Redundancy of solenoids in interlocked valves
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This post was last edited by zhoudingshengs on 2023-11-27 at 15:30. The attachment is: Redundancy of solenoids in interlocked valves.
This post was last edited by zhoudingshengs on 2023-11-27 at 14:21, with two example images of control valves attached.
With a redundant solenoid valve configuration, the reliability of the safety interlock control valve is significantly improved. To achieve a redundant configuration for solenoid valves, 2 independent solenoid valves, 2 separately routed signal lines, and 2 control signals that are identical but not on the same DCS card are required. This redundant setup results in a significant increase in project costs; therefore, an ALARP (As Low As Reasonably Practicable) economic analysis is necessary to determine whether the additional investment incurred by introducing redundancy yields a satisfactory return on investment. This aspect must be taken into consideration during the design process. In the critical aspects of control, redundancy is essential.
This post was last edited by zhoudingshengs on 2023-11-27 at 16:28. Images would help make it easier to understand.
Stop misleading people – there are specific conditions under which a redundant configuration of solenoid valves can significantly improve the reliability of safety interlock control valves, and these conditions are not met under normal circumstances.
Take the time to read the content carefully before giving your opinion!
I can see it very clearly. When the failure probability of the valve body itself is much higher than that of the solenoid valve, do you think this conclusion still holds: the reliability of the safety interlock control valve increases significantly with the use of a redundant solenoid valve configuration.
In fact, compared to solenoid valves, components such as actuators and control valve bodies have a higher probability of failure, especially for control valves that require tight shutoff (TSO); the requirement for tight shutoff has a significant impact on the overall failure rate of these valves.