LIGHTWEIGHT ROTOGRAVURE PRINTING CYLINDER
Rotogravure cylinders used for printing on packaging materials based on the transfer of ink onto the packaging material from the printing cylinder surface with a printing technique. The lightweight rotogravure printing cylinders developed are not heavy which prevent the factors which pose an ergonomic risk in terms of occupational health and safety and also cause an increase in logistics costs. For this purpose, the wall thickness of the steel body of the cylinder is decreased.
1 . A lightweight rotogravure printing cylinder comprising:
at least one body which has a hollow cylindrical form and inlets at both ends of the lateral surface of the cylindrical form that are open so as to allow access to the inner volume, and wherein
at least one cover which enables to close the open inlets of the cylindrical body and to form a closed cylindrical form,
at least one shaft opening that allows grasping the shaft which enables the cylindrical body to be placed on the printing machine and rotational movement to be transferred therethrough, when it is passed through the center of the cylindrical body; and
at least one rib in the form of a circular plate which is spaced apart along the length of the cylindrical body extending between the covers, and enables the middle section of the cylindrical body remaining between the at least one cover to be supported from its inner surface, and has a shaft opening of a size that allows the shaft to pass through the center thereof.
2 . The lightweight rotogravure printing cylinder according to claim 1 , wherein the wall thickness of the steel plate material used to form the body is 3.5-7.5 mm.
3 . The lightweight rotogravure printing cylinder according to claim 1 , wherein the distance (L) between two consecutive ribs is in the range of minimum 1 cylinder diameter (D) and maximum 2 cylinder diameters (D).
4 . The lightweight rotogravure printing cylinder according to claim 1 , wherein ribs are positioned such that there will be at least 2 of them for each 1 meter of length along the length of the cylindrical body.
5 . The lightweight rotogravure printing cylinder according to claim 1 , wherein at least 3 ribs are positioned at equal intervals inside the cylindrical body.
6 . The lightweight rotogravure printing cylinder according to claim 1 , wherein the wall thickness of the rib enabling the cylindrical body to be supported from its inner surface is a maximum of 5 mm.
7 . The lightweight rotogravure printing cylinder according to claim 1 , wherein ribs are welded to the inner walls of the cylindrical body with a circumferential welding method (Mig-Mag method).