Does ISO 898-1 specify tightening preload or torque?

No. ISO 898-1:2013 specifies mechanical and physical fastener properties and explicitly excludes torque/clamp-force performance. This page only multiplies user-supplied stress area, reference stress and fraction.

Can the result be used as a joint preload target?

Not by itself. A joint target requires load, stiffness, separation, fatigue, embedment, temperature, thread and bearing limits, tightening scatter and verification of the assembly method.

Why was the torque output removed?

A generic nut-factor preset cannot represent the actual friction distributions, geometry, coating, lubrication and assembly process. Torque/clamp behaviour should be established from qualified procedure or testing such as ISO 16047.

Scoped Engineering Calculation

Bolt Axial Reference-Load Fraction

Calculate F = η·σref·As from three user-supplied values. This is a stress-area multiplication, not an automatic joint-preload or tightening-torque design.

User-Supplied DataNo Generic TorqueNot “Preload per ISO”

Aritmetički rezultat

Selected axial load η·σref·As

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Reference-area load σref·As

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Selected axial stress η·σref

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Input fraction

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Arithmetic model

F_referenca = σ_referencaA_s; F = ηF_referenca

Because 1 MPa = 1 N/mm², stress times stress area gives newtons. The page does not decide whether σref should be proof stress, lower yield strength, 0.2% proof strength or a lower design value; use the exact value applicable to the fastener, diameter, temperature and governing procedure.

What ISO 898-1 actually covers

ISO 898-1:2013, potvrđeno 2025. i trenutno označeno za reviziju, specificira mehanička i fizikalna svojstva čeličnih/alatnih čeličnih vijaka, šrafova i šipki pri 10–35 °C. Njegov navedeni opseg metričkih navoja je M1.6–M39, a izričito ne ne specificira performanse obrtnog momenta/sile stezanja, otpornost na zamor ili otpornost na smicanje.

Joint design and assembly

VDI 2230 Part 1:2015 obuhvaća sustavno izračunavanje spojeva, uključujući minimalnu silu stezanja, promjene prednaprezanja, prednaprezanje pri sastavljanju, obrtni moment zatezanja i provjeru čvrstoće. Ova stranica s tri ulaza ne tvrdi usklađenost s VDI. ISO 16047:2005+Amd1:2012 specificira uvjete testiranja obrtnog momenta/sile stezanja; ne zamjenjuje ga univerzalna unaprijed postavljena vrijednost K.

Source responsibility: obtain As and σref from the current licensed product/thread standard, verified manufacturer data or material certificate. For stainless, elevated/low temperature, reduced-head geometry or sizes outside scope, use the applicable source rather than ISO 898-1 values.