SECTION 8 -- SPECIFICATIONS
8--22
MINIMUM HARDWARE TIGHTENING TORQUES
IN FOOT--POUNDS (NEWTON METERS) FOR NORMAL ASSEMBLY APPLICATIONS
INCH HARDWARE AND LOCKNUTS
SAE GRADE 2 SAE GRADE 5 SAE GRADE 8 LOCKNUTS
NOMINAL UNPLATED PLATED UNPLATED PLATED UNPLATED PLATED GR.B GR.C
SIZE or w/ZnCr or w/ZnCr or w/ZnCr w/GR5 w/GR8
PLATED PLATED PLATED BOLT BOLT
SILVER GOLD SILVER GOLD SILVER GOLD
1/4 55* (6.2) 72* (8.1) 86* (9.7) 112* (13) 121* (14) 157* (18) 61* (6.9) 86* (9.8)
5/16 115* (13) 149* (17) 178* (20) 229* (26) 250* (28) 324* (37) 125* (14) 176* (20)
3/8 17 (23) 22 (30) 26 (35) 34 (46) 37 (50) 48 (65) 19 (26) 26 (35)
7/16 27 (37) 35 (47) 42 (57) 54 (73) 59 (80) 77 (104) 30 (41) 42 (57)
1/2 42 (57) 54 (73) 64 (87) 83 (113) 91 (123) 117 (159) 45 (61) 64 (88)
9/16 60 (81) 77 (104) 92 (125) 120 (163) 130 (176) 169 (229) 65 (88) 92 (125)
5/8 83 (112) 107 (145) 128 (174) 165 (224) 180 (244) 233 (316) 90 (122) 127 (172)
3/4 146 (198) 189 (256) 226 (306) 293 (397) 319 (432) 413 (560) 160 (217) 226 (305)
7/8 142 (193) 183 (248) 365 (495) 473 (641) 515 (698) 667 (904) 258 (350) 364 (494)
1.0 213 (289) 275 (373) 547 (742) 708 (960) 773 (1048) 1000 (1356) 386 (523) 545 (739)
NOTE: Torque values shown with * are inch pounds.
IDENTIFICATION
CAP SCREWS AND CARRIAGE BOLTS
SAE
GRADE 2
SAE
GRADE 5
SAE
GRADE 8
REGULAR
NUTS
SAE
GRADE 5
HEX NUTS
SAE
GRADE 8
NUTS
LOCKNUTS
GRADE IDENTIFICATION
GRADE IDENTIFICATION
GRADE A NO MARK
GRADE B LETTER B
GRADE C LETTER C
GRADE A NO MARKS
GRADE B THREE MARKS
GRADE C SIX MARKS
MARKS NEED NOT BE LOCATED
AT CORNERS
GRADE IDENTIFICATION
GRADE A NO NOTCHES
GRADE B O NE CIRCUMFRETIAL NOTCH
GRADE C TWO CIRCUMFRENTIAL NOTCHES