DIN 940 Studs, Metal End ≈2,5d
DIN 940 double-ended studs with ≈2,5d metal end, M4 to M24 including fine-pitch variants: engagement b1, nut-end b2 by length band, shank ds and the length ladder to 200 mm.
Last updated: 2026-11
Specifications
DIN 940 is the stud for screwed joints where the metal (wrench-flat-free) end screws permanently into the housing — its ≈2,5d engagement length b1 (10 at M4, 17 at M12, 30 at M24) is sized for steel housings, while the nut end b2 is printed in the same three grip bands used on hex bolts (l≤125, l>125≤200, l>200; at M12: 30/36/49). The 07/2010-edition table carries coarse and fine-pitch variants in shared columns (the headers print "M 8 M8X1", "M 10 M10X1.25", "M 12 M12X1.5" through "M 24 M24X2"), the transition shank ds min/max between the two threads, and the x1 thread-runout value. Lengths run 12 to 200 mm with the mass table per size and length. Studs order when the housing thread cannot survive repeated assembly — the stud goes in once, the nut does the servicing.
| Standard / scope | DIN 940 studs, metal end ≈2,5d — M4 to M24, coarse and fine pitch (edition 07/2010, supersedes 02/1995) |
|---|---|
| Engagement b1 nom | ≈2,5d metal end: 10 (M4), 12.5-class (M5), 15 (M6), 17 (M8-class), 20 (M10-class), 24 (M12-class), 30 (M24) |
| Nut end b2 | By grip band l≤125 / >125≤200 / >200: M8 22/28/41, M12 30/36/49, M24 54/60/73 |
| Transition shank ds | min/max per size — the plain portion between the two threads (also the turning diameter for housing fit) |
| Commercial lengths l | Ladder 12 to 200 mm; approximate mass per 1000 pcs (ρ=7,85 kg/dm³) tabulated per size/length |
| Not tabulated | Property class, finish, tapped-hole depth recommendation — state at quotation |
Materials
- Studs order in property classes matched to the housing: 5.8/8.8 for general steel work, 10.9/12.9 for high-loaded flanges, A2/A4 stainless for corrosive service — and the fine-pitch columns exist because the nut end often wants the finer thread even when the engagement end stays coarse. State which end is which on the RFQ (metal end into the housing, b1 per the standard), the housing material (the ≈2,5d engagement assumes steel; aluminium wants a longer engagement or a different standard), and finish
Ordering & documentation
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 (DIN 940 Studs, Metal End ≈2,5d) 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.
Frequently asked questions
DIN 939 also covers studs — how do I choose between the two metal ends?
By engagement length: DIN 939 carries the ≈1,25d metal end for through or deep steel housings, while the DIN 940 tabulated here carries ≈2,5d for the shorter, blind or softer housings where every millimetre of thread counts — the b1 column is the discriminator (17 mm at M12-class versus roughly half that on 939). Read your tapped-hole depth: the metal end must bottom out with a thread or two to spare, so a shallow boss wants the long 940 end, and a deep through-hole is usually cheaper on 939. If the drawing names the standard, follow it — the two are not interchangeable in a blind hole without re-checking depth.
The column headers print both coarse and fine pitch (e.g. "M 12 M12X1.5") — which pitch am I getting?
The column serves the pair: the b1/b2/ds values are common to both, and the pitch you receive is what the order states — coarse by default, fine where the header names it (M8X1, M10X1.25, M12X1.5 through M24X2). The fine-pitch nut end is the common choice on vibration-exposed and hydraulic flanges. To remove ambiguity on the RFQ, write the full designation — "stud DIN 940 M12×1.5 nut end × 80, metal end M12 coarse" — and we confirm both threads and the ds transition on the order acknowledgement before production.
Related knowledge
- What Bolt Property Classes 8.8, 10.9 and 12.9 Encode — and When High Strength Stops Being the Right Choice
- Bolt Grade Selection: ISO 898-1 8.8/10.9/12.9 vs ASTM A307 and A325
- 8.8 vs 10.9 vs 12.9 Bolts: Strength, Hardness and Cost — What the Evidence Settles
- Calculating Bolt Preload and Clamp Force: Torque, Friction and Tightening Method
- How to Determine Tightening Torque and Choose a Tightening Method for a Bolted Joint
- Fastener Failure Modes: Which Fatigue, Creep and SCC Controls the Evidence Supports
- Hydrogen Embrittlement in High-Strength Bolts: Which Grades Need Controls, Which Coatings and Baking Schedules Are Acceptable, and What to Require Before the RFQ
Request a Quote
Get factory-direct pricing from the manufacturer.
What to include in your inquiry
- ✓ Standard and property class (e.g. DIN 912, ISO 4762, class 8.8) — or a drawing for custom parts.
- ✓ Sizes, lengths and thread type (metric or inch).
- ✓ Quantity per size and your target delivery date.
- ✓ Destination country, plus any coating or finish requirement.
- ✓ Any documents you need with the shipment (e.g. mill test certificate) so the quote includes them.
- ✓ Your inquiry goes straight to the factory team by email and gets a reply within 24 hours.
- ✓ Factory-direct pricing
- ✓ Standard and custom specifications
- ✓ Factory-direct export to buyers in Europe, Asia, the Americas and the Middle East
- ✓ Full fastener family support