In view of the problem of insufficient dredging depth of cutter suction dredger and the requirements of environmental protection construction,the cutter suction dredger is adapted to be reformed,specifically replacing the cutter excavating equipment at the front end of cutter suction dredger with environmental protection dredging equipment,which realizes the environmental protection dredging function of cutter suction dredger.In order to increase the flexibility of the dredging equipment operation performance,a new type of dredging equipment is developed which is located between the bridge and desilting suction head.According to the three working conditions of horizontal suspension,36 m excavation depth and 40 m excavation depth,the strength of key components of dredging equipment is analyzed.The results show that the maximum stress of the key components is 84.2 MPa and the maximum deformation is 2.5 mm,which meets the requirements of strength and rigidity,and the optimized key components meet the construction requirements.