| Abstract |
With a turbo type fluid machine provided with a primary dry gas seal (9) and a secondary dry gas seal (10), abnormally in an amount of a working gas leaked from between a roating ring (7a, 7b)adapted to rotate with a rotor (4) and a stationary ring (8a, 8b) is detected by a pressure switch (14) and a flow meter (15) which are provided in a primary seal vent line (12) and meanwhile ,the working gas leaking from sealing surfaces (17) of a labyrinth seal (16) and the secondary dry gas seal , together with a purge gas purged to a space (18) from outside is discharge outside the machine from a flow passage (34) via a space (33) when abgnormality generates in the secondary dry gas seal, a control valve (19) provided in the purge gas line operates to secure a flow rate in the purge gas line, so that a flow rate detected by the flow meter provided in the purge gas line increases ,and thus abnormality in the secondary dry gas seal is detected. |