'Floating' procedure of safety valves during operation of steam boiler - by isolating and pressurising with boiler feed water

摘要

The safety relief valves on the boiler unit ar set to maintain a predetermined steam pressure. One, or a group of valves is first isolated from the boiler and then connected to the feed water supply by actuating a remotely operated valve. After completing the test, the feed water is disconnected and the connection with the boiler restored. The feed water contained in the tested circuit expands back into the boiler. The operation of the valve and other operations required during the testing procedure are remotely controlled from the boiler control room. There may be one or more additional valves between the isolating valve and the feed water pump, partic. a manually operated pressure control valve.