A.酸洗 B.水沖洗 C.蒸汽吹洗 D.噴砂
A.80% B.90% C.95% D.98%
A.腐蝕部位局部超溫 B.停用保護(hù)不當(dāng) C.蒸汽的品質(zhì)差 D.過(guò)熱器較為污臟