Interlocking, automatic operation
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In the tank area, why is the isolation valve at the inlet equipped with interlock, while there is none at the outlet? When will its automation be put into operation?
The interlock mechanism designed for the inlet shut-off valve (which should use the output from the tank’s level gauge as the triggering condition) exists to prevent overflow due to excessively high liquid levels, or damage to the tank and piping equipment caused by too high internal pressure. No interlock mechanism has been designed for the outlet shut-off valve, presumably also for safety reasons; after all, the impact of emptying the contents from the tank is less severe than having an excessively high fill level. I’m not sure if this understanding is correct
The interlock mechanism designed for the inlet shut-off valve (which should use the output from the tank’s level gauge as the triggering condition) exists to prevent overflow due to excessively high liquid levels, or damage to the tank and piping equipment caused by too high internal pressure. No interlock mechanism has been designed for the outlet shut-off valve, presumably also for safety reasons; after all, the impact of emptying the contents from the tank is less severe than having an excessively high fill level. I’m not sure if this understanding is correct
The tank area is a zone with a high safety level, and its interlock design should be of the fail-safe type. For tank containers, the primary concern is ensuring their safety in the event of failures; the inlet shut-off valves should be capable of opening electrically or pneumatically. I’m not sure whether you are referring to an emergency shutdown interlock or a control interlock. Given that an automatic mode is mentioned, it should be a control interlock, that is, a two-position control system that uses the liquid level as the control parameter, and which automatically shuts off the inlet flow when the liquid level reaches a high value. Or switch to the inlet of another tank. This is mainly for the safety of the control tank; think about it the other way around – what would happen if there was no interlock at the inlet?