High Tensile Bolt 10.9 / 12.9
High-tensile bolts are the primary structural fastener in steel construction, bridges and heavy machinery. Mechanical properties are verified to ISO 898-1 with hardness, tensile, proof load and impact test reports issued per batch.
- Structural steel connections and steelwork
- Wind turbine and transmission tower bolting
- Heavy machinery, presses and cranes
Email rfq@yitorch.com · WhatsApp +86 176 1138 2036
Specification
| Standard | DIN 931 / 933 / 6914, ISO 898-1, ASTM A325 / A490 equivalent |
|---|---|
| Size range | M6 – M48 |
| Grade / property class | 10.9 / 12.9 (also 8.8 S and 10.9 S structural) |
| Material | Alloy steel 35CrMo, 40Cr, SCM435, B7 |
| Surface finish | Black oxide, zinc plated, Dacromet, geomet, HDG |
| MOQ | Flexible — trial orders accepted; exact MOQ confirmed with the quotation |
| Lead time | 7–20 working days for stock sizes; 25–35 days for OEM tooling |
| Packaging | Cartons on pallets, neutral or your own branded packing |
| Quality documents | Mill test certificate, dimensional report, coating thickness report on request |
| Inspection | 4-stage in-house QC; SGS / BV / TUV third-party inspection welcome |
How to order
- Send size, material or grade, finish, standard and target quantity.
- We confirm the specification and return a quotation with lead time within 48 hours.
- Approve a sample or pre-production batch if required.
- Production with 4-stage QC; inspection report and mill certificate issued before dispatch.
Quality documents supplied
- Mill test certificate (chemical composition and mechanical properties)
- Dimensional inspection report against the ordered standard
- Coating thickness and salt-spray report where applicable
- Batch traceability record and packing list
High Tensile Bolt 10.9 / 12.9 — questions buyers ask
Can you produce High Tensile Bolt 10.9 / 12.9 to my own drawing?
Yes. Send a drawing or sample and we will confirm dimensions, material, grade and finish, then quote tooling and unit price within 48 hours. We work to DIN, ISO, ASTM, GB, GOST and customer drawings.
What is the lead time and MOQ for High Tensile Bolt 10.9 / 12.9?
Standard sizes typically ship in 7–20 working days; custom or tooled items take 25–35 days. MOQ is flexible and trial quantities are accepted so you can verify quality before scaling.
What is your MOQ? Can I start with a trial order?
Yes. We support flexible MOQ and small trial orders so you can test quality and market demand before scaling up. Exact MOQ depends on the item and specification.
How fast will I get a quote?
Within 48 hours after receiving your specification (size, material, standard, finish, quantity). Urgent inquiries are usually answered the same working day.
Can you make custom sizes or OEM per my drawings?
Yes. We handle OEM and ODM: custom dimensions, materials, surface treatment and packaging per your drawings or samples, produced to DIN, ISO, ASTM, GB or GOST standards.
Technical data for High Tensile Bolt 10.9 / 12.9
| Property class | Nominal tensile Rm, min | Lower yield ReL, min | Elongation A, min | Typical core hardness |
|---|---|---|---|---|
| 8.8 | 800 MPa | 640 MPa | 12 % | ≈ 250–320 HV |
| 10.9 | 1,040 MPa | 940 MPa | 9 % | ≈ 320–380 HV |
| 12.9 | 1,220 MPa | 1,100 MPa | 8 % | ≈ 385–435 HV |
Minimum requirements of ISO 898-1 / ISO 3506-1 for the property classes above. Acceptance is against the EN 10204 3.1 mill test certificate of the actual production heat — request it with the quotation if your QC department needs the format in advance.
Thread and tolerance
- External thread 6g, internal 6H (6f / 6G on request)
- Coarse pitch standard; fine pitch available per size
- Product grade A for d ≤ 24 mm, B above, unless your drawing states otherwise
- Head marking: property class plus manufacturer mark (required from M5)
Coating options and where they belong
- Zinc plated (Cr3) — 5–12 µm, indoor and general machinery
- Hot-dip galvanized (ISO 1461) — local min ≈ 45 µm, outdoor and structural
- Zinc flake (ISO 10683) — 4–10 µm, high-strength classes and tight tolerances
- Stainless passivated (ASTM A967) — A2 / A4 where coatings are unsuitable
Hydrogen embrittlement
Electroplated fasteners of property class 10.9 and above — and 12.9 in all cases — require a documented de-embrittlement bake. We supply the process record (plating date, bake start, temperature, duration) with any such order, and we will advise against hot-dip galvanizing for 12.9 rather than accept the risk silently.
Documents that ship with this product
- EN 10204 3.1 mill test certificate per heat
- Dimensional inspection report with go / no-go thread gauge results
- Coating thickness report; neutral salt spray report on request
- De-embrittlement record where class 10.9 / 12.9 is electroplated
- Pre-shipment inspection report; third-party inspection (SGS / BV / TÜV / Intertek) on request
Full list and how to specify it in your PO: inspection documents. Standard equivalences for this item: cross-reference table. Property class background: technical data. Export compliance: compliance centre.
Ready to source quality hardware from China?
Send your specification or drawing for high tensile bolt 10.9 / 12.9 — quotation, MOQ and lead time within 48 hours.