M36 Grade 4.6 Torque Specification

Torque Values by Surface Condition

Stress area: 816.72 mm² · Proof load: 183,762 N · Clamp load (75%): 137,822 N

Surface Condition	K Factor	N·m	ft·lbs	in·lbs	kgf·cm
Plain/Dry	0.2	992.3	731.9	8782.6	10118.7
Oiled	0.15	744.2	548.9	6586.7	7588.8
Zinc Plated	0.18	893.1	658.7	7904.6	9107.1
Waxed	0.1	496.2	366.0	4391.7	5059.9
MoS₂	0.12	595.4	439.1	5269.7	6071.4
Galvanized	0.25	1240.4	914.9	10978.5	12648.6

Stress area: 864.95 mm² · Proof load: 194,614 N · Clamp load (75%): 145,960 N

Surface Condition	K Factor	N·m	ft·lbs	in·lbs	kgf·cm
Plain/Dry	0.2	1050.9	775.1	9301.3	10716.2
Oiled	0.15	788.2	581.3	6976.2	8037.4
Zinc Plated	0.18	945.8	697.6	8371.0	9644.5
Waxed	0.1	525.5	387.6	4651.1	5358.6
MoS₂	0.12	630.5	465.0	5580.4	6429.3
Galvanized	0.25	1313.6	968.9	11626.3	13395.0

Formula: T = K × D × F

Step 1 — Clamp load: F = 0.75 × 225 MPa × 816.72 mm² = 137,822 N

Step 2 — Torque (dry): T = 0.20 × 0.0360 m × 137,822 N = 992.3 N·m

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

Non-critical assemblies, light-duty applications, general-purpose hardware where high strength is not required

• 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

Class4.6

Diameter36 mm

Pitch (coarse)4.0 mm

Tensile400 MPa

Yield240 MPa

Proof225 MPa