Differential pressure transmitter for chemical pipeline

Abstract

The utility model provides a differential pressure transmitter for a chemical pipeline, which relates to the technical field of pressure measurement and comprises a shell, and a pressure joint is fixedly inserted into one end of the shell; the other end is connected with an aviation plug male head; the pressure connector comprises a connecting section and a sensor section, a differential pressure sensor assembly is arranged in the sensor section, and the connecting section is used for being inserted into a tested chemical pipeline in a sealed mode; the low-pressure flow channel is formed in the connecting section and is communicated with the negative electrode end of the differential pressure sensor assembly; the high-pressure flow channel is obliquely formed in the connecting section and is communicated with the positive electrode end of the differential pressure sensor assembly; the circuit board is fixedly arranged in the shell, electrically connected with the aviation plug male head and the differential pressure sensor assembly and used for collecting differential pressure sensor signals and transmitting the differential pressure sensor signals to an external data processing system. According to the utility model, the low-pressure flow channel and the high-pressure flow channel which are staggered and not communicated are arranged on the pressure joint in the chemical pipeline to be measured, and measurement can be realized only by arranging one measuring hole on the pipeline to be measured, so that the hidden danger of leakage of the pipeline to be measured is reduced.

Description

Technical Field

[0001] The utility model relates to the technical field of pressure measurement, in particular to a differential pressure transmitter used for chemical pipelines. Background Art

[0002] The differential pressure transmitter is a typical self-balancing detection instrument. It uses the working principle of negative feedback to overcome the influence of adverse factors such as component materials and processing technology. The differential pressure transmitter is used to prevent the medium in the pipeline from directly entering the transmitter. The pressure-sensitive diaphragm and the transmitter are connected by a capillary filled with fluid. It is used to measure the liquid level, flow rate and pressure of liquid, gas or steam, and then convert it into an electrical signal output. The measurement principle of the differential pressure transmitter is: the high-pressure and low-pressure media measured in the pipeline pass through the pressure-leading pipeline to transfer the media to the isolation diaphragms at both ends of the differential pressure sensor, and then the differential pressure sensor converts the pressure signal into an electrical signal, and the electrical signal of the sensor is amplified and processed by the transmitter circuit and transmitted to the back-end acquisition circuit.

[0003] The traditional differential pressure transmitter connects the symmetrical pressure interfaces at both ends of the differential pressure sensor to the joints on the measured pipeline to achieve the transmission measurement of high and low pressure media, and then the processing circuit transmits the signal processing to the back end. This structure requires opening two measurement holes on the measured pipeline and leading out two joints, which is not convenient for installation and is prone to pressure leakage at the pipeline connection point. Utility Model Content

[0004] The purpose of the utility model is to provide a differential pressure transmitter for chemical pipelines to solve the problems existing in the above-mentioned prior art. Staggered and unconnected low-pressure flow channels and high-pressure flow channels are opened on the pressure joint located in the chemical pipeline to be measured. Only one measuring hole needs to be opened on the measured pipeline to achieve measurement, thereby reducing the hidden danger of leakage in the measured pipeline.

[0005] To achieve the above purpose, the utility model provides the following solutions:

[0006] The utility model provides a differential pressure transmitter for a chemical pipeline, comprising: a housing; an aviation plug male head, which is fixedly arranged at one end of the housing and can be externally connected to an aviation plug female head; a pressure joint, the pressure joint comprising a connecting section and a sensor section, a differential pressure sensor assembly is arranged in the sensor section, and the sensor section is fixedly and sealedly inserted at one end of the housing away from the aviation plug male head, and the connecting section is used for being sealed and inserted in the chemical pipeline to be measured; a low-pressure flow channel, which is opened in the connecting section and arranged along the axial direction of the connecting section, and can convey the low-pressure medium in the chemical pipeline to the negative end of the differential pressure sensor assembly through a low-pressure port opened on the side wall of the connecting section; a high-pressure flow channel, which is obliquely opened in the connecting section, and its axial direction is arranged at an angle with the axial direction of the connecting section, and the high-pressure flow channel can convey the high-pressure side medium in the chemical pipeline to the positive end of the differential pressure sensor assembly through a high-pressure port opened at one end of the connecting section away from the housing; a circuit board, which is fixedly arranged in the housing and electrically connected to the aviation plug male head and the differential pressure sensor assembly respectively.

[0007] Optionally, the connecting section and the sensor section are integrally formed, and a plug-in groove is provided on the side wall between the connecting section and the sensor section, and a sealing member is fixedly provided on the side wall of the plug-in groove close to one end of the sensor section; the connecting section is inserted into the detection hole of the chemical pipeline, and the sealing member at the plug-in groove is fixedly and sealedly connected to the detection hole.

[0008] Optionally, a first O-ring is provided on the fixing ring on the side wall of the connecting section. After the connecting section is inserted into the chemical pipeline, the first O-ring can prevent the high-pressure port and the low-pressure port from being connected.

[0009] Optionally, a step groove is provided at one end of the sensor section located in the shell, the sensor assembly is fixedly disposed in the step groove, and one end of the low-pressure flow channel passes through the bottom of the step groove and is connected to the low-pressure side of the sensor assembly, a side channel is provided in the connecting section, one end of the side channel is connected to the high-pressure flow channel, and the other end passes through the step of the step groove and is connected to the high-pressure side of the sensor assembly, and the high-pressure side and the low-pressure side of the sensor assembly are not connected.

[0010] Optionally, the sensor assembly includes a differential pressure base, on which a differential pressure sensor is provided, and a differential pressure welding seat is fixedly welded to one end of the differential pressure base close to the connecting section, the differential pressure welding seat abuts against the bottom of the step groove, and the differential pressure welding seat is provided with a connecting channel for connecting the negative terminal on the low-pressure side of the differential pressure sensor with the low-pressure flow channel; a welding ring is fixedly welded to the other end of the differential pressure base, and a side wall of one end of the differential pressure base close to the welding ring is provided with a medium passage connecting the positive terminal on the high-pressure side of the differential pressure sensor and the side channel.

[0011] Optionally, a second O-ring is fixedly provided between the outer side wall of the differential pressure welding seat and the inner side wall of the stepped groove, and the second O-ring can isolate the connecting channel from the medium passage.

[0012] Optionally, a third O-ring is fixedly provided between the outer wall of the welding ring and the inner wall of the stepped groove.

[0013] Optionally, it also includes a locking ring, which is fixedly inserted in the stepped groove near the opening position, and the welding ring is fixedly abutted against the locking ring at one end away from the differential pressure base; the circuit board is located between the locking ring and the aviation plug male head.

[0014] Optionally, a heat shrink tube is provided on the circuit board.

[0015] Optionally, one end of the male aviation plug is fixedly inserted in a connector fixing seat, and epoxy resin potting glue is provided at the connection position between the male aviation plug and the connector fixing seat; the connector fixing seat is fixedly inserted at one end of the shell away from the sensor assembly; the female aviation plug is provided with five aviation plug pins, and the aviation plug pins are used for connecting with the male aviation plug; the female aviation plug is connected to a cable.

[0016] Compared with the prior art, the utility model has achieved the following technical effects:

[0017] The utility model discloses a low-pressure flow channel which is opened along the axis direction of the connecting section of the pressure joint, one end of which is connected to the low-pressure port opened on the side wall of the connecting section, and the other end of which can penetrate the stepped groove of the pressure joint and be connected to the negative terminal of the differential pressure sensor; the high-pressure flow channel is arranged obliquely on the connecting section of the pressure joint, one end of which is connected to the high-pressure port at the bottom of the connecting section, and the other end of which is connected to the high-pressure side of the sensor assembly through the side channel, and the high-pressure flow channel and the low-pressure flow channel are arranged at an angle so that there is no interference between the two, and the high-pressure port and the low-pressure port are separated by a sealing ring, and the medium on the high-pressure side and the medium on the low-pressure side are not connected between the high-pressure port and the low-pressure port, so that the differential pressure measurement of the medium in the pipeline can be realized by only opening one measuring hole in the chemical pipeline, thus avoiding the traditional differential pressure change.

[0018] The transmitter needs to be installed with two pressure interfaces, which may cause unreliability or pressure leakage. BRIEF DESCRIPTION OF THE DRAWINGS

[0019] In order to more clearly illustrate the embodiments of the utility model or the technical solutions in the prior art, the drawings required for use in the embodiments will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the utility model. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying creative work.

[0020] Figure 1 This is a schematic diagram of the structure of the differential pressure transmitter used in chemical pipelines of the utility model;

[0021] Figure 2 It is a partial cross-sectional schematic diagram of the differential pressure transmitter used for chemical pipelines of the utility model;

[0022] Figure 3 This is a schematic diagram of the pins of the aviation plug of the differential pressure transmitter used in chemical pipelines of the utility model;

[0023] In the figure: 1-first O-type sealing ring, 2-pressure joint, 3-differential pressure welding seat, 4-second O-type sealing ring, 5-PTFE retaining ring, 6-seal, 7-differential pressure base, 8-welding ring, 9-third O-type sealing ring, 10-locking ring, 11-circuit board, 12-heat shrink tube, 13-housing, 14-epoxy resin potting glue, 15-connector fixing seat, 16-aviation plug male head, 17-aviation plug female head, 18-aviation plug pin. DETAILED DESCRIPTION

[0024] The following will be combined with the drawings in the embodiments of the utility model to clearly and completely describe the technical solutions in the embodiments of the utility model. Obviously, the described embodiments are only part of the embodiments of the utility model, not all of the embodiments. Based on the embodiments in the utility model, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the utility model.

[0025] The purpose of the utility model is to provide a differential pressure transmitter for chemical pipelines to solve the problems existing in the above-mentioned prior art. Staggered and unconnected low-pressure flow channels and high-pressure flow channels are opened on the pressure joint located in the chemical pipeline to be measured. Only one measuring hole needs to be opened on the measured pipeline to achieve measurement, thereby reducing the hidden danger of leakage in the measured pipeline.

[0026] In order to make the above-mentioned purposes, features and advantages of the present invention more obvious and easy to understand, the present invention is further described in detail below in conjunction with the accompanying drawings and specific implementation methods.

[0027] like Figure 1 , Figure 2 and Figure 3As shown, the utility model provides a differential pressure transmitter for chemical pipelines, including a shell 13 for protecting internal components, one end of the shell 13 is fixedly inserted with a pressure joint 2; one end of an aviation plug male head 16 is fixedly inserted in a connector fixing seat 15, and an epoxy resin potting glue 14 is provided at the connection position between the aviation plug male head 16 and the connector fixing seat 15; the connector fixing seat 15 is fixedly inserted at one end of the shell 13 away from the sensor assembly; five aviation plug pins 18 are provided on the aviation plug female head 17, and the aviation plug pins 18 are used to plug with the aviation plug male head 16; the aviation plug female head 17 is connected to a cable; the pressure joint 2 includes a connecting section and a sensor section, a differential pressure sensor assembly is provided in the sensor section, and the connecting section is used to be sealed and inserted in the chemical pipeline to be measured; a low-pressure flow channel is opened in the connecting section It is arranged along the axial direction of the connecting section, and it can transport the low-pressure medium in the chemical pipeline to the negative end of the differential pressure sensor assembly through the low-pressure port opened on the side wall of the connecting section; the high-pressure flow channel is obliquely opened in the connecting section, and its axial direction is set at an angle to the axial direction of the connecting section. The high-pressure flow channel can transport the high-pressure side medium in the chemical pipeline to the positive end of the differential pressure sensor assembly through the high-pressure port opened at the end of the connecting section away from the shell 13. The differential pressure range of the differential pressure sensor assembly is 0-5bar; the circuit board 11 is fixedly arranged in the shell 13, and is electrically connected to the aviation plug male head 16 and the differential pressure sensor assembly respectively, for collecting the differential pressure sensor signal and transmitting it to the external data processing system. A heat shrink tube 12 can be set at the circuit board 11 as needed.

[0028] In order to simplify the structure and the number of parts, the utility model forms the connection section and the sensor section in one piece, and a plug-in groove is provided on the side wall between the connection section and the sensor section. A seal 6 is fixedly provided on the side wall of the plug-in groove near one end of the sensor section. The seal 6 of the utility model adopts an ED ring, which is an industrial seal 6. As a special seal 6 for pneumatic and hydraulic joints such as pipe joints, hydraulic plugs, and transition joints, it has a better sealing effect than the traditional O-ring and can isolate the external environment from the low-pressure port. The connection section is inserted into the detection hole of the chemical pipeline, and the seal 6 at the plug-in groove is fixedly sealed and connected to the detection hole. In order to prevent the medium between the high-pressure port and the low-pressure port from being connected, thereby increasing the measurement accuracy, the utility model is fixedly provided with a first O-ring 1 on the side wall of the connection section. After the connection section is inserted into the chemical pipeline, the first O-ring 1 can prevent the high-pressure port and the low-pressure port from being connected.

[0029] In order to install and position the sensor assembly, a stepped groove is provided at one end of the sensor section of the utility model located in the shell 13, and the sensor assembly is fixedly arranged in the stepped groove. The sensor assembly includes a differential pressure base 7, on which a differential pressure sensor is arranged. A differential pressure welding seat 3 is fixedly welded to one end of the differential pressure base 7 close to the connecting section, and the differential pressure welding seat 3 abuts against the bottom of the stepped groove, and a connecting channel is provided to the differential pressure welding seat 3 for connecting the low-pressure side of the differential pressure sensor with the low-pressure flow channel. One end of the low-pressure flow channel passes through the bottom of the stepped groove and is connected to the low-pressure side of the sensor assembly through the connecting channel; a welding ring 8 is fixedly welded to the other end of the differential pressure base 7, and a side wall of one end of the differential pressure base 7 close to the welding ring 8 is provided with a medium passage connecting the high-pressure side of the differential pressure sensor and the side channel. The side channel is arranged in the connecting section and is arranged parallel to the axis of the stepped groove. One end of the side channel is connected to the high-pressure flow channel, and the other end passes through the step of the stepped groove and is connected to the high-pressure side of the sensor assembly. A second O-ring 4 and a PTFE retaining ring 5 are fixedly arranged between the outer wall of the differential pressure welding seat 3 and the inner wall of the stepped groove. The second O-ring 4 can isolate the connecting channel from the medium passage, thereby preventing the high-pressure side and the low-pressure side of the sensor assembly from being connected. A third O-ring 9 is fixedly arranged between the outer wall of the welding ring 8 and the inner wall of the stepped groove to isolate the medium from the housing 13.

[0030] In order to make the sensor assembly more firmly fixed in the stepped groove, the utility model provides a locking ring 10 on the top of the sensor assembly. The locking ring 10 is fixedly inserted in the stepped groove near the opening position, and the welding ring 8 is fixedly abutted against the locking ring 10 at one end away from the differential pressure base 7. The welding ring 8 and the locking ring 10 are both provided with wire holes for connecting the wires of the circuit board 11, so that the circuit board 11 can be connected to the differential pressure sensor through the wires.

[0031] During operation, the high-pressure medium of the chemical pipeline under test flows in from the high-pressure flow channel at the bottom and is isolated and sealed from the outside world through the first sealing ring. The low-pressure medium of the chemical pipeline under test flows in through the low-pressure flow channel on the side of the connecting section, and the pressures at both ends are isolated and sealed from the outside world by the action of the first sealing ring and the second sealing ring. The two media flow into the isolation diaphragms at both ends of the differential pressure sensor, and the differential pressure signal of the differential pressure sensor is converted into an electrical signal, and then amplified and processed by the back-end circuit and transmitted to the acquisition system to realize differential pressure measurement.

[0032] When media of different pressures flow into the connecting section of the pressure joint 2, the low-pressure medium enters the low-pressure flow channel from the low-pressure port opened on the side wall of the connecting section, flows in through the low-pressure flow channel, and is isolated from the high-pressure flow channel under the action of the first sealing ring, and then the low-pressure medium flows into the negative end diaphragm of the differential pressure sensor through the bottom opening of the step groove and the channel of the differential pressure welding seat 3; the high-pressure medium enters the high-pressure flow channel from the high-pressure port opened at the bottom of the connecting section, flows into the side channel through the high-pressure flow channel, enters the space between the side wall of the differential pressure base 7 and the inner wall of the step groove through the side channel, and then enters the positive end diaphragm of the differential pressure sensor through the medium passage of the differential pressure base 7. The second sealing ring is used to seal and separate the internal space of the step groove, so that the low-pressure medium and the high-pressure medium in the step groove are not connected, and the third sealing ring is used to close the step groove so that the medium therein does not flow into the shell 13. The differential pressure sensor converts the pressure signals of high-pressure and low-pressure media into electrical signals. After the sensor signals are amplified and processed by the circuit board 11, they are transmitted to the acquisition system through the transmission line to realize differential pressure measurement. The housing 13 provides protection for the entire differential pressure transmitter. The utility model realizes the transmission of two differential pressure media in the differential pressure transmitter, avoiding the unreliability or pressure leakage caused by the need to install two pressure interfaces in the traditional differential pressure transmitter.

[0033] The present invention uses specific examples to illustrate the principle and implementation of the present invention. The above examples are only used to help understand the method and core idea of ​​the present invention. At the same time, for those skilled in the art, according to the idea of ​​the present invention, there will be changes in the specific implementation and application scope. In summary, the content of this specification should not be understood as limiting the present invention.

Claims

1. A differential pressure transmitter for chemical pipelines, characterized in that: include: case; An aviation plug male head, which is fixedly arranged at one end of the housing and can be externally connected to an aviation plug female head; A pressure joint, the pressure joint comprises a connecting section and a sensor section, the sensor section is provided with a differential pressure sensor assembly, and the sensor section is fixedly and sealedly inserted at one end of the housing away from the aviation plug male head, and the connecting section is used for sealing and inserting in the chemical pipeline to be tested; A low-pressure flow channel is provided in the connecting section and arranged along the axial direction of the connecting section, and can transport the low-pressure medium in the chemical pipeline to the negative terminal of the differential pressure sensor assembly through a low-pressure port provided on the side wall of the connecting section; A high-pressure flow channel is obliquely opened in the connecting section, and its axial direction is set at an angle with the axial direction of the connecting section. The high-pressure flow channel can transport the high-pressure side medium in the chemical pipeline to the positive end of the differential pressure sensor assembly through a high-pressure port opened at one end of the connecting section away from the shell; The circuit board is fixedly arranged in the shell and is electrically connected to the aviation plug male head and the differential pressure sensor assembly respectively.

2. The differential pressure transmitter for chemical pipeline according to claim 1, characterized in that: The connecting section and the sensor section are integrally formed, and a plug-in groove is provided on the side wall between the connecting section and the sensor section, and a sealing member is fixedly provided on the side wall of the plug-in groove close to one end of the sensor section; the connecting section is inserted into the detection hole of the chemical pipeline, and the sealing member at the plug-in groove is fixedly and sealedly connected to the detection hole.

3. The differential pressure transmitter for chemical pipeline according to claim 1, characterized in that: A first O-ring is provided on the fixing ring on the side wall of the connecting section. After the connecting section is inserted into the chemical pipeline, the first O-ring can prevent the high-pressure port from being connected to the low-pressure port.

4. The differential pressure transmitter for chemical pipeline according to claim 1, characterized in that: A stepped groove is provided at one end of the sensor section located in the shell, the sensor assembly is fixedly arranged in the stepped groove, and one end of the low-pressure flow channel passes through the bottom of the stepped groove and is connected to the low-pressure side of the sensor assembly. A side channel is provided in the connecting section, one end of the side channel is connected to the high-pressure flow channel, and the other end passes through the step of the stepped groove and is connected to the high-pressure side of the sensor assembly, and the high-pressure side and the low-pressure side of the sensor assembly are not connected.

5. The differential pressure transmitter for chemical pipeline according to claim 4, characterized in that: The sensor assembly includes a differential pressure base, on which a differential pressure sensor is provided, and a differential pressure welding seat is fixedly welded at one end of the differential pressure base close to the connecting section, the differential pressure welding seat abuts against the bottom of the stepped groove, and the differential pressure welding seat is provided with a connecting channel for connecting the negative terminal on the low-pressure side of the differential pressure sensor with the low-pressure flow channel; a welding ring is fixedly welded at the other end of the differential pressure base, and a side wall of one end of the differential pressure base close to the welding ring is provided with a medium passage connecting the positive terminal on the high-pressure side of the differential pressure sensor and the side channel.

6. The differential pressure transmitter for chemical pipeline according to claim 5, characterized in that: A second O-type sealing ring is fixedly provided between the outer side wall of the differential pressure type welding seat and the inner side wall of the stepped groove, and the second O-type sealing ring can isolate the connecting channel from the medium passage.

7. The differential pressure transmitter for chemical pipeline according to claim 5, characterized in that: A third O-type sealing ring is fixedly provided between the outer side wall of the welding ring and the inner side wall of the stepped groove.

8. The differential pressure transmitter for chemical pipeline according to claim 5, characterized in that: It also includes a locking ring, which is fixedly inserted in the stepped groove near the opening position, and the welding ring is fixedly abutted against the locking ring at one end away from the differential pressure base; the circuit board is located between the locking ring and the aviation plug male head.

9. The differential pressure transmitter for chemical pipeline according to claim 8, characterized in that: A heat shrink tube is arranged on the circuit board.

10. The differential pressure transmitter for chemical pipeline according to claim 1, characterized in that: One end of the aviation plug male is fixedly inserted in the connector fixing seat, and epoxy resin potting glue is provided at the connection position between the aviation plug male and the connector fixing seat; the connector fixing seat is fixedly inserted at one end of the shell away from the sensor assembly; five aviation plug pins are provided on the aviation plug female, and the aviation plug pins are used to be plugged with the aviation plug male; the aviation plug female is connected to a cable.

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