3/4" Grade 2 Torque Specification

Torque Values by Surface Condition

Stress area: 0.334 in² · Proof load: 18,370 lbs · Clamp load (75%): 13,778 lbs

Surface Condition	K Factor	ft·lbs	N·m	in·lbs	kgf·cm
Plain/Dry	0.2	172.2	233.5	2066.4	2381.0
Oiled	0.15	129.2	175.2	1550.4	1786.5
Zinc Plated	0.18	155.0	210.2	1860.0	2143.5
Waxed	0.1	86.1	116.7	1033.2	1190.0
MoS₂	0.12	103.3	140.1	1239.6	1428.6
Galvanized	0.25	215.3	291.9	2583.6	2976.6

Stress area: 0.373 in² · Proof load: 20,515 lbs · Clamp load (75%): 15,386 lbs

Surface Condition	K Factor	ft·lbs	N·m	in·lbs	kgf·cm
Plain/Dry	0.2	192.3	260.7	2307.6	2658.4
Oiled	0.15	144.2	195.5	1730.4	1993.6
Zinc Plated	0.18	173.1	234.7	2077.2	2393.3
Waxed	0.1	96.2	130.4	1154.4	1329.7
MoS₂	0.12	115.4	156.5	1384.8	1595.9
Galvanized	0.25	240.4	325.9	2884.8	3323.3

Formula: T = K × D × F

Step 1 — Clamp load: F = 0.75 × 55,000 psi × 0.334 in² = 13,778 lbs

Step 2 — Torque (dry): T = 0.20 × 0.75 in × 13,778 lbs ÷ 12 = 172.2 ft·lbs

Proof stress per SAE J429 Table 3. Stress area per ASME B1.1. K-factor per VDI 2230.

General-purpose, non-critical bolting. Most common ungraded hardware-store bolts.

• Torque values are for standard hex bolts with unified threads per ASME B1.1. Socket head cap screws may have different requirements.
• Lubrication reduces required torque significantly — using dry torque values on lubricated bolts risks exceeding yield strength.
• For critical or safety-related applications, always consult the manufacturer's specifications or applicable design standard.
• Re-used bolts may have altered friction characteristics. Inspect threads before reuse.

Size3/4"

Grade2

Diameter0.75" (19.05 mm)

TPI (UNC)10

Tensile74,000 psi

Yield57,000 psi

Proof55,000 psi