Abstract: A coating apparatus with a spray head is provided for coating can bodies internally. The spray head is supplied with coating material through a feed line which passes through the seam welding machine for the container bodies. The combined spray and extraction head is also connected to a suction line which extracts excess coating material which has not been deposited on the internal walls of the container bodies, and returns it through the welding machine. In this way, the escape of coating material between the individual can bodies can largely be avoided, thus reducing contamination of equipment.