A Quick Acting Device for Arresting Incidental Gross Leakage of Heavy Water during In-Service Inspection of Coolant Channels

Abstract

The paper discusses design of an innovative device that can quickly arrest gross leakage of coolant heavy water in the event of ejection of Special Sealing Plug during in-service inspection(ISI) of coolant channels in Indian PHWRs in shutdown. A Special Sealing Plug forms pressure boundary in the Primary Heat Transport System(coolant heavy water) and permits movement of an Inspection Head inside the coolant channel. The incidental ejection of Special Sealing plug can result in gross leakage of heavy water coolant. A special device has been developed for arresting gross leakage quickly in such an emergency situation.