A.0.25% B.0.45% C.0.55% D.0.70%
A.75° B.60° C.45° D.30°
A.不必修理 B.必須補(bǔ)焊 C.挖補(bǔ)修理 D.用砂輪把裂紋磨掉,并與金屬表面圓滑過(guò)渡即可