What are the shutdown procedures for wear-resistant high-pressure centrifugal fans?

What are the shutdown procedures for wear-resistant high-pressure centrifugal fans?

When commissioning a wear-resistant high-pressure centrifugal fan, a phased approach is required to ensure the fan operates correctly. When the wear-resistant high-pressure centrifugal fan is not in operation and needs to be shut down, a phased approach is also required. The shutdown of a wear-resistant high-pressure centrifugal fan can be categorised as either an emergency shutdown or a normal shutdown. Operating the wear-resistant high-pressure centrifugal fan: 1. Emergency shutdown: During the trial operation of the unit, an emergency shutdown must be performed immediately if any of the following situations occur. The emergency shutdown procedure involves pressing the stop button on the main motor; inspection and maintenance should be carried out after shutdown. 1. The wear-resistant high-pressure centrifugal fan suddenly vibrates violently, exceeding the trigger value. b. Scratching or abnormal friction noises are heard inside the housing. c. Smoke is emitted from bearings or seals, or the temperature of a specific bearing rises sharply to the alarm value. d. Oil pressure falls below the alarm value and cannot be restored to normal. e. The fuel tank level is low, with signs of running dry. f. The axial displacement value continues to increase, reaching the alarm value. 2. Normal Shutdown: Follow the steps below to perform a normal shutdown of the unit. a. Slowly open the exhaust valve (or outlet bypass valve), then slowly close the exhaust valve. b. Gradually reduce the air inlet valve to 20–25°. c. Press the stop button, paying attention to any abnormalities during the shutdown process. d. Allow the unit to stand for 5–10 minutes, or until the bearing temperature falls below 45°C, before stopping the oil supply. If a floating ring seal is fitted, the seal oil pump must continue to supply oil until the temperature of the valve body falls below 80°C. Following the introduction of these two shutdown methods for wear-resistant high-pressure centrifugal fans, not only are strict requirements in place, but specific measures must also be taken when the machine is not in operation or during shutdown.