AIR-OPERATED VALVE DIAGONOSIS METHOD, AIR-OPERATED VALVE DIAGNOSIS APPARATUS, AND AIR-OPERATED VALVE

摘要

PURPOSE: An air-operated valve diagnosis method, an air-operated valve diagnosis unit, and an air-operated valve are provided to reduce the error of a decision result which maintenance management personals have the difference opinion. CONSTITUTION: An air-operated valve diagnosis method comprises the following steps a preliminary process, a first process, and a validation process. The preliminary process is composed that sound generated while opening/closing is measured and recorded when operating fluid is supplied/discharged to an operating port of an air-operated valve(10) by contacting to an acoustic emission sensor(2) in an initial state of the air-operated valve. The first process is composed that sound generated while opening/closing is measured and recorded when the operating fluid is supplied/discharged to the operating port of the air-operated valve by contacting to the acoustic emission sensor after operating the air-operated valve. The validation process is composed that a measured value during the preliminary process and a measured value during the first process are compared so that the change of operating status is confirmed.