Ship main propulsion device common base and installation method

The invention relates to a common base of a ship main propulsion device and an installation method, a first platform is provided with an upper panel and a lower panel, the upper panel is used for installing a power output system of the ship main propulsion device, and the lower panel is used for installing a vibration isolator; the second platform is provided with a panel for mounting the middle bracket, and an adjusting cushion block for supporting the middle bracket is mounted on the panel; the planeness of the upper panel and the panel does not exceed 0.02 mm, and the roughness of the upper panel and the panel is Ra3.2; the planeness of the lower panel does not exceed 0.05 mm, and the roughness of the lower panel is Ra12.5. S1, a power output system is installed on an upper panel of the first platform; during installation, the power output system, the middle support, the vibration isolator and the elastic coupler are sequentially installed; a main propulsion device base is welded and installed on a ship bo