Specifications
| — | — |
| Material | Alloy steel 42CrMo4 (AISI 4140) or 35CrMo; optional ductile iron GGG50 / EN-GJS-500-7 |
| Process | Silica sol investment casting + CNC turning, boring, drilling and tapping |
| Tolerance | As-cast ISO 8062-3 DCTG 5-6; bore and bearing seats to H7, +/- 0.02 mm on concentricity |
| Surface finish | As-cast Ra 6.3 um; machined sealing and bearing seats Ra 1.6 um; black oxide or e-coat optional |
| Weight range | 0.6 kg – 3.2 kg per piece |
| Heat treatment | Quench and temper to 28-34 HRC; optional carburizing of arm pivot bores; stress relieving for ductile iron grades |
| Inspection | CMM report, runout and balance check to ISO 1940 G6.3, magnetic particle inspection, EN 10204 3.1 |
Key Features
- Cast hub body with near-net tine arm lugs, cutting machining time versus a solid billet part.
- Precision bored shaft interface in H7 with keyway, spline or taper-lock options.
- Controlled concentricity between the shaft bore and arm pivot bores keeps tine timing stable.
- Quenched and tempered alloy steel resists fatigue from continuous rotor start-stop cycles.
- Rounded fillets at every lug root reduce stress risers where arms are bolted.
- Optional sealed bearing seats and grease passages machined to drawing.
- Cast-in balance pads allow final balancing without adding external weights.
Applications
- Rotary hay rake rotor hubs and tine arm carriers
- Tedder rotor heads and swath turner hubs
- Forage harvester pickup reel hubs
- Windrower and merger drive hubs
- Aftermarket rake arm hub replacement programs
Quality & Compliance
Production runs under an IATF 16949 certified system with EN 10204 3.1 material certification for every heat lot, including tensile, impact and hardness results. First-article inspection covers full dimensional layout, bore concentricity, balance grade and magnetic particle inspection, and reports are retained for the life of the program.
FAQ
Can you machine the shaft bore to our drawing tolerances?
Yes. Bores are finished by CNC turning or honing to H7 or tighter, and we verify concentricity to the arm pivot bores on a CMM for every first article.
Do you supply ductile iron instead of alloy steel?
Yes. Ductile iron EN-GJS-500-7 is a lower-cost option for lighter rakes, but 42CrMo4 quenched and tempered is recommended for high-cycle machines.
How do you handle fatigue-critical lug roots?
We design generous fillet radii, control the casting grain structure with a chilled riser layout, and verify the roots by magnetic particle inspection on production samples.
Can the hub be supplied balanced?
Yes. Hubs are balanced to ISO 1940 G6.3 on request, using the cast-in balance pads so no loose weights are needed in the field.
What surface protection do you offer?
Standard is shot blast plus anti-rust oil. Black oxide, e-coating or powder coating can be applied for machines stored outdoors.
Can you include the tine arms and bushings?
We can machine and assemble the hub with arms, bushings and fasteners as a subassembly, or ship the hub alone for your own line.
Send your drawing, 3D model or sample for a fast quotation — Wendy She — sales@cnsandcasting.com — WhatsApp +86-13777124360.
