Different from common sand dredger, the large sand dredger is bigger in shape. Therefore, there are some precautions in operation. Let's check them together. 
First, after starting two diesel engines of the sand dredger, its speed needs to be adjusted to required speed before releasing the big arm brake slowly. When sand in the bucket is over 2/3, operation below can be stopped and operation can be conducted again when it is up to 1/3. 
In case of 45° angle between the big arm and water surface, stopping is also needed and attention shall be paid to quantity of sand in the bucket because it decides forward speed. Certain flexibility shall also be kept for forward and backward. Release the traction rope in case of collapsed sand layer and stressed machine or pulling failure in forward process; strain the traction rope again after the ship retreats to possible excavation. 
A ship will encounter large stone or silt layer occasionally in forward process. Under the circumstance, a large sand dredger in particular will have intense vibration. In this case, the big sand dredging arm shall be lifted immediately and sand dredging can be conducted again after ducking the obstacle to prevent blind forward from damaging the equipment. 
During operation, pay close attention to the overall condition of the ship such as tightening of screws, filling of lubricating oil, chain pin, reducer and butt-joint disk. In case of flood season or work stop, the ship must be fastened in a reliable place to prevent it from being washed away and causing unnecessary loss.