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DE-102024132734-A1 - Method for testing the function of a safety throttle of a valve, computing unit for executing the method, as well as valve and field device with the computing unit

DE102024132734A1DE 102024132734 A1DE102024132734 A1DE 102024132734A1DE-102024132734-A1

Abstract

A method (100) for testing the function of a safety throttle (14a; 14b), in particular a passively designed, valve (10a; 10b) of a process plant is proposed by means of a computing unit (12a; 12b), in particular of the valve (10a; 10b) or of another field device (28a; 28b), wherein in a method step (106) a partial movement of a valve element of the valve (10a; 10b) is triggered, wherein during the partial movement of the valve element at least one detected velocity parameter of the valve element or of a transmission element (22a; 22b) of the valve (10a; 10b) connected to the valve element is made available, wherein in particular a velocity of the valve element can be determined from the velocity parameter, wherein in a further method step (108) the detected velocity parameter and/or a velocity of the valve element determined from the velocity parameter during the Partial movement is compared with a stored limit value of the speed parameter and/or the speed of the valve element, whereby if the limit value is exceeded in a further process step (110) a warning signal is issued to a control system of the process plant, a user and/or an environment of the valve (10a; 10b).

Inventors

  • David Wagner-Stürz
  • Sebastian Herbst

Assignees

  • SAMSON AKTIENGESELLSCHAFT

Dates

Publication Date
20260513
Application Date
20241108

Claims (18)

  1. Method for testing the function of a safety throttle (14a; 14b), in particular a passively designed, of a valve (10a; 10b) of a process plant by means of a computing unit (12a; 12b), in particular of the valve (10a; 10b) or of another field device (28a; 28b), wherein in a method step (106) a partial movement of a valve element of the valve (10a; 10b) is triggered, wherein during the partial movement of the valve element at least one detected velocity parameter of the valve element or of a transmission element (22a; 22b) of the valve (10a; 10b) connected to the valve element is made available, wherein in particular a velocity of the valve element can be determined from the velocity parameter, wherein in a further method step (108) the detected velocity parameter and/or a velocity of the valve element determined from the velocity parameter during the partial movement is compared with a stored limit value of the The speed parameter and/or the speed of the valve element is compared, and if the limit value is exceeded in a further process step (110) a warning signal is issued to a control system of the process plant, a user and/or an environment of the valve (10a; 10b).
  2. Procedure according to Claim 1 , characterized in that the partial movement of the valve element is triggered in such a way that the valve element moves from an open position to a position different from a closed state of the valve (10a; 10b) during the partial movement.
  3. Procedure according to Claim 1 or 2 , characterized in that the partial movement of the valve element is triggered in such a way that the valve element moves out of a substantially fully open position of the valve (10a; 10b) during the partial movement.
  4. Method according to one of the preceding claims, characterized in that in a method step (104) a movement test of the valve (10a; 10b) is triggered before the partial movement is initiated.
  5. Procedure according to Claim 5 , characterized in that during the movement test at least one condition parameter for the partial movement, in particular a starting position of the valve element, an end position of the valve element and/or a distance to be covered, is determined.
  6. Method according to one of the preceding claims, characterized in that the partial movement of the valve element is triggered via a setpoint signal which specifies a setpoint speed of the valve element, wherein the setpoint speed of the setpoint signal is greater than a stored expected speed of the valve element.
  7. Method according to one of the preceding claims, characterized in that in a method step (108) a time for a defined change in position of the valve element is determined as a function of the detected velocity parameter and/or the velocity of the valve element determined from the velocity parameter, wherein the limit value is designed as a time for the defined change in position.
  8. Method according to one of the preceding claims, characterized in that the partial movement of the valve element for testing the function of the safety throttle (14a; 14b) is carried out by controlling a positioner of the valve (10a; 10b) by means of the computing unit (12a; 12b), wherein the positioner is configured to vent and/or aerate a working chamber of a pneumatic actuator (16a; 16b) of the valve (10a; 10b) operatively connected to the valve element.
  9. Procedure according to one of the Claims 1 until 8 , characterized in that the partial movement of the valve element for testing the function of the safety throttle (14a; 14b) is effected by actuating a control valve (18a; 18b) of the valve (10a; 10b) by means of the computing unit (12a; 12b), wherein the control valve (18a; 18b) is designed to vent and/or aerate a working chamber of a pneumatic actuator (16a; 16b) of the valve (10a; 10b) operatively connected to the valve element.
  10. Procedure according to Claim 10 , characterized in that at least one transmission of the at least one detected velocity parameter to the computing unit (12a; 12b) and control of the solenoid valve of the valve (10a; 10b) by means of the computing unit (12a; 12b) to trigger the partial movement takes place via a functionally safe connection.
  11. Computing unit of a valve (10a; 10b) or of another field device of a process plant for carrying out the method (100) according to one of the preceding claims for testing a function of a safety throttle (14a; 14b) of the valve (10a; 10b).
  12. Computing unit according to Claim 12 , characterized by a functionally safe design.
  13. Field device of a process engineering plant with a computing unit (12b) according to Claim 12 and with a communication unit (30b) to a functionally safe communication with the valve (10b).
  14. Valve of a process plant with a safety throttle (14a) and with a computing unit (12a) according to Claim 12 .
  15. valve after Claim 13 , characterized by a pneumatic actuator (16a) and a control valve (18a) for venting and/or de-venting a working chamber of the actuator (16a), wherein the safety throttle (14a) is arranged fluidically, in particular essentially directly, before or after the control valve (18a).
  16. valve after Claim 14 or 15 , characterized by a functionally safe connection between the computing unit (12a) and a sensor (20a) for detecting the speed parameter of the valve element or the transmission element (22a) of the valve (10a) connected to the valve element.
  17. Computer program, comprising instructions which are issued during the execution of the computer program by a computer or a computing unit (12a; 12b), in particular according to Claim 12 , cause this/these to proceed according to one of the procedure (100) Claims 1 until 11 to execute.
  18. Computer-readable storage medium comprising instructions which, when executed by a computer, cause it to perform the method (100) according to one of the Claims 1 until 11 to execute.

Description

State of the art Technical equipment of any kind, including individual machines and entire process plants, poses certain hazards not only directly to operating personnel but also indirectly to the environment and thus to uninvolved persons. The nature and extent of these hazards depend on a multitude of factors, such as the characteristics of the respective technical equipment itself, as well as its operation. Against this background, legislators mandate the preparation of a risk and hazard analysis during the planning phase of such potentially hazardous technical equipment. By designing the technical equipment in accordance with legally established regulations, the identified risks and hazards can be reduced to an acceptable level during the intended operation of the technical equipment. Particularly in the case of complex technical facilities, such as process plants, a process control system is required to establish and maintain an intended operating state. By correcting deviations from the intended operating state that remain within a limited range, a process control system contributes to the safe operation of a process plant. To ensure that even significant deviations from the intended operating state, exceeding the corrective capabilities of the process control system, do not lead to a safety-relevant event, process plants are additionally equipped with a safety system independent of the process control system. While the process control system, in addition to its primary function of process control, also contributes to the safety of the process plant to a certain extent, the sole task of the safety system is to return the process plant to a safe state in the event of safety-critical operating conditions. For this purpose, a safety system comprises at least one so-called safety-instrumented function, which is generally implemented in the form of a sensor, an actuator, and an electronic safety-related controller, also known as a logic module. The safety-related controller determines—independently of the process control system—based on the information supplied by the sensors, whether a safety-critical operating state of the process plant exists and whether intervention by the safety system in the form of the execution of a safety-instrumented function, also known as a safety function, is required. Control valves, especially pneumatically actuated control valves, in process engineering plants are equipped with safety functions designed to move the valve to a safe position in an emergency. Such a safety function typically must meet higher reliability requirements, such as functions for controlling a valve element or similar. In pneumatic actuators, this safety function is usually achieved by a spontaneously triggered rapid venting of the actuator's working chamber, releasing the stored air or other medium via a safety valve. Rapid venting of the working chamber eliminates the force opposing the actuator's return elements, usually springs, thereby moving the valve element to the safe position via these return elements. These return elements are generally quite robust. When the valve element is moved into a position via the return elements, the rapid displacement of the process medium can cause pressure surges within the process plant. These surges can potentially lead to significant damage in other components of the process plant, such as pumps, tanks, and/or other fittings. Such damage can necessitate extensive maintenance and/or repairs, resulting in considerable costs for the process plant. To dampen such movement of the valve element when moving into the safety position, safety throttles are provided, which are positioned upstream or downstream of the safety valve. The safety valve is typically designed as a simple on/off valve. Depending on the plant, process, and/or valve, the safety throttle can then be adjusted to the necessary throttling effect to prevent pressure surges within the process plant when the valve element moves into the safety position. Switching the safety valve can be tested by actuating the safety valve using various methods. However, the safety throttle itself is usually not considered in these tests. This safety throttle can become clogged or otherwise blocked due to prolonged periods of inactivity during valve operation without triggering the safety function, thus preventing rapid venting of the working chamber. Furthermore, it is conceivable that, for example, damage to the safety throttle could cause internal or external blockages. If the safety throttle housing is damaged, the throttling effect of the safety throttle is reduced by unintentional adjustment and/or clogging, and pressure surges can no longer be prevented when the valve's safety function is triggered. In such a case, the entire process plant could be at risk. Advantages of the invention A method is proposed for testing the function of a safety throttle, particularly a passively designed one, of a valve in a process