Calculate tightening torque, preload and surface pressure for hex head and socket head screws.

Based on VDI 2230:2014

Bossard calculators and converters are designed for engineers, technicians, designers and students involved in the development and assembly of bolted joints. 


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Screw Type

Clearance Hole ISO 273

Data used in calculation
Login required N/mm²
Login required mm
Login required mm
Login required mm
Login required mm
Login required mm
Login required mm²
Maximum allowable tightening torque: Login Nm
Maximum possible preload: Login kN
Maximum surface pressure under screw head/nut: Login N/mm²

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