Design and performance study on adaptive sealing of a dry cabin for maintenance of submarine pipeline

The underwater dry maintenance method based on a dry cabin can achieve the same maintenance quality provided on land. The establishment of a reliable seal between the dry cabin and the pipe is a prerequisite for the formation of a dry environment. In this paper, an airbag is proposed as the means to seal the dry cabin. ABAQUS finite element software was used to study the influence of the physical characteristics of the airbag on deformation characteristics and sealing performance. We also studied the adaptive sealing mechanism of the airbag under the time-varying gap condition. The simulation results show that the peak contact stress of the airbag is close to the gas pressure, so the hardness and thickness of the airbag have little effect on it. Under time-varying gap conditions, the required inflation pressure increases with the size of the gap. The simulated relationship between the gap and the inflation pressure can be referred to in order to guide the control of the air pressure of the airbag during actual operation. Finally, the similarity between the test results and simulation results demonstrates the accuracy of the simulation results.