Abstract: A gas leak determining method for a multi-stage compressor including: a first compressing unit that compresses a gas; and a second compressing unit that further compresses the gas compressed by the first compressing unit includes: a step of calculating a proportion of discharge pressure from the second compressing unit to discharge pressure from the first compressing unit or suction pressure into the second compressing unit; and a step of determining that a gas is leaking from the second compressing unit when the proportion becomes equal to or less than a set value.

Abstract: An abnormality treatment apparatus includes: a sensor which outputs a signal upon detecting an event caused by contact of a rotor of a rotating machine during rotation of the rotor; and a control unit which executes at least one of rotation number control of reducing the number of rotations of the rotor step by step, liquid injection control of injecting liquid into a housing chamber of the rotor step by step, and pressure control of lowering a discharge pressure of the rotating machine step by step based on reception of the signal output from the sensor.

Abstract: An abnormality treatment apparatus includes: a sensor which outputs a signal upon detecting an event caused by contact of a rotor of a rotating machine during rotation of the rotor; and a control unit which executes at least one of rotation number control of reducing the number of rotations of the rotor step by step, liquid injection control of injecting liquid into a housing chamber of the rotor step by step, and pressure control of lowering a discharge pressure of the rotating machine step by step based on reception of the signal output from the sensor.

Abstract: A gas leak determining method for a multi-stage compressor including: a first compressing unit that compresses a gas; and a second compressing unit that further compresses the gas compressed by the first compressing unit includes: a step of calculating a proportion of discharge pressure from the second compressing unit to discharge pressure from the first compressing unit or suction pressure into the second compressing unit; and a step of determining that a gas is leaking from the second compressing unit when the proportion becomes equal to or less than a set value.

Abstract: A rotating machine abnormality detection device and a rotating machine abnormality detection method according to the present invention are designed to detect an abnormality in a rotating machine including a rotary member rotatable about a predetermined axis, and detect an initial abnormality in the rotating machine based on first measurement data obtained by measuring a vibration in an ultrasonic wave band caused by the rotary member. A rotating machine according to the present invention includes the rotating machine abnormality detection device.

Abstract: A rotating machine abnormality diagnosing apparatus for diagnosing an abnormality in a rotating machine includes: an analyzing part which performs a time-frequency analysis to a signal S representing intensity and time relationship of an elastic wave generating in the rotating machine; an extracting part which extracts second data representing intensity and time relationship of a predetermined frequency component from first data obtained by the time-frequency analysis; and a determining part which determines that a first rotor and a second rotor are in contact with each other when the second data contains intensity variation having a cycle represented by T1×b=T2×a, in which a rotational cycle of the first rotor is denoted by T1, a rotational cycle of the second rotor is denoted by T2, and a ratio of a number of protrusions to a number of recesses is denoted by a:b.

Abstract: A rotating machine abnormality detection device and a rotating machine abnormality detection method according to the present invention are designed to detect an abnormality in a rotating machine including a rotary member rotatable about a predetermined axis, and detect an initial abnormality in the rotating machine based on first measurement data obtained by measuring a vibration in an ultrasonic wave band caused by the rotary member. A rotating machine according to the present invention includes the rotating machine abnormality detection device.

Abstract: A rotating machine abnormality diagnosing apparatus for diagnosing an abnormality in a rotating machine includes: an analyzing part which performs a time-frequency analysis to a signal S representing intensity and time relationship of an elastic wave generating in the rotating machine; an extracting part which extracts second data representing intensity and time relationship of a predetermined frequency component from first data obtained by the time-frequency analysis; and a determining part which determines that a first rotor and a second rotor are in contact with each other when the second data contains intensity variation having a cycle represented by T1×b=T2×a, in which a rotational cycle of the first rotor is denoted by T1, a rotational cycle of the second rotor is denoted by T2, and a ratio of a number of protrusions to a number of recesses is denoted by a:b.