12 Point Flange Bolt: Dimensions & Specifications

12 Point Flange Screw Drawing 

12 Point Flange Bolt (ANSI B1.1 UNC, UNF)

Nominal
Size of Screw

Click on Size to Shop Products

 Body Diameter
- Max Equal
to Nom Size -
(E)

Flange
Diameter
(B)

 Width
Across
Flats
(F)		 Width Across
Corners
(G)		 Head Height
(H)		 Wrench
Height
(K)

Flange
Thickness
(U)

Thread Length
(LT)
Max Min Max Min Max Min Min Max Min Min Min
1/4 0.2500 0.2435 0.375 0.365 0.252 0.244 0.278 0.260 0.15 0.058 1.000
5/16 0.3125 0.3053 0.469 0.457 0.315 0.306 0.348 0.312 0.18 0.074 1.125
3/8 0.3750 0.3678 0.562 0.550 0.377 0.368 0.420 0.375 0.21 0.095 1.250
7/16 0.4375 0.4294 0.656 0.642 0.438 0.429 0.489 0.438 0.26 0.109 1.375
1/2 0.5000 0.4919 0.750 0.735 0.502 0.493 0.562 0.500 0.29 0.129 1.500
5/8 0.6250 0.6163 0.938 0.921 0.627 0.618 0.705 0.625 0.36 0.166 1.750
3/4 0.7500 0.7406 1.125 1.107 0.752 0.743 0.847 0.750 0.44 0.200 2.000
7/8 0.8750 0.8647 1.312 1.293 0.875  0.866 N/A  0.875 0.51 0.234 2.250
1 1.0000 0.9886 1.500 1.479 1.000  0.991 N/A  1.000 0.60 0.268 2.500
1 1/8 1.1250 1.1090 1.688 1.665  1.125   1.115 N/A  1.125 0.66 0.310 2.750 
1 1/4 1.2500 1.2240 1.875 1.852  1.252   1.240 N/A  1.250 0.73 0.350 3.000 
1 1/2 1.5000 1.4820 2.250 2.224  1.502   1.489 N/A  1.500 0.87 0.433 3.250 

 

IFI 115
Material: Alloy Steel AISI 4135/4140
Wedge Tensile: Min 170,000 psi
Core Hardness: HRC 37~43
Screw Threads: ANSI B1.1 UNC, UNF
Class of Thread: 1/4 through 3/4, 2A, 3A