CN216079859U - Steam soot blower control terminal - Google Patents

Steam soot blower control terminal Download PDF

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Publication number
CN216079859U
CN216079859U CN202122612822.3U CN202122612822U CN216079859U CN 216079859 U CN216079859 U CN 216079859U CN 202122612822 U CN202122612822 U CN 202122612822U CN 216079859 U CN216079859 U CN 216079859U
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China
Prior art keywords
soot blower
circuit board
control terminal
control circuit
steam
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Active
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CN202122612822.3U
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Chinese (zh)
Inventor
周国东
贺延枫
任杰
刘媚存
谢国峰
王吉荣
邵戊辰
孙传军
王淋韵
牛磊
焦玉明
何立荣
郑雪琴
高清超
佟艳亮
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Beijing Bicotest Tech Co ltd
Guodian Inner Mongolia Dongsheng Thermal Power Co Ltd
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Beijing Bicotest Tech Co ltd
Guodian Inner Mongolia Dongsheng Thermal Power Co Ltd
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Priority to CN202122612822.3U priority Critical patent/CN216079859U/en
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Abstract

The utility model relates to a control terminal of a steam soot blower. This steam soot blower control terminal includes: the sensing unit is arranged on the soot blower and is connected with the control circuit board; the control circuit board is also respectively connected with the arrival position limit switch and the retreat position limit switch of the soot blower, and has the characteristic of simple structure. And the control circuit board is used for controlling the on-off of the soot blower according to the data signals collected by the sensor, the signals of the position-entering limit switch and the position-returning switch, so that the problems that the equipment defects are discovered later, the motor failure rate of the soot blower is increased, the service life is shortened and the like in the prior art can be effectively solved.

Description

Steam soot blower control terminal
Technical Field
The utility model relates to the field of boiler soot blowing devices, in particular to a control terminal of a steam soot blower.
Background
The steam soot blower utilizes steam with certain pressure and temperature to spray at high speed through a rotary spray head to clean accumulated dust and coking on the heating surface of the boiler, thereby effectively improving the heat transfer efficiency of the heating surface of the boiler, and achieving the purposes of saving energy and reducing steam consumption.
The prior steam soot blower generally comprises a soot blower valve, an air duct, a spray head, a driving motor, a speed reducer, a shell bracket and the like. All the push soot blowers are provided with an entering position limiting signal and a retreating position limiting signal for judging the position state of the soot blowers, so that the soot blowers are controlled to act, and the soot blowers are prevented from staying in the furnace for a long time under the condition of no steam cold cutting. The outer rotating pipe of the soot blower is sleeved outside the inner fixed pipe, and the motor drives the soot blower sliding seat to move forwards through the speed reducer, the gear and the chain and drives the outer rotating pipe to rotate and push at the same time. The end part of the outer rotating pipe is provided with a spray head, and the spray head is provided with two nozzles in opposite directions, so that the vibration caused by the steam spraying can be reduced. After the soot blower nozzle enters the furnace, a transmission mechanism on the speed reducer body acts, and a spring of the valve is compressed so as to open the steam inlet valve. The soot blower gearbox is provided with a square-mouth screw rod for manually operating the soot blower to advance and retreat, so that a user is allowed to manually operate the soot blower to advance and retreat, and the soot blower is convenient to withdraw from when the equipment is overhauled in a power failure mode and the electric driving device breaks down.
The blowing process of the soot blower is that a motor drives a speed reducer, a toothed rail and a gear chain drive a soot blower sliding seat to move forwards and drive an outer rotating pipe to rotate and push simultaneously. After the soot blower nozzle enters the furnace, a transmission mechanism on the speed reducer body acts, a spring of the valve is compressed, so that the steam inlet valve is opened, and blowing is started. When the outer rotating pipe of the soot blower extends into the furnace for a certain distance, the PLC receives an action signal of the in-position limit switch, controls the motor to rotate reversely, drives the soot blower to move backwards and rotate, when the blowpipe retreats outside the furnace to a proper distance away from the furnace wall, the transmission mechanism on the speed reducer body acts reversely, the valve spring relaxes and closes the steam inlet valve, the soot blower continuously retreats to the in-position limit switch, and the PLC receives the action signal of the in-position limit switch, controls the motor to stop and completes a blowing process.
The traditional soot blower control mode is centralized control, that is, all soot blower signals and power cables adopted by each unit are connected into a common control system, usually controlled by a PLC. Once the public control system has problems, all soot blowers cannot be remotely controlled and can only be manually controlled on site. The position limiting switch that advances and the position limiting switch that withdraws to of traditional soot blower are the physical switch, and under the normal condition of switch, have the advantage that state information is accurate, but in case limit switch breaks down, PLC can not receive the soot blower state, and the soot blower can continue to remove, can only withdraw from the motor until the overcurrent protection action tripping operation of motor or PLC overtime judgement. Under the condition, the equipment defects are discovered later, the motor failure rate of the soot blower is increased, the service life is shortened, and even the boiler pipe blowing leakage accident can be caused by the overlong retention time of the soot blower in the boiler.
SUMMERY OF THE UTILITY MODEL
In order to solve the problems in the prior art, the utility model provides a control terminal of a steam soot blower.
In order to achieve the purpose, the utility model provides the following scheme:
a steam sootblower control terminal comprising: a control circuit board and a sensing unit;
the sensing unit is arranged on the soot blower and is connected with the control circuit board; the control circuit board is also respectively connected with an entering position limit switch and a retreating position limit switch of the soot blower;
the control circuit board is used for controlling the on-off of the soot blower according to the data signals collected by the sensor, the signals of the position-entering limit switch and the position-returning switch.
Preferably, the control circuit board includes: the device comprises a singlechip, a power circuit, a driving circuit and a signal input circuit;
the power circuit, the driving circuit, the signal input circuit and the communication circuit are all connected with the single chip microcomputer; the driving circuit is also connected with the soot blower; the signal input circuit is respectively connected with the sensing unit, the forward position limit switch and the backward position limit switch.
Preferably, the sensing unit includes a temperature sensor, a distance sensor, and a rotation speed sensor;
the temperature sensor, the distance sensor and the rotating speed sensor are all connected with the control circuit board; the temperature sensor is used for collecting the temperature of the outer wall of the soot blower; the distance sensor is used for collecting the distance between a gearbox and a flange in the soot blower; the rotating speed sensor is used for collecting the rotating speed of the motor of the soot blower.
Preferably, the method further comprises the following steps: the device comprises a shell, a key unit and a display screen;
the key unit is connected with the control circuit board; the display screen is connected with the control circuit board; the display screen and the key unit are both arranged on the shell; the control circuit board is arranged inside the shell; the key unit is used for switching a display interface on the display screen and inputting configuration parameters.
Preferably, a human-computer interaction interface is embedded in the display screen.
Preferably, the control circuit board further comprises a communication circuit;
the communication circuit is connected with the singlechip; the communication circuit is used for signal interaction with peripheral equipment.
Preferably, the housing is provided with a mounting hole.
Preferably, the key unit is a film key.
Preferably, the display screen is an LCD liquid crystal display screen.
According to the specific embodiment provided by the utility model, the utility model discloses the following technical effects:
the utility model provides a steam soot blower control terminal, which comprises: the control circuit board and the sensing unit have the characteristic of simple structure, and the control circuit board is used for controlling the on-off of the soot blower according to the data signals collected by the sensor, the signals of the position limiting switch and the position reversing switch, so that the problems that the equipment defect is discovered later, the motor failure rate of the soot blower is increased, the service life is shortened and the like in the prior art can be effectively solved.
Drawings
In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the drawings needed to be used in the embodiments will be briefly described below, and it is obvious that the drawings in the following description are only some embodiments of the present invention, and it is obvious for those skilled in the art to obtain other drawings without inventive exercise.
FIG. 1 is a schematic structural diagram of a steam soot blower control terminal provided by the present invention;
FIG. 2 is a schematic view of a connection structure of a control terminal of a steam soot blower and the steam soot blower provided by an embodiment of the present invention;
FIG. 3 is a schematic structural diagram of a conventional soot blower;
FIG. 4 is an external view of a steam sootblower control terminal provided in an embodiment of the present invention;
fig. 5 is a schematic view of an installation position of a steam sootblower control terminal according to an embodiment of the present invention.
Description of the symbols:
1-1 soot blower valve, 1-2 transmission mechanism, 1-3 junction box, 1-4 toothed rail, 1-5 first flange, 1-6 furnace wall, 1-7 spray nozzle, 1-8 second flange, 1-9 external rotating pipe, 1-10 internal fixed pipe, 1-11 gear chain, 1-12 gear box, 1-13 rear support, 1-14 crossbeam, 1-15 front suspension, 1-16 travel switch, 1-17 traveling box, 1-18 back position limit switch, 1-19 in position limit switch, 1-20 valve opening mechanism, 2-1 sensing unit, 2-2 single chip microcomputer, 2-3 power circuit, 2-4 driving circuit, 2-5 signal input circuit, 2-6 key unit, 2-7 display screens, 2-8 communication circuits, 2-9 boiler DCS systems, 2-10 power supplies, 2-11 rotating speed sensors, 2-12 distance sensors and 2-13 temperature sensors.
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 utility model aims to provide a steam soot blower control terminal to solve the problems that in the prior art, the discovery of equipment defects is late, the failure rate of a motor of a soot blower is increased, the service life is shortened and the like.
In order to make the aforementioned objects, features and advantages of the present invention comprehensible, embodiments accompanied with figures are described in further detail below.
The utility model provides a steam soot blower control terminal, which comprises: a control circuit board and a sensing unit 2-1.
The sensing unit 2-1 is installed on the soot blower, and the sensing unit 2-1 is connected with the control circuit board. The control circuit board is also respectively connected with the inlet limit switches 1-19 and the outlet limit switches 1-18 of the soot blowers.
The control circuit board is used for controlling the on-off of the soot blower according to data signals collected by the sensor, signals of the in-position limit switches 1-19 and signals of the out-position switch.
As shown in fig. 1 and 2, the control circuit board adopted by the present invention includes: 2-2 parts of a singlechip, 2-3 parts of a power circuit, 2-4 parts of a drive circuit and 2-5 parts of a signal input circuit.
The power circuit 2-3, the driving circuit 2-4, the signal input circuit 2-5 and the communication circuit 2-8 are all connected with the singlechip 2-2. The drive circuit 2-4 is also connected to the sootblower. The signal input circuit 2-5 is respectively connected with the sensing unit 2-1, the forward position limit switch 1-19 and the backward position limit switch 1-18.
In order to improve the control precision of the soot blower and avoid the problem that the soot blower has defects and is found later, the sensing unit 2-1 used by the utility model comprises a temperature sensor 2-13, a distance sensor 2-12 and a rotating speed sensor 2-11.
The temperature sensors 2-13, the distance sensors 2-12 and the rotating speed sensors 2-11 are all connected with the control circuit board. The temperature sensors 2-13 are used for collecting the temperature of the outer wall of the soot blower. The distance sensors 2-12 are used for collecting the distance between a gearbox and a flange in the soot blower. And the rotating speed sensors 2-11 are used for acquiring the rotating speed of the motor of the soot blower.
In order to improve the operation performance of the steam soot blower control terminal, a shell, a key unit 2-6 and a display screen 2-7 are further arranged in the steam soot blower control terminal.
The key units 2-6 are connected with the control circuit board. The display screens 2-7 are connected with the control circuit board. The display screen 2-7 and the key unit 2-6 are arranged on the housing. The control circuit board is arranged inside the shell. The key unit 2-6 is used for switching the display interface on the display screen 2-7 and also for inputting configuration parameters. A human-computer interaction interface is embedded in the display screens 2-7, so that a user can control and display various parameters of the steam soot blower control terminal, and the operation convenience of the user is improved. Preferably, the key units 2-6 are membrane keys and the display 2-7 is an LCD screen.
In order to perform data interaction with a peripheral system in real time, the control circuit board adopted by the utility model further comprises a communication circuit.
The communication circuit 2-8 is connected with the singlechip 2-2. The communication circuit 2-8 is used for signal interaction with peripheral devices, such as boiler DCS systems 2-9.
Further, in order to improve the installation convenience of the control terminal of the steam soot blower, the shell is provided with an installation hole, and the specific position of the installation hole is set according to actual needs. Wherein, the installation position of the steam soot blower control terminal is shown in figure 5.
The overall appearance of the steam sootblower control terminal is shown in fig. 4.
The advantages and structure of the steam sootblower control terminal provided above of the present invention will be explained based on a specific embodiment.
As shown in fig. 4 and fig. 1, the front surface of the housing is provided with an LCD display, a membrane key array, and the side surface is provided with four waterproof connectors (fig. 4 only shows a waterproof connector arrangement manner, but not limited thereto, the specific positions of the waterproof connectors may be set according to actual needs). And a power supply 2-10 cable, a driving cable, a communication cable and a signal cable used by the steam soot blower control terminal are led out through a waterproof joint arranged on the side edge of the shell. The rear part of the shell is provided with a thickening design mounting hole which is fixed on the shell of the steam soot blower by using a bolt. The LCD is used for displaying information and performing man-machine interaction, and the displayed information comprises the signal quantity and the signal state acquired by the steam soot blower control terminal and setting parameters required by the soot blower blowing process. The film key array is used for checking and switching a display interface in the LCD and inputting configuration parameters.
As shown in FIG. 2, a control circuit board inside a control terminal of the steam soot blower comprises a singlechip 2-2, a power circuit 2-3, a driving circuit 2-4, a signal input circuit 2-5 and a communication circuit 2-8. The core part of the steam soot blower control terminal adopts a standardized general circuit. The communication circuit 2-8 of the steam soot blower control terminal is connected with the boiler DCS system 2-9 to receive access and control of the DCS, for example, the DCS and the steam soot blower control terminal send and read control commands to the steam soot blower control terminal in a communication mode, and the steam soot blower control terminal returns a controlled result to the DCS. The power supply of the control terminal of the steam soot blower is provided by an external power supply 2-10, and the external power supply 2-10 is converted into electric energy which meets the power supply requirement of a control circuit board through a power circuit 2-3. The steam soot blower control terminal controls the driving circuit 2-4, controls the connection of the external power supply 2-10 and the soot blower motor, and realizes the control of the start and stop and the forward and reverse rotation of the motor.
As shown in FIG. 1, the sensors connected with the signal input circuit 2-5 of the circuit board inside the control terminal of the steam soot blower comprise a temperature sensor 2-13, a distance sensor 2-12 and a rotating speed sensor 2-11. Also connected are a go-to-position limit switch 1-19 and a back-to-position limit switch 1-18. The signals of the in-position limit switches 1 to 19 and the signals of the back-position limit switches 1 to 18 are original switching value signal devices of the soot blowers. The temperature sensor 2-13 is arranged on an inner fixed pipe 1-10 behind the soot blower valve 1-1 and used for measuring the temperature of the outer wall. The distance sensor 2-12 is arranged on the gear box and used for measuring the distance between the gear box and the first flange 1-5 and the second flange 1-8, and the rotating speed sensor 2-11 is arranged on the motor and used for detecting the rotating speed of the motor. Among them, as shown in fig. 3, the conventional steam sootblower includes: 1-1 part of a soot blower valve, 1-2 parts of a transmission mechanism, 1-3 parts of a junction box, 1-4 parts of a toothed track, 1-5 parts of a first flange, 1-6 parts of a furnace wall, 1-7 parts of a spray head, 1-8 parts of a second flange, 1-9 parts of an outer rotating pipe, 1-10 parts of an inner fixing pipe, 1-11 parts of a gear chain, 1-12 parts of a gear box, 1-13 parts of a rear support, 1-14 parts of a girder, 1-15 parts of a front support hanger, 1-16 parts of a travel switch, 1-17 parts of a traveling box, 1-18 parts of a backward position limit switch, 1-19 parts of a forward position limit switch and 1-20 parts of a valve opening mechanism.
As the rotating speed of the motor of the soot blower is collected in the embodiment, the rotating speed of the outer rotating pipe 1-9 of the soot blower, the advancing speed of the spray head 1-7 and the depth of the spray head 1-7 can be calculated by only the sum of the rotating speed ratio of the transmission mechanism 1-2 of the gearbox. When the boiler needs to blow soot during operation, the soot blower is subjected to pushing and withdrawing operations for many times, the steam soot blower control terminal takes data collected by the sensor as a sample for statistical analysis, the action relation between the running time length of the motor, the rotating speed, the 1-7 depth of the spray head and the advancing and withdrawing limit switch is obtained, and the state parameter of the soot blower in place in normal advancing and withdrawing is found, so that the decision of the return flight and the emergency return of the soot blower can be made under the condition of not using advancing and withdrawing limit signal operation.
Since the temperature data of the soot blower valve 1-1 is collected in the embodiment, when the soot blower valve 1-1 is closed and inner leakage exists, the temperature level of the measuring point is different from normal, and the temperature difference is calculated in the steam soot blower control terminal through an operation program embedded into the singlechip 2-2 by utilizing a statistical algorithm such as built-in variance operation and the like (the technology is the prior art, so that detailed description is not given here). When the temperature deviation exceeds the threshold value, the alarm is displayed through the LCD, the alarm result is sent to the DCS, and no matter on-site monitoring personnel or DCS operation monitoring personnel can quickly master the defect condition of the soot blower valve 1-1, so that timely and correct countermeasures can be taken.
As shown in FIG. 5, the present example has the steam sootblower control terminals mounted near the junction boxes 1-3 of the conventional sootblowers for ease of wiring. The thickness of the shell of the steam soot blower is usually not more than 3mm, and the punching installation is very convenient.
The embodiment also has field application: a steam soot blower control terminal and an original centralized control system are respectively installed on a No. 1 boiler soot blower of a certain power plant so as to monitor the working state of the steam soot blower in real time. The monitored working state comprises the advancing and retreating speed and the advancing and retreating depth of the soot blower and the inner leakage condition of the soot blower valve 1-1. The steam soot blower control terminal has the function of remotely and locally controlling automatic switching, when the fault of the advance and retreat limiting stopper occurs, intelligent analysis and judgment can be made in time before the fault is found by the original centralized control system, whether the blowing is continued or the soot blower is emergent to exit is determined, and the effect is good in application.
The utility model grasps the state of the soot blower by monitoring the information of the temperature, the motor rotating speed, the soot blower position and the like behind the steam soot blower valve, thereby logically judging the failure of the soot blower, avoiding the overload damage of the soot blower motor and reducing the boiler pipe blowing damage accident caused by the soot blower valve internal leakage and soot blower failure.
In the specification, the examples are described in a progressive mode, each example focuses on the difference from other examples, and the same and similar parts among the examples are referred to each other.
The principles and embodiments of the present invention have been described herein using specific examples, which are provided only to help understand the method and the core concept of the present invention; meanwhile, for a person skilled in the art, according to the idea of the present invention, the specific embodiments and the application range may be changed. In view of the above, the present disclosure should not be construed as limiting the utility model.

Claims (9)

1. A steam sootblower control terminal, comprising: a control circuit board and a sensing unit;
the sensing unit is arranged on the soot blower and is connected with the control circuit board; the control circuit board is also respectively connected with an entering position limit switch and a retreating position limit switch of the soot blower;
the control circuit board is used for controlling the on-off of the soot blower according to the data signals collected by the sensing unit, the entering position limit switch signals and the returning position switch signals.
2. The steam sootblower control terminal of claim 1, wherein the control circuit board comprises: the device comprises a singlechip, a power circuit, a driving circuit and a signal input circuit;
the power circuit, the driving circuit and the signal input circuit are all connected with the single chip microcomputer; the driving circuit is also connected with the soot blower; the signal input circuit is respectively connected with the sensing unit, the forward position limit switch and the backward position limit switch.
3. The steam sootblower control terminal of claim 1, wherein the sensing unit comprises a temperature sensor, a distance sensor, and a rotational speed sensor;
the temperature sensor, the distance sensor and the rotating speed sensor are all connected with the control circuit board; the temperature sensor is used for collecting the temperature of the outer wall of the soot blower; the distance sensor is used for collecting the distance between a gearbox and a flange in the soot blower; the rotating speed sensor is used for collecting the rotating speed of the motor of the soot blower.
4. The steam sootblower control terminal of claim 2, further comprising: the device comprises a shell, a key unit and a display screen;
the key unit is connected with the control circuit board; the display screen is connected with the control circuit board; the display screen and the key unit are both arranged on the shell; the control circuit board is arranged inside the shell; the key unit is used for switching a display interface on the display screen and inputting configuration parameters.
5. The steam sootblower control terminal of claim 4, wherein a human-computer interface is embedded in the display screen.
6. The steam sootblower control terminal of claim 4, wherein the control circuit board further comprises a communication circuit;
the communication circuit is connected with the singlechip; the communication circuit is used for signal interaction with peripheral equipment.
7. The steam sootblower control terminal of claim 4, wherein the housing is provided with mounting holes.
8. The steam sootblower control terminal of claim 4, wherein the key unit is a membrane key.
9. The steam sootblower control terminal of claim 4, wherein the display screen is an LCD liquid crystal display screen.
CN202122612822.3U 2021-10-28 2021-10-28 Steam soot blower control terminal Active CN216079859U (en)

Priority Applications (1)

Application Number Priority Date Filing Date Title
CN202122612822.3U CN216079859U (en) 2021-10-28 2021-10-28 Steam soot blower control terminal

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
CN202122612822.3U CN216079859U (en) 2021-10-28 2021-10-28 Steam soot blower control terminal

Publications (1)

Publication Number Publication Date
CN216079859U true CN216079859U (en) 2022-03-18

Family

ID=80642377

Family Applications (1)

Application Number Title Priority Date Filing Date
CN202122612822.3U Active CN216079859U (en) 2021-10-28 2021-10-28 Steam soot blower control terminal

Country Status (1)

Country Link
CN (1) CN216079859U (en)

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