As far as the washers are concerned, the recommended grade is the ASTM F436 hardened washer, type 1 or 3 depending on the type of bolt grade. Being that A325 type 3 bolts are made from weathering steel, the grade of nut used would be ASTM A563 Grade DH3 or C3. There are certain sizes that may be harder to find in the market place in a given grade, needing to be specially fabricated, in which case a grade substitution would be desired. There may also be situations where the project must follow guidelines requiring that the hardware be melted and manufactured in certain geographical areas. The reasoning behind one grade being preferred over another normally has to do with availability. These ASTM grades are all high strength and go through a heat treating process required to develop their mechanical characteristics. The recommended grade of nut for an ASTM A325 structural bolt is ASTM A563 Grade D, DH, or C. ASTM A194 2H is also an acceptable substitute.
0 Comments
Leave a Reply. |
AuthorWrite something about yourself. No need to be fancy, just an overview. ArchivesCategories |