3/4" Grade 5 Torque Specification

Torque Values by Surface Condition

Stress area: 0.334 in² · Proof load: 28,390 lbs · Clamp load (75%): 21,292 lbs

Surface Condition	K Factor	ft·lbs	N·m	in·lbs	kgf·cm
Plain/Dry	0.2	266.2	360.9	3194.4	3680.2
Oiled	0.15	199.6	270.6	2395.2	2759.4
Zinc Plated	0.18	239.5	324.7	2874.0	3311.0
Waxed	0.1	133.1	180.5	1597.2	1840.6
MoS₂	0.12	159.7	216.5	1916.4	2207.7
Galvanized	0.25	332.7	451.1	3992.4	4600.0

Stress area: 0.373 in² · Proof load: 31,705 lbs · Clamp load (75%): 23,779 lbs

Surface Condition	K Factor	ft·lbs	N·m	in·lbs	kgf·cm
Plain/Dry	0.2	297.2	402.9	3566.4	4108.5
Oiled	0.15	222.9	302.2	2674.8	3081.6
Zinc Plated	0.18	267.5	362.7	3210.0	3698.5
Waxed	0.1	148.6	201.5	1783.2	2054.7
MoS₂	0.12	178.3	241.7	2139.6	2464.7
Galvanized	0.25	371.5	503.7	4458.0	5136.3

Formula: T = K × D × F

Step 1 — Clamp load: F = 0.75 × 85,000 psi × 0.334 in² = 21,292 lbs

Step 2 — Torque (dry): T = 0.20 × 0.75 in × 21,292 lbs ÷ 12 = 266.2 ft·lbs

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

Automotive, agricultural equipment, general machinery — the most common high-strength SAE grade. Equivalent to ISO 8.8.

• 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"

Grade5

Diameter0.75" (19.05 mm)

TPI (UNC)10

Tensile120,000 psi

Yield92,000 psi

Proof85,000 psi