Research on Novel Multi-Way Hydraulic Quick Connector for Underwater Production System

The underwater hydraulic connector is one of the most important components of an underwater oil production system. The equipment is mainly used to transport oil, chemical reagents, and other high-pressure fluids. We developed a novel underwater hydraulic multi-way quick connector system (MQCS) that is able to realize simultaneous, rapid, and precise plugging and unplugging of 10 underwater pipelines. It can be widely used for connection between subsea oil production equipment. The MQCS consists of a fixed plate assembly that is fixed to the oil production equipment and a free plate assembly that is connected to the pipelines on the drilling platform. This study describes the structure and working principle of the MQCS in detail. In addition, the process of the elastic collet clamping the mandrel was studied. Based on the finite element analysis software Abaqus, we investigated how the key geometric parameters of the elastic collet influence the axial force that needs to be provided by the underwater robot. A prototype was built based on the simulation results. To verify the performance of MQCS, a high-pressure chamber test was conducted. The results show that MQCS can accurately connect 10 high-pressure lines (about 69 MPa) in a high-pressure chamber and there is no pressure drop for 3 h after docking.