How to clean galvanized surface?
How to clean galvanized surface?
1.Alkaline Solution Cleaning
Oil, grease and dirt can be removed by using an alkaline solution in the pH range of 11 to 12, butnot greater than 13. The solution can be applied through dipping, spraying or brushing. Ifbrushing, a soft-bristled nylon brush is recommended. If dipping or spraying, the solutiontemperature should be between 140 to 185 F / 60 to 85 C.For newly galvanized surfaces, a water-based emulsifier can be used to remove contaminants.After cleaning, thoroughly rinse the surface with clean, hot water and allow complete dryingbefore profiling or painting.
2.Ammonia Cleaning
A solution of 1 % to 2 % ammonia applied with a soft-bristled nylon brush also can be used,although this method typically is reserved for cleaning parts with ash residue sometimes leftbehind after the galvanizing process. After cleaning, thoroughly rinse the surface with clean, hotwater and allow complete drying before profiling or painting.
3.Solvent Cleaning
Mineral spirits, turpentine, high-flash naphtha and other typical cleaning solvents can be used,provided they are applied with lint-free rags or soft-bristled nylon brushes that are frequentlychanged to avoid re-spreading contaminants. (Solvents used for cleaning contain volatile organiccompounds and may affect total paint facility emissions. New non-VOC solvents are availablethat might achieve equivalent cleanliness.) Because mineral spirits and other solvents may leavebehind an oily deposit, surfaces should be thoroughly rinsed with clean, hot water and allowed todry before profiling or painting.Because some solvents may react differently with different paint systems, consult the paintmanufacturer for specific details about solvent/paint interactions.
4.Sealers Penetratings
Sealers are typically a two-part epoxy that forms a coating approximately two mils(50 microns) thick. They have been used as a surface treatment method on more difficult-tocleansurfaces such as partially weathered galvanized steel. Follow manufacturer directions forapplication; always use a topcoat over the sealer