M14 Grade 4.6 Torque Specification

Torque Values by Surface Condition

Stress area: 115.44 mm² · Proof load: 25,974 N · Clamp load (75%): 19,480 N

Surface Condition	K Factor	N·m	ft·lbs	in·lbs	kgf·cm
Plain/Dry	0.2	54.5	40.2	482.4	555.7
Oiled	0.15	40.9	30.2	362.0	417.1
Zinc Plated	0.18	49.1	36.2	434.6	500.7
Waxed	0.1	27.3	20.1	241.6	278.4
MoS₂	0.12	32.7	24.1	289.4	333.4
Galvanized	0.25	68.2	50.3	603.6	695.4

Stress area: 124.55 mm² · Proof load: 28,024 N · Clamp load (75%): 21,018 N

Surface Condition	K Factor	N·m	ft·lbs	in·lbs	kgf·cm
Plain/Dry	0.2	58.8	43.4	520.4	599.6
Oiled	0.15	44.1	32.5	390.3	449.7
Zinc Plated	0.18	53.0	39.1	469.1	540.5
Waxed	0.1	29.4	21.7	260.2	299.8
MoS₂	0.12	35.3	26.0	312.4	360.0
Galvanized	0.25	73.6	54.3	651.4	750.5

Formula: T = K × D × F

Step 1 — Clamp load: F = 0.75 × 225 MPa × 115.44 mm² = 19,480 N

Step 2 — Torque (dry): T = 0.20 × 0.0140 m × 19,480 N = 54.5 N·m

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

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.

SizeM14

Class4.6

Diameter14 mm

Pitch (coarse)2.0 mm

Tensile400 MPa

Yield240 MPa

Proof225 MPa