PURPOSE: To bring the effect of a soot blower into wider range, by oscillating an injection nozzle by rotating a rotary shaft, inserted into the inside of an injection pipe, being interlocked with the movement of an injection pipe.

CONSTITUTION: A soot blowing medium is fed into an injection pipe 2 through a soot-blowing medium feed pipe 11 by opening a valve for a feeding source of soot blowing medium, and is injected into a duct from an injection nozzle 7. The injection pipe 2 is moved in parallel, being pulled by a chain 13. A pinion 15 is revolved by engaging with a rack 14, being interlocked with the movement of an injection pipe 2. A rotary shaft 29 is rotated by revolution of the pinion 15, and an injection nozzle 7 is oscillated by the horizontal movement of a connecting rod 28, interlocked with a guide groove 30. With such an arrangement, the effective range of a soot blower is enlarged, by the multiplied effect of a movement of injection pipe and an oscillation of injection nozzle. The number of nozzles is decreased, by the amount corresponding to the increased effect of a soot blower, as a result, the consumption of medium can be decreased, in the titled soot blower.