M7 Grade 5.6 Torque Specification

Torque Values by Surface Condition

Stress area: 28.86 mm² · Proof load: 8,081 N · Clamp load (75%): 6,061 N

Surface Condition	K Factor	N·m	ft·lbs	in·lbs	kgf·cm
Plain/Dry	0.2	8.5	6.3	75.2	86.7
Oiled	0.15	6.4	4.7	56.6	65.3
Zinc Plated	0.18	7.6	5.6	67.3	77.5
Waxed	0.1	4.2	3.1	37.2	42.8
MoS₂	0.12	5.1	3.8	45.1	52.0
Galvanized	0.25	10.6	7.8	93.8	108.1

Stress area: 31.23 mm² · Proof load: 8,744 N · Clamp load (75%): 6,558 N

Surface Condition	K Factor	N·m	ft·lbs	in·lbs	kgf·cm
Plain/Dry	0.2	9.2	6.8	81.4	93.8
Oiled	0.15	6.9	5.1	61.1	70.4
Zinc Plated	0.18	8.3	6.1	73.5	84.6
Waxed	0.1	4.6	3.4	40.7	46.9
MoS₂	0.12	5.5	4.1	48.7	56.1
Galvanized	0.25	11.5	8.5	101.8	117.3

Formula: T = K × D × F

Step 1 — Clamp load: F = 0.75 × 280 MPa × 28.86 mm² = 6,061 N

Step 2 — Torque (dry): T = 0.20 × 0.0070 m × 6,061 N = 8.5 N·m

Proof stress per ISO 898-1:2013 Table 4. Stress area per ISO 898-1 Annex A. K-factor per VDI 2230.

Moderate-duty industrial applications, machinery guards, medium-strength connections

• Torque values are for standard hex bolts with ISO metric threads. 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 (e.g., VDI 2230).
• Re-used bolts may have altered friction characteristics. Inspect threads before reuse.

SizeM7

Class5.6

Diameter7 mm

Pitch (coarse)1.0 mm

Tensile500 MPa

Yield300 MPa

Proof280 MPa