Abstract: Means is disclosed for washing the inside of a pelletizing machine containing a bag filter which is capable of being raised and lowered within the body of the machine. A vertically movable, upright means to spray washing liquid in three dimensions is provided above the bag filter. A horizontally movable spraying means is provided below the bag filter. This horizontal spraying means can be retracted from inside the pelletizing machine during pelletizing operations, but is capable of spraying washing liquid upwardly into the open end of the bag filter during washing operations.

Abstract: Each of the washing units A and B comprises an openable and closable pinch valve unit 4 branchwise connected to a pipeline C, an autofeeder unit 5 for controlling the feed for advance and retraction movement of a high pressure hose 6 having rotatable nozzle unit connected to the front end thereof, and a hose reel unit 7 for winding and unwinding the high pressure hose. During washing operation, the nozzle unit enters the pipeline C through the pinch valve unit 4 now opened to wash the inner surface of the pipeline. During nonwashing period, the nozzle unit is moved rearward and completely isolated from the pipeline by the pinch valve unit 4 now closed. Therefore, the washing units A and B are completely separated from the pipeline C during nonwashing period.