METHOD OF ABRASIVE-AIR TREATMENT OF SURFACE AND GUN INTENDED FOR ITS REALIZATION Russian patent published in 1999 - IPC

FIELD: cleaning of surface from different coatings and rust deposit. SUBSTANCE: method includes mixing of working substance with flow of compressed air and subsequent feeding of obtained mixture into jet for acceleration and discharge onto surface being treated. Compressed air is preliminarily expanded to level below atmospheric one and accelerated up to ultrasonic speed. At the same time working substance is supplied into accelerated air flow under pressure, in dense layer and at low speed of forward motion. Abrasive-air mixture is produced, and its acceleration is continued up to indicated full value of pressure which is higher than atmospheric level. Working substance flow rate is regulated by its supply pressure. Gun has body with branch pipes for delivery of materials and chamber. Chamber accommodates abrasive supply jet with critical cross section turning in to outlet jet. Internal surface of outlet jet is of tapered-cylindrical form. Abrasive feeding jet is made in form of injector. Is is installed coaxially in critical cross section with circular space relative to critical cross section of chamber. Plane of injector outlet hole coincides with critical cross section. EFFECT: enhanced efficiency and wear resistance. 6 cl, 2 dwg