M36 Grade 5.6 Torque Specification

Torque Values by Surface Condition

Stress area: 816.72 mm² · Proof load: 228,682 N · Clamp load (75%): 171,511 N

Surface Condition	K Factor	N·m	ft·lbs	in·lbs	kgf·cm
Plain/Dry	0.2	1234.9	910.8	10929.8	12592.5
Oiled	0.15	926.2	683.1	8197.6	9444.6
Zinc Plated	0.18	1111.4	819.7	9836.7	11333.2
Waxed	0.1	617.4	455.4	5464.5	6295.8
MoS₂	0.12	740.9	546.5	6557.5	7555.1
Galvanized	0.25	1543.6	1138.5	13662.0	15740.4

Stress area: 864.95 mm² · Proof load: 242,186 N · Clamp load (75%): 181,640 N

Surface Condition	K Factor	N·m	ft·lbs	in·lbs	kgf·cm
Plain/Dry	0.2	1307.8	964.6	11575.0	13335.9
Oiled	0.15	980.9	723.5	8681.7	10002.4
Zinc Plated	0.18	1177.0	868.1	10417.3	12002.1
Waxed	0.1	653.9	482.3	5787.5	6667.9
MoS₂	0.12	784.7	578.8	6945.2	8001.7
Galvanized	0.25	1634.8	1205.8	14469.2	16670.4

Formula: T = K × D × F

Step 1 — Clamp load: F = 0.75 × 280 MPa × 816.72 mm² = 171,511 N

Step 2 — Torque (dry): T = 0.20 × 0.0360 m × 171,511 N = 1234.9 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.

SizeM36

Class5.6

Diameter36 mm

Pitch (coarse)4.0 mm

Tensile500 MPa

Yield300 MPa

Proof280 MPa