Method for emptying a supply line for coating units

A supply line (3) for supplying or charging of coating application devices of a coating system, in particular the paint application device of a painting system with coating means such as, for example, paint, from one or a plurality of coating means containers or reservoirs, wherein the supply line has a valve device, which makes it possible that the coating means volume present in the supply line (3) is displaced counter to the direction of flow back into a coating means container or into a supply line, and the supply line (3) consists of a flexible, radially compressible hose (3), and this hose (3) is surrounded by a jacket hose or jacket tube (2), wherein the interstitial space (7) between the flexible hose (3) and the jacket hose or jacket tube (2) is impinged with a pressure medium by means of at least one valve device (4) connected with the interstitial space (7), and the supply line (3) can be compressed radially by application of a pressure medium on the external periphery, so that the coating means passage cross-section is minimized and any coating means volume present in the supply line is forced out, and wherein the valve device (4) for impinging the interstitial space (7) between the jacket hose or jacket tube (2) and supply line (3) relative to the direction of flow of the coating means is arranged in the zone of the end of the supply line, and impinging of the interstitial space (7) is done with a pressure medium against the direction of flow of the coating means at the time of application of the coating means.