Stainless Steel for Exterior Applications

This IMOA publication describes a selection process for stainless steel grades in external applications. A rating (scoring) process for site evaluation, design and proposed maintenance is described. Environments are divided into categories of rural, urban and industrial pollution. The effect of chlorides is then assessed by rating the site in terms of its proximity to coastal or marine salt exposure (de-icing salt) and local weather patterns. The combined design effects of surface finish, elevation (orientation) and natural rain washing are considered and finally the proposed maintenance (washing / cleaning) schedule. The total scores can then be used in the selection process. Grades considered in this rating process include 304 / 304L (1.4301 UNS S30400), 316 / 316L (1.4401 UNS S31600), 317L (1.4438 UNS S31703)and more highly alloyed grades including 2205 (1.4462 UNS S31803 32205) and 904L (1.4539 UNS S08904)

IMOA have designed the free interactive Stainless Steel Evaluation Software program to help with these issues: (Web site disclaimer | software disclaimer)

Go to the IMOA Website to download  the software which is PC and Mac compatible



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