An overall planning method for the launch and recovery system (LARS) of the mineral transportation equipment is given based on the mainstream deep-sea mining operation mode. Several key points are demonstrated and analyzed, focusing on the hook load, pipe tension force, mining pipe storage, transfer system types of the mining pipes, and transfer system types of the slurry pump and the relay station. The main technical parameters of the system are determined, and the arrangement of the derrick floor, moon pool and pipe rack region are planned. A general design scheme for the LARS of the mineral transportation equipment is then formed, which provides the design basis for the development of the deep-sea mining vessel.

The transient vibration of the crankshaft and the coupling characteristics of the bearing lubrication are studied in this paper. The overall finite element modeling of the crankshaft is established based on the finite beam element method. The lubrication characteristics of the dynamically loaded sliding bearing with consideration of the effect of journal misalignment are calculated by the finite difference method. A general and fast modeling and calculation method is proposed to achieve the parametric modeling of the overall system of piston-connecting rod-crankshaft-oil film-bearing. The dynamics of the crankshaft and the lubrication characteristics of the main bearing of the 4102 diesel engine are studied. The elastohydrodynamic lubrication of the crankshaft-bearing system is calculated and analyzed by using the dynamic deformation calculation method rather than the flexibility matrix method.

Mud system is an important part of the ocean drilling ship. The design of mud system often faces many problems, such as system equipment, difficult parameter matching, low drilling efficiency and safety, which directly affect the effect of the ocean drilling. Based on the demonstration of the mud requirements for the ocean drilling ship, this article analyzes the technical process of the high-pressure mud system, mud mixing system, mud storage and transfer system, mud process system, bulk storage and transfer system and high-pressure cementing system. The regional planning principles of the mud system are put forward to rationally plan the mud pump room, mud tank and mud processing area to form the arrangement plan of the mud system that is suitable for the target ship type. A reasonable selection of the mud equipment is made to form the configuration scheme of the mud system based on the functional requirements of the mud technical process. It can provide basis for the engineering design of the ship.

The characteristics of the critical equipment of the deep-sea mining vessel have been illustrated through the description of the mining operation process based on the large-scale scientific research project of the deep-sea mining vessels. The design of the strengthening structure is analyzed according to the appropriate specifications based on the critical equipment of A-frame crane and tower. Several optimization schemes are proposed for the optimization and comparison of the structural design in order to find out the optimization methods to reduce the local stress. It can provide references and methods for the structural strength design of ships.