INCONEL 625 BOLTS - UNS N06625 / W.NR. 2.4856
■ ASME B18.2.1 Heavy Hex Bolt Dimensions (Inches)
| NOMINAL SIZE |
BODY DIA (Max) |
WIDTH ACROSS FLATS (Basic) |
WIDTH ACROSS CORNERS (Max) |
HEAD HEIGHT (Basic) |
| 1/2" |
0.515 |
7/8 |
1.010 |
11/32 |
| 5/8" |
0.642 |
1-1/16 |
1.227 |
27/64 |
| 3/4" |
0.768 |
1-1/4 |
1.443 |
1/2 |
| 7/8" |
0.895 |
1-7/16 |
1.660 |
37/64 |
| 1" |
1.022 |
1-5/8 |
1.876 |
43/64 |
| 1-1/8" |
1.149 |
1-13/16 |
2.093 |
3/4 |
| 1-1/4" |
1.277 |
2 |
2.309 |
27/32 |
| 1-1/2" |
1.531 |
2-3/8 |
2.742 |
1 |
| 2" |
2.039 |
3-1/8 |
3.608 |
1-11/32 |
Engineering Note: Heavy Hex Bolts are universally specified for high-pressure pipeline flanges and petrochemical vessels. The robust geometry prevents local yielding or crushing of softer parent flange materials under extreme clamp loads.
■ Metric DIN 931 / DIN 933 Hexagon Head Bolts (mm)
| THREAD SIZE (d1) |
NOMINAL PITCH |
WIDTH ACROSS FLATS |
HEAD HEIGHT |
| M6 |
1.00 |
10.0 mm |
4.0 mm |
| M8 |
1.25 |
13.0 mm |
5.3 mm |
| M10 |
1.50 |
17.0 mm |
6.4 mm |
| M12 |
1.75 |
19.0 mm |
7.5 mm |
| M16 |
2.00 |
24.0 mm |
10.0 mm |
| M20 |
2.50 |
30.0 mm |
12.5 mm |
| M24 |
3.00 |
36.0 mm |
15.0 mm |
| M30 |
3.50 |
46.0 mm |
18.7 mm |
| M36 |
4.00 |
55.0 mm |
22.5 mm |
■ DIN 912 Socket Head Cap Screws (mm)
| THREAD SIZE (D) |
NOMINAL PITCH |
HEAD DIA (Max) |
HEAD HEIGHT (Max) |
HEX KEY SIZE (s) |
| M4 |
0.70 |
7.00 mm |
4.00 mm |
3.0 mm |
| M6 |
1.00 |
10.00 mm |
6.00 mm |
5.0 mm |
| M8 |
1.25 |
13.00 mm |
8.00 mm |
6.0 mm |
| M10 |
1.50 |
16.00 mm |
10.00 mm |
8.0 mm |
| M12 |
1.75 |
18.00 mm |
12.00 mm |
10.0 mm |
| M16 |
2.00 |
24.00 mm |
16.00 mm |
14.0 mm |
| M20 |
2.50 |
30.00 mm |
20.00 mm |
17.0 mm |
| M24 |
3.00 |
36.00 mm |
24.00 mm |
19.0 mm |
■ Torque Specifications (Imperial ASTM B446 Minimums)
| BOLT SIZE & TPI (UNC) |
CLAMP LOAD TARGET (lbf) |
INSTALLATION TORQUE (Dry K=0.22) (ft-lbf) |
INSTALLATION TORQUE (Lubricated K=0.13) (ft-lbf) |
| 1/2" - 13 |
5,874.7 |
53.9 |
31.8 |
| 5/8" - 11 |
9,356.4 |
107.2 |
63.4 |
| 3/4" - 10 |
13,827.6 |
190.1 |
112.3 |
| 7/8" - 9 |
19,126.8 |
306.8 |
181.3 |
| 1" - 8 (UN) |
25,088.4 |
460.0 |
271.8 |
| 1-1/4" - 7 |
40,116.6 |
919.3 |
543.2 |
| 1-1/2" - 6 |
58,167.0 |
1,599.6 |
945.2 |
■ Bolt-Specific Technical Specifications
| Material & Matrix |
Inconel 625 (UNS N06625). Relies on solid-solution stiffening (Molybdenum and Niobium) within its face-centered cubic nickel-chromium matrix. |
| Metallurgical Grades |
- Grade 1 (Soft Annealed): Optimum for wet-corrosion, marine environments, and operations < 1150°F (621°C). Yields ~60-95 ksi.
- Grade 2 (Solution Annealed): Mandatory for high-stress aerospace/petrochemical applications > 1500°F (815°C) to maximize creep resistance.
|
| Manufacturing Standards |
ASTM F468 (Fasteners), ASTM B446 (Precursor Rod/Bar Stock). |
| Tribology & Installation |
Inconel 625 bolts have poor thermal conductivity, making them highly susceptible to thread galling if rapidly installed. Dry installation is strictly prohibited. Use Molybdenum Disulfide (MoS2) or marine-grade pastes to drop the K-factor to ~0.13. Do NOT use high-speed impact tools. |
| Corrosion Resistance |
Virtually immune to chloride-induced stress-corrosion cracking (SCC) and localized crevice/pitting corrosion. Withstands severe thermal shock and oxidation up to 1800°F. |
