Cylinder body device capable of switching forming size

The invention discloses a cylinder body device capable of switching forming sizes. The cylinder body device is simple in structure, convenient to install, easy to maintain and convenient to replace due to modular design. The device comprises a forming cylinder piston, an annular cylinder body assembly, an anti-tilting device and a piston lifting mechanism. When the equipment is used for sintering workpieces with different sizes, in order to prevent waste of redundant powder, different annular cylinder body assemblies and forming cylinder pistons are matched and replaced according to the workpieces with different sizes. When workpieces of different sizes are printed, only the piston of the forming cylinder and the annular cylinder body assembly need to be replaced. Therefore, the selective laser melting additive manufacturing equipment can freely replace the forming cylinder body according to the size of a part to be formed, and is used for adaptively adjusting the forming breadth of the equipment when the siz