Grain Systems Tanks PNEG-4072 - Manual (Page 25)

Chapter 3: Hardware Requirements
Identifying Bolt Grades
Bolts are identified by grade (or hardness), the grade can be identified by the markings on the head of the
bolt. These markings will be in the form of slash marks and patterns. Use the following as a guide to deter-
mine the correct bolt grade.
CAUTION
Under no condition shall any other bolts be substituted for those supplied by GSI.
Grade 2 Bolts
Grade 2 bolts are designated with a plain head and are not used in GSI grain bins.
Grade 5 Bolts
Grade 5 bolts are designated by three slash marks on the head. All 5/16 inch diameter bolts
are to be grade 5 or higher.
Grade 8 Bolts
Grade 8 bolts are designated by six slash marks evenly spaced out around the head of the
bolt. All 3/8, 7/16, and 1/2 inch diameter bolts are to be grade 8 or grade 8.2.
Grade 8.2 Bolts
Grade 8.2 bolts are designated by six slash marks on the head in a sunrise pattern. All 3/8,
7/16, and 1/2 inch diameter bolts are to be grade 8 or grade 8.2.
NOTE: Refer to 2.66" commercial tank bolting requirements for complete bolt usage.
Pneg-4072 72 Ft Diameter 40-Series Bin 25