1-1/2" Grade 5 Torque Specification

Torque Values by Surface Condition

Stress area: 1.405 in² · Proof load: 103,970 lbs · Clamp load (75%): 77,978 lbs

Surface Condition	K Factor	ft·lbs	N·m	in·lbs	kgf·cm
Plain/Dry	0.2	1949.4	2643.0	23392.8	26951.2
Oiled	0.15	1462.1	1982.3	17545.2	20213.9
Zinc Plated	0.18	1754.5	2378.8	21054.0	24257.1
Waxed	0.1	974.7	1321.5	11696.4	13475.6
MoS₂	0.12	1169.7	1585.9	14036.4	16171.7
Galvanized	0.25	2436.8	3303.9	29241.6	33690.5

Stress area: 1.581 in² · Proof load: 116,994 lbs · Clamp load (75%): 87,746 lbs

Surface Condition	K Factor	ft·lbs	N·m	in·lbs	kgf·cm
Plain/Dry	0.2	2193.6	2974.1	26323.2	30327.5
Oiled	0.15	1645.2	2230.6	19742.4	22745.9
Zinc Plated	0.18	1974.3	2676.8	23691.6	27295.9
Waxed	0.1	1096.8	1487.1	13161.6	15164.3
MoS₂	0.12	1316.2	1784.5	15794.4	18196.9
Galvanized	0.25	2742.0	3717.7	32904.0	37910.1

Formula: T = K × D × F

Step 1 — Clamp load: F = 0.75 × 74,000 psi × 1.405 in² = 77,978 lbs

Step 2 — Torque (dry): T = 0.20 × 1.5 in × 77,978 lbs ÷ 12 = 1949.4 ft·lbs

Proof stress per SAE J429 Table 3. Stress area per ASME B1.1. K-factor per VDI 2230.

Same as Grade 5 but with reduced strength at larger diameters

• Torque values are for standard hex bolts with unified threads per ASME B1.1. 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.
• Re-used bolts may have altered friction characteristics. Inspect threads before reuse.

Size1-1/2"

Grade5

Diameter1.5" (38.10 mm)

TPI (UNC)6

Tensile105,000 psi

Yield81,000 psi

Proof74,000 psi