ccording to the sealing requirement of the seabed sediment airtight sampler,a set of eccentrically set flap seal valve was designed,and the 3D geometrical model of the flap valve was established by using the 3D software Solidworks.The changes of the stress and strain of the valve body and valve cover of the flap sealing valve were analyze under different eccentric angles by using the finite element analysis software ANSYS.The results show that the stress and strain of the valve body and the valve cover are increased with the increasing of the eccentric angle of the flap sealing valve,while the weight of the corresponding flap seal valve is gradually decreased.By choosing the optimal eccentric angle,the weight of the flap sealing valve was minimized under the premise that the stress on the flap valve is less than the allowable stress of the material.The sealing performance testing system of the flap seal valve was designed,and the flap seal valve sealing performance testing experiment was carried out.The experimental results verified the feasibility and rationality of the flap valve seal design.