TM-9-2350-311-34-1
HULL, POWERPLANT, DRIVE CONTROLS, TRACKS, SUSPENSION, AND ASSOCIATED COMPONENTS: HOWITZER, MEDIUM, SELF-PROPELLED, 155MM
TECHNICAL MANUAL; DIRECT SUPPORT AND GENERAL SUPPORT MAINTENANCE MANUAL
SEPTEMBER 1994
TM-9-2350-311-34-1 - Page 319 of 352
TM 9-2350-311-34-1
E-5 FASTENER GRADE
In addition to thread type classification, threaded fasteners are also classified by material. The most familiar fastener
classification system is the SAE grading system (Table E-4).
TABLE E-4 SAE SCREW AND BOLT MARKINGS
SCREWS
BOLTS
SAE grade 2
SAE grade 6
No marking
Four radial dashes
90° apart
SAE grade 3
Two radial dashes
SAE grade 7
180° apart
Five radial dashes
72° apart
SAE grade 5
Three radial dashes
SAE grade 8
120° apart
Six radial dashes
60° apart
Markings on Hex Locknuts
Grade A — no marks
Grade B — three marks
Grade C — six marks
Grade A — no notches
Grade B — one notch
Grade C — two notches
Grade A — no mark
Grade B — letter B
Grade C — letter C
E-5/(E-5 blank)
Back to Top
