Abstract: Disclosed is a chucking device for chucking a drum to keep it vertical while the drum is immersed in a coating liquid to be coated with the coating liquid. The chucking device comprises upper and lower pressure members having tapered peripheral surfaces at their ends facing each other. An annular elastic member is fitted between the tapered peripheral surfaces. The pressure members are constantly urged toward each other. When chucking a drum, the lower pressure member is moved away from the upper pressure member by means of compressed air so as to contract the elastic member, thereby allowing the pressure members and the elastic member to be inserted into the drum. Then, the compressed air is released, allowing the pressure members to contact each other. This causes the elastic member to be pressed outward by the tapered peripheral surfaces to tightly contact the inner surface of the drum.

Abstract: A flange for a drum is disclosed. The flange is mounted on one end of the drum to rotate together with it, and comprises a hole passing therethrough along the axis of rotation to receive a rotation shaft therethrough, so that the flange can rotate together with the rotation shaft. The hole comprises an inside portion having an oblong cross section and an outside portion having a perfectly circular cross section, the inside portion being located toward the drum, and the outside portion being open toward the outside. One end portion of the rotation shaft has an oblong cross section and is securely fitted in the oblong portion of the hole. When the drum is to be tested for concentricity with the rotation shaft, a conical rotation pin is inserted into the circular portion of the hole so that the flange can be rotated concentrically with, and together with the conical rotation pin.