To stably transfer a coating material while holding a satisfactory characteristic at a desired transfer speed regardless of the piping structure by regulating the transfer speed and/or transfer pressure of a force feed tool in the transfer of the coating material by sliding the force feed tool such as a pig inserted into a piping.

When a coating material 3 in a coating material tank 8 is transferred to a tank 17 through a pipeline 2, a valve 9 is opened, and a pump 10 is operated. When the feed of a prescribed quantity of the coating material 3 is completed, a pig 1 is ejected from a pig launcher 6 for the purpose of collecting the coating material 3 within the pipeline 2 by opening a valve 7 and working nitrogen gas of a prescribed pressure from a nitrogen feed part 5 to the pig 1. The pig 1 is advanced while pushing out the coating material 3 in the piping 2 by the pig 1. Sensors 12-14 are provided in the positions where the line resistance to the pig 1 is changed within the piping 2, and the nitrogen pressure from the nitrogen feed part 5 is changed according to the output of each sensor to control the transfer speed of the pig 1.