Kedjehjul för skördetröskor
The modern combine harvester is one of the most chain-drive-intensive machines in existence — a 400 hp broadacre machine may carry 30 to 60 individual roller chain drives, each responsible for a specific harvesting function from the header reel to the clean grain elevator. Combine harvester sprockets operate in some of the most hostile environments in Australian agriculture: abrasive grain dust, straw chaff, heat, shock loads from uneven crop ingestion, and continuous operation for 12–18 hours per day during harvest. View our agricultural sprocket range →
Översikt
Combine harvester chain drives are categorised by their function and load level:
- ✓Header drives: ANSI #50 / #60 drives powering the cutter bar, reel, and auger in the front header. Subject to shock loads from ground contact and crop ingestion surges.
- ✓Feeder house elevator chain: Heavy-duty ANSI #80 or #100 sprocket-driven slat chain that conveys the cut crop from the header into the threshing system.
- ✓Threshing and separation drives: ANSI #60 / #80 chains driving the threshing drum, concave adjustment, and straw walker systems.
- ✓Grain elevator chains: Clean grain and tailings elevators use ANSI #50 / #60 sprockets and stud-link chains to carry grain from the sieves to the grain tank.
- ✓Grain tank unloading auger drive: ANSI #80 chains and sprockets drive the unloading auger system for tank emptying on-the-go.
Tekniska specifikationer
| Parameter | Combine Value | Räckvidd |
|---|---|---|
| Chain Standard (header) | ANSI #50 / #60 | ANSI #40–#100 |
| Chain Standard (feeder house) | ANSI #80 / #100 | ANSI #80–#120 |
| Pitch (header) | 15.875 mm / 19.05 mm | — |
| Pitch (feeder house) | 25.4 mm / 31.75 mm | — |
| Tooth Count (drive) | 13T – 21T | 9T – 38T |
| Material | C45 / 40Cr alloy (feeder house) | — |
| Tandhårdhet | HRC 50–60 | HRC 48–62 (alloy) |
| Falldjup | 1,5–3,0 mm | Up to 4 mm (feeder house) |
| Shock Load Rating | High (crop surge) | — |
| Navstil | Type B finished bore | Taper-bushed for seasonal service |
| Borrningstolerans | H7 | H6 for precision drives |
| Yta | Black oxide / zinc | — |
| Strand | Simplex / Duplex | Triplex for feeder house on large combines |
| Driftsmiljö | Grain dust, chaff, moisture | Sealed-hub on request |
| Driftstemperatur | −5°C to +80°C | — |
| Smörjning | Manual (header/external) | Oil bath (internal gearbox) |
| Bearbetningsklass | DIN-klass 6 | — |
| Deformation efter HT | ≤0,05 mm | — |
| Dokumentation | Batchcertifikat på begäran | — |
Performance Advantages vs. Generic Sprockets
| 🔥 | Induction-Hardened to HRC 50–60 | Generic import sprockets are often supplied at HRC 30–40 or with inconsistent hardness across the tooth profile. Our induction-hardened teeth deliver 2–3× longer service life in the abrasive grain-dust environment of a combine harvester. |
| 🥋 | Tough Core for Shock Loads | Crop surge and stone ingestion create instantaneous torque spikes of up to 10× rated load. Our tough C45 core (HRC 28–35) absorbs these shock loads without tooth fracture — a known failure mode of fully hardened or poorly heat-treated sprockets. |
| 📋 | Finished Bore for Seasonal Fit | Delivered pre-machined to your shaft diameter specification — no on-farm boring required. The H7 bore tolerance ensures zero fretting on the combine drive shaft across the full harvest season. |
| 🚚 | Complete Range for All Drive Positions | From the small ANSI #40 reel-speed adjuster sprocket to the large ANSI #100 feeder-house elevator sprocket, we manufacture the complete combine drive train sprocket set — supply all positions from one supplier. |
Kompatibilitetsinformation
| Drive Position / Chain | Rekommenderat kedjehjul | Anteckningar |
|---|---|---|
| Header cutter bar chain (ANSI #50) | ANSI #50 sprocket Z=13–19 | Replace as matched set with chain |
| Header reel drive (ANSI #40) | ANSI #40 kedjehjul | Variable-speed reel adjuster |
| Feeder house slat chain (ANSI #80 / #100) | ANSI #80 or #100 heavy-duty sprocket | 40Cr alloy for large machines |
| Grain elevator (ANSI #50 / #60) | ANSI #50 or #60 sprocket | Clean grain elevator and tailings return |
| Threshing drive chain (ANSI #60) | ANSI #60 sprocket | High-torque, moderate-speed |
| Unloading auger drive (ANSI #80) | ANSI #80 sprocket | High intermittent torque |
| John Deere, Case IH, New Holland combines (ref only) | ANSI #40–#100 interchangeable | Verify tooth count and bore before ordering |
| CLAAS, Fendt, Massey Ferguson (ref only) | ISO 10B–20B or ANSI equivalent | Measure chain pitch carefully |
Selection Guide for Combine Sprockets
1
📑 Consult the combine service manualThe service manual lists every chain drive position with chain part number, pitch, tooth count, and sprocket bore specification. Use this as your primary reference for replacement sprocket selection.
2
🔬 Measure chain pitch on worn examplesIf the manual is unavailable, measure the chain pitch (pin-to-pin over 10 links ÷ 10). Verify ANSI or ISO standard from roller diameter. Count teeth on the worn sprocket.
3
🔧 Specify bore and keywayFor finished bore sprockets, specify shaft diameter (measure with vernier callipers) and keyway dimensions (width and depth). H7 tolerance is standard for combine drive shafts.
4
🚚 Order pre-harvestPlan sprocket replacement during the pre-harvest service window (typically 6–8 weeks before harvest start). Australian grain harvests are time-critical — a failed sprocket during harvest peak can cost $5,000–$20,000 per day in downtime.
Installation for Combine Harvester Sprockets
- Pre-harvest service window: Replace all sprockets showing tooth wear >15% during the annual pre-harvest service. Do not wait for in-field failure.
- Isolate all drives: Engine off, all drives disengaged, PTO and feeder house declutched. For header chain drives, lower header to the ground and block safely.
- Remove guards and access covers as required. Photograph or sketch chain routing for each position before disassembly.
- Open chain at connecting link. For ANSI #80 and above, use a hydraulic chain-break tool. Do not hammer chain pins through on hardened chain links.
- Remove worn sprocket. Inspect shaft and bore for fretting. Apply anti-seize to shaft if sprocket was difficult to remove, to ease next service.
- Install new sprocket. H7 bore should slide onto the shaft with light hand pressure. Torque set-screw or retaining bolt to specification — refer to combine service manual for torque values by position.
- Install new matching chain. Close connecting link, orient clip away from direction of travel. Set tension per service manual (typically 20–30 mm deflection at mid-span for combine header chains).
- Run-in at low RPM: Engage drives at low engine RPM for 5 minutes before going to full harvest speed. Check all new chain positions for unusual noise or vibration.
Troubleshooting Combine Harvester Sprockets
| Symptom | Probable Cause | Recommended Action |
|---|---|---|
| Header chain breaking at engagement | Worn sprocket causing chain wrap at engagement | Replace sprocket and chain; check feeder house relief |
| Grain elevator chain skipping | Worn elevator sprocket — tooth tips hooked | Replace elevator drive and tail sprockets together |
| Feeder house slugging | Worn feeder chain sprocket reducing grip | Inspect and replace feeder house sprockets |
| Rapid tooth wear (1 season) | Abrasive grain dust ingestion without lubrication | Verify lubrication; upgrade to HRC 60 sprocket |
| Unloading auger drive noise | Worn or misaligned auger drive sprocket | Inspect sprocket; check auger shaft alignment |
