3 1/4-4 A563 GRADE A HEAVY HEX NUT

Grade A requires no material marking

Mechanical PropertiesGrade A

1. 1. To determine nut proof load in pounds, multiply the appropriate nut proof load stress by the tensile stress area of the thread.
2. 2. Non-zinc-coated nuts are nuts intended for use with externally threaded fasteners which have a plain (nonplated or noncoated) finish or have a plating or coating of insufficient thickness to necessitate overtapping the nut thread to provide assemblability. Zinc-coated nuts are nuts intended for use with externally threaded fasteners which are hot-dip zinc-coated, mechanically zinc-coated, or have a plating or coating of sufficient thickness to necessitate overtapping the nut thread to provide assemblability.

Chemical PropertiesGrade A

1. 1. For Grade A a sulfur content of 0.23 % max is acceptable with the purchasers approval.

Dimensional SpecificationsGrade A

1. All dimensions are in inches.