| 摘要 |
PROBLEM TO BE SOLVED: To provide a lapping tool not damaging the polished surface of a workpiece. SOLUTION: In this lapping tool 10, the polished surface 14a rotating relative to a valve seat face 30 is fitted closely to the valve seat face 30 through abrasive agent. Annular grooves 14c concentric to the rotating center of the polished surface 14a are formed in the polished surface 14a. |
