LINEBREAK DETECTION SYSTEM

摘要

A pipeline break detection system wherein a rate timer valve is opened in response to a predetermined pressure drop to direct pressure fluid to activate the time cycle of an on delay valve and, itself commence a time delay closing cycle. If its closing countdown continues to completion, it depressurizes the on-delay output valve and cancels its countdown. However, if the pipeline experiences a further like pressure drop, before the rate timer valve closes, it will be recharged and held open to keep the output valve timer actuated. If the pipeline pressure fails to level off to allow the rate timer valve to close, and the output relay is thus enabled to complete its timed cycle, the output relay opens to deliver a fluid signal.