Method and apparatus for explosion protection of plants, pipelines and the like by pressure monitoring

A method for automatically controlling a system for automatically initiating protective measures for protecting plant facilities, pipelines and the like from a fire or an explosion wherein a system parameter threshold value is continuously updated to a value which is higher than a prevailing intermediate system parameter value by a safety margin, said method comprising the steps of:

• monitoring successive system parameter values in potentially explosive areas;
• storing one of the successive system parameter values in memory;
• using said stored successive system parameter value an a later successive system parameter value measured subsequently to form an intermediate system parameter value;
• incrementing said intermediate system parameter value by said safety margin to determine said system parameter threshold value;
• continuously repeating the above steps with the stored successive system parameter value being replaced by a more recent system parameter value and continuously updating the intermediate system parameter value and the system parameter threshold value;
• and
• upon said monitored system parameter value exceeding the system parameter threshold value, activating a triggering unit to produce a signal which is conducted to a control means for automatically initiating said protective measures.

An automatic system for automatically coping with an emergency situation in plant facilities, pipelines and the like wherein a system reference variable is continuously updated to a value which is higher than a prevailing means system parameter value by a safety margin, said system comprising:

• sensor means for monitoring successive system parameter values of said system in selected areas, said sensor means being connected to an analog/digital converter arranged to supply signals representing said monitored system parameter values to a control unit and to a comparison means, said control unit supplying at least some of said system parameter values to a memory means for retention in memory and further supplying the monitored system parameter values fed to said memory means to a mean value forming means for calculating a mean value from values fed thereto over a time interval, said means value forming means being connected to a means value incrementing means arranged to increase each said means value supplied to it by said safety margin to create a reference variable, said mean value incrementing means being arranged to supply said reference variable to said comparison means for comparison with said monitored successive system parameter values, said comparison means sending a trigger signal to a triggering means to activate said triggering means upon a monitored system parameter value exceeding said reference variable, and said triggering means automatically producing a signal which is directed to said means for initiating protective provisions for coping with said emergency situation.