Abstract: A spraying nozzle of an installation for varnishing hollow bodies from their interiors and especially for varnishing metallic tubes or cans are connected with a spraying nozzle supporting device by a pivotal joint. In the driven out position of the supporting device when the nozzles are out of the hollow bodies, the spraying nozzles can be rotated through an angle and positioned in a tubular clearing device of a purification plant. The article to be sprayed and the spray nozzle are arranged so that the nozzles and the article may be moved relatively to cause the nozzle to enter into the article and move along its interior and spray the article interior as relative movement between the article and the nozzle is carried out and the nozzle and the article, and a cleaning apparatus are arranged so that the nozzle and the article can move relatively for drawing the nozzle out of the article and they can be shifted relatively through an angle and positioned into cooperative engagement with the cleaning apparatus.