M10 Grade 4.8 Torque Specification

Torque Values by Surface Condition

Stress area: 58.0 mm² · Proof load: 17,980 N · Clamp load (75%): 13,485 N

Surface Condition	K Factor	N·m	ft·lbs	in·lbs	kgf·cm
Plain/Dry	0.2	27.0	19.9	239.0	275.3
Oiled	0.15	20.2	14.9	178.8	206.0
Zinc Plated	0.18	24.3	17.9	215.1	247.8
Waxed	0.1	13.5	10.0	119.5	137.7
MoS₂	0.12	16.2	11.9	143.4	165.2
Galvanized	0.25	33.7	24.9	298.3	343.6

Stress area: 61.2 mm² · Proof load: 18,972 N · Clamp load (75%): 14,229 N

Surface Condition	K Factor	N·m	ft·lbs	in·lbs	kgf·cm
Plain/Dry	0.2	28.5	21.0	252.2	290.6
Oiled	0.15	21.3	15.7	188.5	217.2
Zinc Plated	0.18	25.6	18.9	226.6	261.0
Waxed	0.1	14.2	10.5	125.7	144.8
MoS₂	0.12	17.1	12.6	151.3	174.4
Galvanized	0.25	35.6	26.3	315.1	363.0

Formula: T = K × D × F

Step 1 — Clamp load: F = 0.75 × 310 MPa × 58.0 mm² = 13,485 N

Step 2 — Torque (dry): T = 0.20 × 0.0100 m × 13,485 N = 27.0 N·m

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

Light structural connections, furniture assembly, non-load-bearing joints

• 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.

SizeM10

Class4.8

Diameter10 mm

Pitch (coarse)1.5 mm

Tensile420 MPa

Yield340 MPa

Proof310 MPa