After starting the dredge engine, let it idle for about 10 minutes. Once the water temperature, oil temperature, and oil pressure reach the specified requirements, production can begin. (Note: Refer to the dredge's engine manual for specific requirements.) When the engine is ready to drive the sand pump, and an operator is in the control room, first turn on the 24V main power switch on the dredge's control panel. Then, use the dredge's gantry winch to lower the gantry and suction pipe, submerging the cutterhead in the water, and then start the flushing pump. Next, engage the gearbox and sand pump using the clutch switch on the control panel so that the engine drives the gearbox to power the sand pump. Slowly increase the engine speed to the specified RPM. However, the gearbox engagement speed is limited; the engine is not allowed to engage at high speeds. Once the sand pump is drawing water and water is flowing normally from the discharge pipe outlet, the cutterhead can be started, and the dredge can begin production by moving left and right. Note: When the dredge is performing a sweeping motion during production, the spud poles must not be simultaneously inserted into the mud. This is not permitted during operation. If the sand pump needs to be stopped during dredging, the gearbox must be disengaged from the sand pump. The dredge engine speed must be reduced to the specified speed before disengaging the gearbox.
During dredging operations, engine room personnel should observe the engine room conditions through smelling, listening, looking, and touching. They should check for unusual odors, listen for abnormal noises, and observe whether the engine monitoring instruments are functioning correctly. They should also check for oil leaks in the hydraulic system, water leaks in the cooling system, and any leaks (water, oil, or air) from the engine. They should also feel the temperature and vibration of moving parts.
Deck operators should also observe the conditions above deck through smelling, listening, and looking. They should check for unusual odors, listen for abnormal sounds, and observe whether the monitoring instruments on the dredge's control panel are functioning correctly, as well as the movements of passing vessels. They should also check for oil leaks in the hydraulic system pipes and underwater pipes on the deck. When the dredger is not in operation, before stopping the engine, the cutter head should be lifted out of the sand layer using the gantry winch and kept submerged in the water for a period while continuing to pump water. This ensures that the entire sand discharge pipeline of the dredger is free of sand. Then, the engine speed is reduced to disengage the sand pump, and the gantry is lifted out of the water using the gantry winch and secured with safety devices. The engine can then be stopped, the seabed valve and other valves (control components) closed, the power supply cut off, and the windows and doors closed.
