WO2020227797A1

WO2020227797A1 - Device for monitoring and positioning valves

Info

Publication number: WO2020227797A1
Application number: PCT/BR2020/050166
Authority: WO
Inventors: Antônio Celso DA FONSECA SPINIELLA
Original assignee: Sense Eletrônica Ltda.
Priority date: 2019-05-15
Filing date: 2020-05-15
Publication date: 2020-11-19
Also published as: BR102019009861A2

Abstract

The invention relates to a device for monitoring and positioning valves, comprising a device (D) that includes a receptacle, microcontroller, Hall-effect sensor, magnet, valve shaft and coil unit, in which the device (D) can be used in single- and dual-action valves, in which the main advantage thereof is to obviate the need for mechanical pre-adjustment.

Description

“DEVICE FOR MONITORING AND POSITIONING OF

VALVES ”

APPLICATION FIELD

[001] The present invention is contained in the field of application of electronic devices and equipment, more precisely in the field of electronic devices applied in the area of metrology, control and automation.

[002] The said invention consists of a device for control in an industrial process, more specifically a device for monitoring and positioning control valves which allows its calibration in an automatic way, applied in rotary and linear valves, simple and double action, providing precise positioning for actuators and valves.

TECHNICAL STATUS

[003] The automation of an industrial process is basically done by primary elements that are process sensors, control elements that, using the information from the sensors, make decisions to act on the processes through final elements and thus proceed with the control of variables, keeping them within pre-established limits.

[004] The final elements are, therefore, mechanisms that control the amount of fluids, liquids and gases that pass through a pipe, in response to the signal sent by the controller, in order to keep these quantities in a value, or range of values, predetermined. These final control elements can be operated by electrical, pneumatic or mechanical means.

[005] The control valve is the final element most used in industrial control systems. Commonly pneumatically operated, the valve was, in the past, sufficient to have the process controlled and keep the industrial plant producing within optimized parameters.

[006] Subsequently, with the development of new tools for mathematical modeling, industrial processes started to have an availability of finer and more precise controls to improve the performance and reliability of the control valve. With that, the processes started to use the positioners, these being elements that guarantee that the valve stem approaches as close as possible to the ideal opening. Said positioners work in conjunction with the control valve actuator to correctly position the plug in relation to the valve seat.

[007] The positioner also compares the signal emitted by the controller with the position of the valve stem and sends the air pressure to the valve actuator necessary to place the plug in the correct position, therefore, the function of the positioner is to ensure that the opening of the valve control valve is as close as possible to the output signal from the controller. Additionally, the positioners are related to the valve's operating dynamics, that is, its opening or closing time, response speed of the controlled variable, as well as the reduction of undesirable oscillations in the processes.

[008] The positioner, like the controller, has control parameters that need to be configured to avoid undesirable oscillations in the process. With the inclusion of digital technology in the constructive design of the positioners, they are no longer considered as a simple accessory of the valve, such as, for example, pressure gauges and air regulating filters, and have started to have a more relevant position in the control loop, contributing to make information available in real time to process engineers, thus assisting in the mathematical modeling used for control and automation.

[009] Digital positioners can also monitor the intensity and use of the control valves identifying and providing information on the need for preventive maintenance of control valves through diagnostic functions.

[0010] The state of the art reliably reflects the evolution of valve positioners so that some documents indicate the evolution of these elements over time, such as document number PI9507472-4, under the title “VALVE POSITIONER”, deposited in 09/23/1997, whose ownership belongs to ROSEMOUNT INC., Which, according to its summary, features a valve positioner (26) that controls the operation of a valve (32) in a process control system. The valve positioner (26) is coupled to a process control circuit (24a, 24b) over which it receives a signal representative of a desired valve position and operating power to the positioner (26). The valve positioner (26) controls a pneumatic actuator (30) which in turn controls the position of the valve (32). The valve positioner (26) includes a microprocessor (52), digital circuit and associated analog circuit.

[001 1] Another example of valve positioners can be seen in document number BR1 12017019694-8, under the title “PROCESS VALVE ARRANGEMENT, PROCESS VALVE POSITIONER AND USE OF A FLUID VALVE ARRANGEMENT”, under METSO's ownership FLOW CONTROL OY, deposited on 03/15/2016, which, according to its summary, features a fluid valve arrangement (20) for the control of a single-acting or double-acting actuator comprising a valve body ( 201) having a central hole (202) with at least one supply port to receive a fluid supply under pressure, at least one actuator port (C1, C2) to provide a control fluid pressure to an actuator, and at least an exhaust port (EX1, EX2). The fluid valve arrangement comprises at least a pair of counter-action calibrating edges operationally secured by a movable rod (203) within said central hole in an axial direction through the pilot force. Each calibrating edge of each counter-action pair comprises a joint seat surface (PS1, PS2, PS3, PS4) on the valve body or stem, and an axial seat ring (PR1, PR2, PR3, PR4) supported by a flexible element (SD1, SD2, SD3, SD4) on the valve post or on the stem to allow relative axial movement of the ring axial seat and support valve body or stem also in a closed state of the respective calibrating edge. The present invention also relates to a process valve positioner and to a use of the fluid valve arrangement in the control of a process valve.

[0012] Finally, another solution understood in the state of the art refers to the object presented by the document WO2013034179, deposited on 03/14/2014 under the title “VALVE POSITIONER AND VALVE MONITORING SYSTEM”, whose ownership belongs to ABB AS, WEEMES PHILLIP and JELLUM EDGAR, which, according to their summary, comprises a valve positioner (1) composed of a valve information and operation unit adapted to obtain operational information about the valve (14); a wireless transmitter adapted for transmitting a wireless communication signal comprising the communication message to the central valve monitoring unit (6); and an antenna adapted to transmit the wireless communication signal. The invention also deals with a central valve monitoring unit (6), a valve monitoring system (10), as well as a method of using the valve positioner (1) to improve a valve monitoring system (10) .

[0013] However, the aforementioned documents share the same shortage, which refers to the need for manual calibration of the positioners, since to indicate the position regarding the total opening of the valve and its total closing, an operator or The instrumentalist performs an operation called mechanical pre-adjustment, where the position referring to 50% of the valve opening is manually adjusted with the position of 50% of the axis magnet. [0014] In this way, the state of the art would benefit from the introduction of a device for monitoring and positioning of valves, which can be applied both in control valves and in other types of valves, with such a monitoring and positioning device dispensing the mechanical pre-adjustment, performing the calibration of the valve shaft excursion automatically, through the use of magnets fixed on the valve axis itself, which allow an accurate reading of the valve position.

OBJECTIVES OF THE INVENTION

[0015] The present invention aims to present a device for monitoring and positioning of valves, applied in control valves and the like, these being single or double acting, where such a device does not require mechanical pre-adjustment for calibration.

[0016] Another objective of the invention is to present a device for monitoring and positioning of valves that performs a self-calibration of the movement excursion of the control valve, thus reducing the time of assembly of the device and the costs with labor and commissioning in the field.

[0017] It is also an objective of the invention to present a device for monitoring and positioning of valves having a modular construction with encapsulated electronics, providing greater protection to the device against ingress of solid and liquid particles.

[0018] It is still an objective of the present invention to present a device for monitoring and positioning of valves comprising a local interface with the operator, allowing greater interaction between the operator and the device at the site of its application.

[0019] Finally, it is the objective of the present invention to present a device for monitoring the positioning of valves that make it possible to mount it in any position of the valve shaft, resulting in greater flexibility in its application.

BRIEF DESCRIPTION OF THE INVENTION

[0020] In accordance with the proposed objectives, the aforementioned invention features a valve monitoring and positioning device which features a constructivity containing magnets, Hall type sensors and software system responsible for the balance between the input signal and stem position of the actuator.

[0021] The present invention has an electromagnetic coil that provides a variable electric current depending on the input signal, and this current increases as the input signal increases, thus creating a magnetic attraction between the nozzle and the reed, resulting in a restriction between them, in addition to increasing the pressure of said nozzle.

[0022] The valve monitoring and positioning device detects the position of the control valve through the detection system provided by the Hall-type sensor, which is electrically connected to the microcontroller plate so that the valve stem continues to move until the position suitable for the input signal is reached. Once the proper position is reached, the microcontroller plate stabilizes the current in the electromagnetic coil and the spool valve is in its equilibrium position.

[0023] The calibration and configuration of the monitoring and positioning device are carried out by the operator through magnetic buttons so that the approach of a magnetic switch activates the configuration mode.

BRIEF DESCRIPTION OF THE DRAWINGS Figure 1 shows a perspective view of the device for monitoring and positioning valves, indicating two outlets and an air inlet; figure 2 shows a front view of the device for monitoring and positioning valves; figure 3 shows a rear view of the device for monitoring and positioning valves; figure 4 shows a left side view of the device for monitoring and positioning valves; figure 5 shows a right side view of the device for monitoring and positioning valves; figure 6 shows a top view of the device for monitoring and positioning the valve; figure 7 shows a bottom view of the device for monitoring and positioning the valve; figure 8 shows an exploded perspective view of the device for monitoring and positioning valves; figure 9 shows a perspective view, in longitudinal section, of the device for monitoring and positioning valves, indicating the valve shaft, the valve shaft magnet and the reed spout; figure 10 shows a perspective view in section of the valve monitoring and positioning device, highlighting the display and the magnetic switches indicating their respective positions; figure 11 shows a perspective view of the valve monitoring and positioning device with the lid open, indicating the coil assembly with the reed spout, the return spring and the diaphragm; figure 12 shows a detailed perspective view of the microswitches; figure 13 shows a side view, in cross section, highlighting the Hall type sensor, the valve shaft magnet and the connection plates; and figure 14 shows a perspective view, in longitudinal section, of the monitoring and positioning device indicating the internal position of the spool valve.

DETAILED DESCRIPTION OF THE INVENTION

[0024] In accordance with the objectives listed and with the figures mentioned, the present invention "DEVICE FOR MONITORING AND POSITIONING OF VALVES", presents a device (D) for monitoring and positioning of valves, these being single or double acting, said device (D) consisting of a receptacle (1) comprising a microcontroller (2), a spool valve (3), a Hall type sensor (4) and a magnet (5), located on the upper axis face valve (6).

[0025] The receptacle (1) of the device (D) has a substantially parallelepipedal shape, where its upper portion has a lid (11) connected to the central portion (12) of the receptacle (1) by means of four elements of fixing, these being preferably screws, located at each of the four ends of said cover (11). Said cover (11) has a display on its upper face which allows the visualization of the elements shown by the hexagonal display (130), located on the microcontroller plate (7).

[0026] The central portion (12) of the receptacle (1) has a lateral portion (110) where two pneumatic outlets (121 a and 121 b) and a pneumatic inlet (122) are located, in addition to one or more manometers ( 123). Said central portion (12) has on its lower face a central hole (124) that serves as a passage for the valve shaft (6).

[0027] The device (D) further comprises a microcontroller plate (7), disposed under the cover (11) of the receptacle (1), said microcontroller plate (7) having a hexagonal display (130) , good as magnetic keys (125), preferably three, positioned below said hexagonal display (130), and said magnetic keys (125) are responsible for allowing the user or operator to perform the necessary calibration and adjustments.

[0028] Other advantages consistent with the use of magnetic keys (125) are that they allow the user or operator to carry out the adjustments and calibration of the device (D) without the need to remove the cover (1 1), using, for this purpose , magnetic buttons and consequently contributing to the increase of the useful life of said device (D), as well as increasing the security inherent to its operation, since it inhibits access to magnetic keys (125) by unauthorized people, that is, without access to the magnetic buttons and avoiding undue changes in the magnetic polarization sequences of the drives.

[0029] The bottom face of the microcontroller board (7) of the device (D) has a Hall-type sensor (4), which is directly aligned with the through hole (81) of the connection plate (8), where the function of said Hall-type sensor (4) is to work together with the magnet (5) of the valve shaft (6).

[0030] Below the microcontroller board (7) there is a connection board (8), with at least two microswitch switches (82) and several electrical connections (83), whose function is to allow the setting of limits for generation alarms. The connection plate (8) has, in its central portion, a through hole (81) which allows the passage of the valve shaft (6) and consequently allowing the magnet (5), located on the upper face of the valve shaft ( 6), approach the Hall type sensor (4).

[0031] The device (D), still in its receptacle (1), more precisely below the connection plate (8), accommodates a coil assembly (9) containing an electromagnetic coil, a nozzle and a reed; a diaphragm (20), a return spring (30) and a spool-type valve (3). [0032] The coil assembly (9) works in convergence with the microcontroller (2) so that said microcontroller (2), through an algorithm, compares the collected input signal and the feedback signal from the Hall type sensor (4), determining a current value that is passed on to the electromagnetic coil of the coil assembly (9), creating an electromagnetic attraction between the nozzle and the reed, restricting the action of the nozzle by the reed and increasing the pressure exerted by the nozzle.

[0033] The increase in pressure exerted by the nozzle, in turn, causes a displacement in the diaphragm (20), where this displacement of the diaphragm (20) displaces the return spring (30) and provides the opening of the spool-type valve ( 3), increasing the air pressure at the pneumatic outlet (121 a) and creating a depression at the pneumatic outlet (121 b), so that increasing the air pressure at the pneumatic outlet (121 a) moves the valve shaft (6 ) until the microcontroller (2) identifies that the correct position has been reached. Once the correct position of the valve shaft (6) is reached, the microcontroller (2) stabilizes the electrical current sent to the coil assembly (9) so that the spool-type valve (3) remains in balance.

[0034] The decrease in pressure exerted by the nozzle, in turn, results in a proportional opposite movement in the valve shaft (6).

[0035] The reading of the valve shaft position (6) performed through the Hall sensor (4) is produced without mechanical contact and provides a very precise capture of the valve shaft position (6) and a generation of digital information linearly, which is sent to the microcontroller (2) for proper processing.

[0036] The device (D) uses a 12-bit digital encoder from 0 to 360 ^Q as a Hall type sensor (4), which is a 16-pin chip, model AS5055A, to monitor the position of the axis of the valve (6) being that this model internally has an encapsulated Hall sensor which is positioned axially to the valve axis (6). This chip has an integrated Hall element array, which provides a high resolution of the offset angle reading, without no mechanical coupling to the valve shaft (6), also providing a long service life to the system due to the absence of mechanical wear. The information of the angular position of the valve read by the sensor is transmitted to the microcontroller (2).

[0037] The device (D) is designed following standards that define requirements for suitability for use in areas with a potential risk of explosion, which are very common in industrial environments and which require the certification of the equipment for safe operation. The device (D) uses Exd protection, explosion proof, and Exi, intrinsic safety, these being two design methods accepted worldwide to operate in areas where the presence of the explosive atmosphere is constant.

[0038] Optionally, the device (D) allows the configuration and calibration of its operating parameters by means of a communication protocol of the HART type made available through user interface tools.

[0039] The device (D), optionally to the microcontroller (2), allows the communication of the position of the valve shaft (6) through a 4 to 20 mA loop.

[0040] The device (D) is adaptive equipment, that is, regardless of the position in which it is mounted on the valve shaft (6), said device (D) must ensure that the opening of the control valve is as close as possible. close to the output signal collected by the microcontroller (2) and for that, it uses a system to measure the position of the valve shaft (6), by means of magnets (5), that is, without mechanical contact. Therefore, the great advantage of this product in relation to the conventional positioners included in the state of the art is that to perform the positioning of the control valve they need a mechanical pre-adjustment, where the operator / instrumentalist has to manually adjust the position of 50% opening valve with the position of 50% of the axis magnet, allowing self-calibration in the valve. [0041] Therefore, the device (D) presents an innovative solution in which it is possible to self-calibrate the movement excursion of the control valve without the need for mechanical pre-adjustment during assembly. This unprecedented feature provides savings in assembly time and labor, reflecting lower commissioning costs in the field.

[0042] This self-calibration function is made possible due to a software routine designed to treat the information generated by the position reading system and an internal adjustment made during the production of the equipment, which is the positioning of the magnet (5) on the axis of the valve (6), in order to take advantage of the larger region of stable magnetic field in relation to the Hall-type sensor (4) mounted on the microcontroller board (7).

[0043] Another advantage presented by the device (D) is its modular construction with encapsulated electronics for protection against the ingress of solid and liquid particles, as well as its local interface with the operator through the hexagonal display (130), type valve spool (3), manifolds for pneumatic connection positioned on the pneumatic outlets (121 a and 121 b) and the pneumatic inlet (122); and pressure gauges (123).

[0044] It is also an advantage presented by the device (D) the possibility of configuring the operation of the equipment through magnetic keys (125), thus avoiding any mechanical wear of the adjustment element.

[0045] Finally, one more advantage presented by the device (D) is its construction in a modular and compact way that provide an easy adaptation to the spaces available for installation and consequent cost reduction.

[0046] It should be understood that the present description does not limit the application to the details described herein and that the invention is capable of other modalities and to be practiced or performed in a variety of ways, within the scope of the claims. Although specific terms have been used, these terms should be interpreted in a generic and descriptive sense, and not for the purpose of limitation.

Claims

1. “DEVICE FOR MONITORING AND VALVE POSITIONING”, applicable to single and double action valves, characterized by the fact that the device (D) comprises a receptacle (1) having a cover (11), central portion (12) and lateral portion (110); a microcontroller board (7) containing a microcontroller (2) and a Hall-type sensor (4); a connection plate (7); a spool valve (3); a valve shaft (6); a magnet (5) and a coil assembly (9).

2. "DEVICE", according to claim 1, characterized by the fact that the receptacle (1) of the device (D) has a parallelepipedal shape where the cover (11) connects to the central portion (12) through localized fastening elements at the ends of said cover (11).

3. "DISPOSITVO", according to claims 1 and 2, characterized by the fact that the cover (11) has a display on its upper side.

4. "DEVICE" according to claims 1, characterized in that the central portion (12) of the receptacle (1) has a lateral portion (1 10).

5. "DEVICE" according to claims 1 and 4, characterized in that the side portion (1 10) has two pneumatic outlets (121 a and 121 b), a pneumatic inlet (122) and at least one manometer ( 123).

6. "DEVICE", according to claims 1 and 4, characterized by the fact that the central portion (12) has a central hole (124) in its lower face.

7. “DEVICE”, according to claim 1, characterized by the fact that the microcontroller plate (7) is located under the cover (11) of the receptacle (1).

8. "DEVICE", according to claims 1 and 7, characterized by the fact that the microcontroller board (7) has a hexagonal display (130) and three magnetic keys (125) below said hexagonal display (130).

9. “DEVICE”, according to claims 1 and 7, characterized by the fact that the Hall-type sensor (4) is located on the underside of the microcontroller plate (7), aligned with the through hole (81) of the connection plate (8).

10. "DEVICE", according to claims 1, 7 and 9, characterized by the fact that the device (D) has a connection plate (8) located below the microcontroller plate (7).

11. “DEVICE”, according to claim 1 1, characterized by the fact that the connection plate (8) has two microswitch switches (82) and electrical connections (83).

12. "DEVICE" according to claims 9, 10 and 11, characterized by the fact that the connection plate (8) has a through hole (81) in its central portion.

13. “DEVICE”, according to claim 1, characterized by the fact that the coil assembly (9) is located below the connection plate (8) inside the receptacle (1).

14. "DEVICE" according to claims 1 and 13, characterized in that the coil assembly (9) comprises an electromagnetic coil, a nozzle and a vane, a diaphragm (20), a return spring (30) and a spool-type valve (3).

15. "DEVICE", according to claims 1 and 14, characterized by the fact that the microcontroller (2) controls the coil assembly (9) through an algorithm.

16. “DEVICE”, according to claim 15, characterized by the fact that the microcontroller algorithm (2) compares the signal collected by the microcontroller with the feedback signal from the Hall-type sensor (4) and determining a current value for the electromagnetic coil of the coil assembly (9).

17. “DEVICE”, according to claim 16, characterized by the fact that the current of the electromagnetic coil of the coil assembly (9) results in an electromagnetic attraction between the nozzle and the vane.

18. "DEVICE", according to claims 15 and 16, characterized by the fact that the electromagnetic attraction between the nozzle and reed in the coil assembly (9) displaces the diaphragm (20) which in turn displaces the return spring ( 30), opening the spool-type valve (3).

19. “DEVICE” according to claims 1, 5 and 18, characterized by the fact that the opening of the spool valve (3) increases the air pressure at the pneumatic outlet (121 a) and a depression at the pneumatic outlet (121 b ).

20. "DEVICE" according to claims 1 and 19, characterized in that the air pressure at the pneumatic outlet (121 a) moves the valve shaft (6).

21. “DEVICE”, according to claims 1, 15 and 16, characterized by the fact that the microcontroller (2) through its algorithm identifies the correct position of the valve shaft (6) and stabilizes the current sent to the coil assembly (9).

22. “DEVICE”, according to claims 1, 20 and 21, characterized by the fact that the magnet (5) is located on the upper face of the valve shaft (6).

23. “DEVICE”, according to claims 1, 9 and 16, characterized by the fact that the Hall-type sensor (4) is an encoder from 0 to 360 ^Q , digital 12 bits, with 16 pins.

24. "DEVICE" according to claims 23, characterized by the fact that the Hall-type sensor (4) is positioned axially to the valve shaft (6).

25. "DEVICE" according to claims 1, 21, 22 and 24, characterized in that the valve shaft (6) is positioned through the through hole (81) and the central hole (124).