What is ISO 3506-1- Mechanical properties of corrosion-resistant stainless steel fasteners about?
ISO 3506-1 is the first in a six-part series of international standards on the mechanical and physical properties of stainless steel fasteners.
ISO 3506-1 specifies the mechanical and physical properties of bolts, screws and studs, with coarse pitch thread and fine pitch thread, made of corrosion-resistant stainless steels and also specifies property classes about austenitic, martensitic, ferritic and duplex steel grades for fasteners.
ISO 3506-1 applies to bolts, screws and studs with:
- ISO metric thread in accordance with ISO 68-1
- Diameter/pitch combinations in accordance with ISO 261 and ISO 262
- Coarse pitch thread M1,6 to M39, and fine pitch thread M8×1 to M39×3
- Thread tolerances in accordance with ISO 965-1 and ISO 965-2
- Specified property classes and of any shape
Who is ISO 3506-1- Mechanical properties of corrosion-resistant stainless steel fasteners for?
ISO 3506-1 on mechanical and physical properties of fasteners is relevant to:
- Manufacturers and distributors of stainless steel fasteners
- Structural and consulting engineers
- Construction and civil engineering contractors and larger sub-contractors
- Test houses and laboratories
- Industries associated with oil and gas production and distribution
Why should you use ISO 3506-1 - Mechanical properties of corrosion-resistant stainless steel fasteners?
ISO 3506-1 specifies the mechanical and physical properties of bolts, screws and studs, with coarse pitch thread and fine pitch thread, made of corrosion-resistant stainless steels, when tested at the ambient temperature range of 10 °C to 35 °C.
ISO 3506-1 specifies property classes in relation to austenitic, martensitic, ferritic and duplex (austenitic-ferritic) steel grades for fasteners.
Together with ISO 3506-2:2020 and ISO 3506-6:2020, it provides additional advice and guidance for most applications where these products will be required. This considerably revised document provides an excellent foundation for any assessment.
What’s changed since the last update?
BS EN ISO 3506-1:2020 supersedes EN ISO 3506-1:2009. The main changes are:
- Duplex (austenitic-ferritic) stainless steels for property classes 70, 80 and 100 have been added
- Property class 100 for austenitic stainless steel grades as well as grade A8 have been added
- Finish has been added
- The matching of stainless steel bolt and nut grades has been added
- Calculated minimum ultimate tensile loads and minimum loads at 0,2 % non-proportional elongation and rounding rules have been added
- Reduced loadability for fasteners due to head or shank design has been added
- Requirements and guidance for inspection procedures have been added
- Operational temperature ranges have been clarified
- The applicability of test methods, also in relation to full or reduced loadability, has been added
- The tensile test procedure has been entirely amended, and application to fasteners with reduced loadability has been added
- The wedge tensile test and hardness test have been improved
- Marking and labelling have been improved, and fasteners with reduced loadability have been included
- Mechanical properties at elevated temperatures and application at low temperatures have been improved

