摘要 |
A screw fluid machine has a first non-contact seal, a second non-contact seal and a lip seal disposed between a rotor chamber and a bearing for a rotor shaft located on the high pressure side, and in this order from the rotor chamber side. It includes a pressurized communicating channel for introducing high-pressure target gas into a pressurized space formed between the first and second non-contact seals, a pressurized pressure detecting device for detecting the pressure of the pressurized space, and an alarm device for generating an alarm when a value detected by the pressurized pressure detecting device falls out of a predefined range of pressurized pressures. The screw fluid machine is capable of detecting or predicting a condition of the shaft sealing device and accurately and reliably reporting the detected condition to an operator. |