METHOD FOR RESTORING SURFACES OF HOLLOW CYLINDERS Russian patent published in 1998 - IPC

FIELD: restoration of worn inner surfaces of parts such as sleeves, possibly in automobile and tractor construction at repairing liners of cylinders of automobile and tractor engines. SUBSTANCE: method comprises steps of placing worn liner to holder made of material with high linear expansion factor such as predetermined kind of steel and embracing worn part along its outer diameter; placing inner surface of liner into protective powder medium consisting, for example of technical boron carbide - 88%, borax - 5%, titanium - 7%; heating it at least up to 950 C and soaking at that temperature for 0.5-2 h; cooling inner surface of liner by compressed air jet directed normally relative to part axis; cooling outer surface of liner due to naturally cooling holder embracing liner along its outer surface. EFFECT: enhanced efficiency. 2 dwg