressure of the front end of the pressure measuring cell is high, and the pressure of the rear end of the pressure measuring cell is low.
2. The differential pressure transmitter water-filled bleed system of claim 1, wherein the positive pressure side is directly connected to a positive pressure side secondary isolation valve and the negative pressure side is directly connected to a negative pressure side secondary isolation valve.
3. The differential pressure transmitter water-filled exhaust system of claim 1, wherein the spacing between the positive pressure side secondary isolation valve and the positive pressure side and the negative pressure side secondary isolation valve and the negative pressure side are each 10-30 cm.
4. A differential pressure transmitter water-filled exhaust system as defined in any one of claims 1 to 3, wherein the balancing valve is an electrodynamic balancing valve.
5. A method for water filling and air exhausting of a differential pressure transmitter, comprising the steps of:
providing a differential pressure transmitter water-filled exhaust system of any one of claims 1 to 4; and
and opening a balance valve in a water filling and exhausting system of the differential pressure transmitter to enable a positive pressure side and a negative pressure side of the differential pressure transmitter to be communicated, enabling a medium in the instrument pipeline to flow into the instrument pipeline from the front end of the load cell under the drive of the differential pressure of the front end and the rear end of the load cell, and enabling the medium to flow into the rear end of the load cell through a primary isolation valve on the positive pressure side, a secondary isolation valve on the positive pressure side, a balance valve, a secondary isolation valve on the negative pressure side and a primary isolation valve on the negative pressure side in sequence.
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| CN202110608048.0A CN113483946B (en) | 2021-06-01 | 2021-06-01 | Water filling and exhausting system and method for differential pressure transmitter |
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| CN202110608048.0A CN113483946B (en) | 2021-06-01 | 2021-06-01 | Water filling and exhausting system and method for differential pressure transmitter |
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| CN113483946B true CN113483946B (en) | 2023-04-28 |
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