Dowel Pin Carbon Steel — Factory Direct Supplier | Huaxia-Steel
Dowel pins are precision cylindrical fasteners used for alignment, positioning, and load transfer in mechanical assemblies, tooling fixtures, and structural connections. At Huaxia-Steel, we manufacture carbon steel dowel pins to international standards with tight dimensional tolerances, delivering consistent quality for OEMs, machinery builders, and construction projects worldwide.
Product Overview
Carbon steel dowel pins from Huaxia-Steel are produced from quality medium-carbon steel (typically 1045/C45 or equivalent) and are available in hardened and unhardened conditions. Our pins are manufactured by cold drawing, centerless grinding, and precision cutting to achieve consistent diameters, straightness, and surface finish. Standard surface treatments include plain (oiled), zinc-plated, and black oxide finishes, with custom coatings available by request.
Dowel pins serve as precision locators in machine assemblies — they ensure perfect alignment between mating components, resist shear forces, and maintain positional accuracy under vibration and thermal cycling. Unlike bolts, dowel pins are not threaded and rely on interference fit for retention.
Specifications & Dimensions
| Parameter | Standard Range | Custom Capability |
|---|---|---|
| Diameter | 2mm – 50mm | Up to 100mm |
| Length | 5mm – 300mm | Up to 500mm |
| Diameter Tolerance | m6, h7, h8, p6 | Custom tolerance on request |
| Surface Finish (Ra) | 0.4 – 0.8 μm | 0.2 μm for precision applications |
| Chamfer | Standard 15°–30° both ends | Single-end or custom angle |
| Hardness (hardened) | 58–62 HRC (surface) | Case depth 0.5–2.0mm |
| Hardness (unhardened) | 170–210 HB | — |
| Straightness | 0.05mm per 100mm | 0.02mm per 100mm |
Standard sizes in stock (diameter × length):
- 3mm × 12mm, 3mm × 20mm, 3mm × 30mm
- 4mm × 16mm, 4mm × 25mm, 4mm × 40mm
- 5mm × 20mm, 5mm × 30mm, 5mm × 50mm
- 6mm × 20mm, 6mm × 30mm, 6mm × 40mm, 6mm × 60mm
- 8mm × 25mm, 8mm × 35mm, 8mm × 50mm, 8mm × 80mm
- 10mm × 30mm, 10mm × 50mm, 10mm × 80mm, 10mm × 100mm
- 12mm × 40mm, 12mm × 60mm, 12mm × 100mm
- 16mm × 50mm, 16mm × 80mm, 16mm × 120mm
- 20mm × 60mm, 20mm × 100mm
- Larger diameters and custom lengths available by production order
Available Steel Grades
| Grade | Standard | Carbon % | Condition | Typical Use |
|---|---|---|---|---|
| 1045 / C45 | ASTM / EN | 0.43–0.50 | Unhardened or surface-hardened | General mechanical, alignment pins |
| 1018 / C15 | ASTM / EN | 0.15–0.20 | Case-hardened | Wear-resistant pins with tough core |
| S45C | JIS G4051 | 0.42–0.48 | Induction-hardened | High-load machine tool alignment |
| AISI 4140 | ASTM A29 | 0.38–0.43 | Through-hardened | High-strength applications with Cr-Mo alloy |
| Stainless 304 | ASTM A276 | — | As-drawn | Corrosion-resistant applications |
Manufacturing Standards
Our carbon steel dowel pins are manufactured to the following international standards:
- ISO 8734: Parallel pins (dowel pins) of hardened steel and martensitic stainless steel — the primary international standard
- DIN 6325: Parallel pins, hardened — German standard (equivalent to ISO 8734)
- ISO 2338: Parallel pins, unhardened — for non-hardened applications
- DIN 7: Parallel pins, unhardened — German standard (equivalent to ISO 2338)
- ANSI/ASME B18.8.2: Taper Pins, Dowel Pins, Straight Pins, Grooved Pins, and Spring Pins — American standard
- JIS B 1354: Parallel pins — Japanese standard
Each production batch is accompanied by dimensional inspection reports and, where specified, material test certificates to EN 10204 Type 3.1 or ASTM MTR format.
Applications
Carbon steel dowel pins are used across a wide range of industries:
Quality Assurance
Every batch of Huaxia-Steel dowel pins undergoes the following quality checks:
- Dimensional inspection: Diameter measured at 3 positions along length using calibrated micrometers (0.001mm resolution). Length, chamfer angle, and straightness verified.
- Surface finish: Ra measurement using profilometer per ISO 4287. Visual inspection for surface defects including scratches, pits, and scale.
- Hardness testing: Rockwell C (HRC) for hardened pins, Brinell (HB) for unhardened. Case depth measurement on hardened pins using micro-hardness traverse.
- Material verification: Optical emission spectroscopy (OES) for chemical composition verification. Tensile testing for mechanical properties on sample lots.
- Plating inspection: Coating thickness measurement (magnetic or XRF method) for plated pins. Salt spray testing per ISO 9227 / ASTM B117 available on request.
All inspection records are maintained in our ISO 9001:2015 certified quality management system and are available with each shipment.
Packaging & Shipping
Dowel pins are packaged in the following configurations:
Typical delivery times: 7–15 days for standard stock sizes; 20–35 days for custom sizes and hardened pins. FOB/CIF/CFR terms available to major ports worldwide. Air freight available for urgent orders (3–7 days delivery).
Get a Quotation for Carbon Steel Dowel Pins
Contact Huaxia-Steel with your dowel pin requirements — specify diameter, length, tolerance class (m6/h7/h8), material grade, hardness condition, surface treatment, and quantity. Our team will provide a competitive quotation within 24 hours, including full technical compliance confirmation against your specified standard.
