Mechanical Properties Chart (Property Classes)

Documents

Shipments are backed by Mill Test Certificate (MTC), Dimensional Report, Salt Spray Test Report on request, with full batch traceability from raw material to finished product. Quality management follows the owner-confirmed compliance list: ISO 9001:2015, RoHS, REACH. Exact document sets are confirmed on the order.

Quotation

• The fastener family (Mechanical Properties Chart (Property Classes)) plus the standard designation from your drawing — DIN / ISO / JIS / ASTM / ANSI, or a drawing for custom parts.
• Size (diameter and length), thread type (metric or inch), property class or grade, and coating or finish.
• Quantity per size and your target delivery date.
• Destination country, and any required documents (for example a mill test certificate) so the quote includes them.

Sample & supply

Minimum order quantity is 1,000–10,000 pieces depending on size. Stock items run 3–7 days. High-strength and custom parts run 15–25 days. Quantities or variants outside the standard range are confirmed at quotation.

Storage & shipping

Parts are packed for export and shipped factory-direct to buyers in Europe, Asia, the Americas and the Middle East. Store fasteners dry and protected until installation, and keep coated parts in their packaging until use; specific packing and preservation requirements can be stated on the order and confirmed at quotation.

Why do DIN 7984 low head and DIN 912 socket caps sit at different property classes (10.9 vs 12.9) for the same M-thread?

Because the head height is the load path. A cap screw transmits its tensile load through the head, and a low head (about half the height of a DIN 912 head) has less material to carry it — so the collected chart lists DIN 7984 at class 10.9 with 832 MPa minimum tensile, against DIN 912 at 12.9 with 1220 MPa. The practical consequence at the drawing stage: if your joint was sized around a 12.9 cap screw and you swap in a low head to clear an envelope, the strength margin drops by roughly a third and the swap is a design decision, not a catalogue substitution. The same logic explains why button heads (ISO 7380, 835 MPa) and shoulder screws carry their own class rows — the chart's per-product tables exist precisely because "socket screw" is not one strength rating. Where a joint genuinely needs the low-head geometry at higher load, that is a per-case engineering call, not a stock answer.

How do I read the nut hardness ladders against the bolt classes — and what are the 04/05 classes for?

The pairing rule is that the nut must proof-load the bolt thread without stripping, which ISO 898-2 achieves by hardness windows rather than tensile minima: each class carries a Vickers band (e.g. class 8 at 200-302 HV for M5-M16, 233-353 HV for M16-M39 as printed) and the chart marks the reference acceptance method as Vickers. Classes 04 and 05 are the thin (jam/chamfered) nut classes — lower strength on purpose, used for locking and spacing, never as the structural partner of a 10.9 bolt. The style-2 (high nut) footnotes matter on the upper classes: the a/b/c notes shift the minimum values for the taller nuts because more height changes how the thread bears. When a drawing says "nut same class as bolt", read it as the ISO 898-2 class of the same number — 10 nut for 10.9 bolt — and check the size band: the M16 boundary moves the bands, and the fine-pitch ladder is its own table with decimal-comma values as printed. Any class/size combination outside these ladders is quoted per RFQ against the current edition.