METHOD FOR RESTORING CAST IRON SLEEVES OF CYLINDERS OF AUTOMOBILE AND TRACTOR DIESEL ENGINES Russian patent published in 2000 - IPC

FIELD: machine engineering, namely, repairing machine parts, particularly, repairing worn inner cylindrical surfaces. SUBSTANCE: method comprises steps of creating continuous-successive temperature gradient along axis of part due to heating by high-frequency electric current circumferential local zone of sleeve wall and cooling it by water jets at process of moving part relative to heating and cooling sources in two passes; at first pass heating circumferential local zone of sleeve wall until temperature less than point Ac1 of phase conversion by 10-130 C; at second pass heating said zone until temperature more than point Ac1 by 30-80 C; then cooling in air until temperature less than point Ar1 by 30-50 C and performing cyclic heat treatment by multiple heating until temperature higher than point Ac1 by 30-80 C and cooling until temperature lower than point Ar1 by 30-50 C. EFFECT: enhanced quality of article due to increased service life of repaired cylinder sleeves. 2 dwg, 1 tbl, 1 ex