| 摘要 |
A pressure vessel sight glass, especially a tempered glass, is protected against the corrosive attack of normally alkaline, boiler feed water heated up to 300 DEG C., by providing the sight glass with a metallic oxide coating consisting essentially of SnO2, optionally combined with Cr2O3. The coating is preferably applied as a sprayed solution of soluble salt convertible to the oxide. |
