PURPOSE: To contrive to improve the yield ratio of a powdery rust preventive material and the inhibition of scattering with simplified equipment, by absorptively recovering a flipping part during spraying a hot-melt powdery rust preventive material.

CONSTITUTION: A hot-melt rust preventive material 2 in a tank is forcibly sent together with compressed air through piping 4 by a fan 3 for compressed transfer and sprayed through an applicator gun 5 onto a preheated part 6a to be coated. Said gun 5 has a top end comprising a nozzle 7 and a needle valve 8, and a cup 9 for covering the part 6a to be coated. Out of the material 2 sprayed onto the part 6a to be coated, a flipping part which has not been melt applied is absorptively recovered through piping 11 in a tank 12 for reuse by a suction fan 10, while inhibiting its scattering with the cup 9.