多项选择题
A.VN2=0.005rnol/(L¡¤s) B.VH2=0.015rnol/(L¡¤s) C.VNH3=0.01rnol/(L¡¤s) D.VNH3=0.02rnol/(L¡¤s)
A.炉管不发生超温 B.炉管不发生超压 C.保证炉膛温度下降平稳 D.炉膛温度均匀
A.发生氢腐蚀 B.焊接技术缺陷 C.发生金属疲劳 D.材质缺陷