Description
EP-NRV090 — Shaft-Input Heavy Industrial Aluminium Worm Gear Reducer
The EP-NRV090 is the shaft-input version of the NMRV90, sharing the same 90 mm centre distance, 7,306 N·m maximum output torque, and 5.5 kW input power rating in an identical die-cast aluminium housing, but configured with a solid keyed input shaft in place of the bore-input IEC flange. This configuration makes the NRV090 the natural choice when power arrives via chain sprocket, belt pulley, hydraulic motor output, or PTO-driven countershaft — driving arrangements that cannot present an IEC flange face to the gearbox. Compared with the NRV075 at 75 mm centre distance, the NRV090 delivers 11% more output torque, enabling it to handle heavier chain-driven loads while maintaining the NRV series’s lightweight aluminium housing and corrosion-resistant finish. In Australian industry, the NRV090 is particularly valued for large engine-driven agricultural and industrial conveyor systems and high-power chain-driven mixing and processing equipment in mining and chemical plants, where the solid shaft input integrates naturally into existing chain or belt drive train layouts without requiring an IEC motor adaptor or modifying the drive geometry.
Technical Specifications — EP-NRV090
| Parameter | Value |
|---|---|
| Series | NRV (Solid Shaft Input, No Input Flange) |
| Centre Distance | 90 mm |
| Reduction Ratios | 5, 7.5, 10, 15, 20, 25, 30, 40, 50, 60, 80, 100 |
| Rated Input Power | Up to 5.5 kW |
| Output Speed Range | 14 to 280 r/min (at 1400 r/min input) |
| Max Output Torque | 7,306 N·m |
| Input Type | Solid shaft input, no IEC flange |
| Housing Material | Die-cast aluminium alloy |
| Worm Wheel Material | Phosphor bronze |
| Worm Shaft Material | 20CrMnTi alloy steel, case hardened, precision ground |
| Equivalent NMRV | NMRV90 (same internal assembly) |
| Output Bore Diameter | 35 mm standard (H7 with keyway) |
| Lubrication | ISO VG 220 gear oil (factory filled) |
| Mounting Positions | B3, B6, B7, B8, V5, V6 |
| Protection Class | IP54 |
| Ambient Temperature | -10°C to +40°C |
NRV090 Performance Table (5.5 kW / 1400 r/min)
| Ratio (i) | Output Speed (r/min) | Output Torque (N·m) | Fr max Input (N) | Service Factor (fs) |
|---|---|---|---|---|
| 7.5 | 187 | 2,785 | — | 1.9 |
| 10 | 140 | 3,065 | — | 1.5 |
| 15 | 93 | 3,882 | — | 1.2 |
| 20 | 70 | 4,273 | — | 1.1 |
| 25 | 56 | 4,603 | — | 1.1 |
| 30 | 47 | 4,891 | 8,180 | 1.2 |
| 40 | 35 | 5,383 | — | 1.5 |
| 50 | 28 | 5,799 | — | 1.4 |
| 60 | 23 | 6,163 | — | 1.2 |
| 80 | 18 | 6,783 | — | 1.1 |
| 100 | 14 | 7,306 | — | 0.9 |
✅ NRV090 Standout Features
🔗 5.5 kW Shaft-Input — Engine & Hydraulic Ready
At 5.5 kW, the NRV090 handles the power outputs of medium diesel engines, large hydraulic motors, and electric motors driving via chain or belt, covering the broadest range of non-IEC drive sources in the heavy-duty shaft-input worm gearbox category.
📈 7,306 N·m — Heavy Industrial Torque
The NRV090 delivers the same 7,306 N·m as the NMRV090, confirming full torque availability at every ratio regardless of the shaft-input configuration.
◯ Large Bearing Assembly for High Radial Load
At 5.5 kW chain-drive input, radial loads on the input shaft can be substantial. The NRV090’s larger-diameter input shaft and bearing set (versus NRV075) handle chain pulls up to 8,180 N at mid-shaft for ratio 30.
⛁ Aluminium vs Cast Iron in Mining Environments
The NRV090’s aluminium housing resists the acidic mine water mist, rock dust, and temperature cycling in underground and surface mining operations where cast-iron units would require quarterly repainting and anti-rust treatment.
🅆 Self-Locking at High Ratios
At ratios 30:1 and above, the NRV090 provides reliable static self-locking, critical for inclined mining conveyors and agricultural elevator drives where the load must not backdrive the chain when the prime mover stops.
🏭 Application Sectors
🍲 Mining & Quarry Conveyors
Heavy shaft-input worm gear reducer for underground mine conveyor take-up drives, surface quarry screen feeder chain drives, and aggregate conveyor systems powered by engines or large hydraulic motors rather than standard IEC electric motors.
💧 Water Treatment Chain Drives
Industrial NRV worm gearbox for chain-driven sludge scraper mechanisms, rotating screen drives, and belt-filter press chain drives in municipal water treatment plants where the drive arrangement uses a chain from a gearmotor rather than a direct-flanged motor.
⚙ Heavy Chemical Processing
Corrosion-resistant shaft-input worm gear reduction gearbox for chain-driven chemical reactor paddle drives, slurry pump speed reducers, and industrial filter conveyor drives requiring 5.5 kW at low output speed.
🌿 Large Agricultural Equipment
High-torque worm gearmotor alternative for large-scale grain handling facilities, forage harvester conveyor chains, and heavy crop-processing equipment driven by diesel engine PTOs or large electric motor countershafts.
🔎 Specification & Sizing
Design Example — Underground Mine Conveyor Drive
Required: 5.5 kW diesel engine at 1400 r/min (via chain) driving a conveyor at 23 r/min (i=60). Output torque from table = 6,163 N·m. For heavy shock mining load fs=2.0: demand = 6,163/2.0 = 3,082 N·m — well within rating. ✅ NRV090-60 selected.
NRV090 vs NMRV090 — Which Series to Choose
| Feature | EP-NRV090 (Shaft Input) | EP-NMRV090 (Flange Input) |
|---|---|---|
| Input Configuration | Solid keyed shaft | Bore input with IEC flange |
| Best Drive Source | Chain, belt, coupling, hydraulic motor, PTO | Direct IEC face-mount motor |
| IEC Flange | Not applicable | Multiple B5/B14 sizes |
| Output Torque | Identical | Identical |
| Housing Dimensions | Identical | Identical |
| Self-Lock at i≥30 | Yes | Yes |
| Best For | Remote or non-standard drive sources | Standard motor-integrated assemblies |
NRV090 DZ/SZ Output Shaft Dimensions
| G1 (mm) | K1 (mm) | L/DZ (mm) | L1/SZ (mm) | b2 (mm) | d h6 (mm) | Keyway |
|---|---|---|---|---|---|---|
| 140 | 154.5 | 234 | 309 | 10 | 35 | M12 |
❓ FAQs — EP-NRV090
What is the maximum input shaft radial load for the NRV090?
The Fr max for the NRV090 input shaft is 8,180 N at mid-shaft for ratio 30. This is the highest input radial load rating in the NRV030–NRV090 range, reflecting the larger shaft diameter and bearing arrangement. Calculate your actual chain or belt tension and confirm it remains below this limit.
How does the NRV090 compare to the NRV075?
The NRV090 delivers 7,306 N·m max torque (vs 6,603 N·m for NRV075) and accepts 5.5 kW input (vs 4.0 kW). It also has a higher input shaft radial load rating (8,180 vs 7,380 N), making it better suited for heavy chain drives at the 4.0–5.5 kW power level.
Can the NRV090 be driven by a diesel engine countershaft?
Yes. The NRV090 solid input shaft mounts a chain sprocket or V-belt pulley driven from a diesel engine countershaft. Ensure the chain-drive ratio and engine speed result in an NRV090 input speed not exceeding 1,800 r/min for continuous operation.
Is the NRV090 suitable for inclined conveyor drives in mining?
Yes. At ratios 30:1 and above, the NRV090’s static self-locking prevents backdriving when the engine or motor stops, eliminating the need for a separate backstop device on moderate-incline mining conveyors (consult our engineering team for inclines above 20°).
What output shaft diameter is standard for the NRV090?
The standard DZ solid shaft is 35 mm h6 with an M12 key. The hollow output bore is 35 mm H7 with a 10 mm keyway. The SZ double-ended shaft, output flange (F), and hollow output flange (FL) are available as alternatives — specify when ordering.
⭐ Customer Reviews
★★★★★
“We replaced chain-driven cast-iron reducers on our underground coal mine conveyors with NRV090 units. The aluminium housing handles the acidic mine atmosphere without corrosion and the weight saving made underground installation much safer for our maintenance team.”
Steve K. — Mining Engineer, Underground Coal Operation 🇦🇺 Australia (NSW)
★★★★★
“Our wastewater treatment plant uses NRV090 units on chain-driven sludge scraper mechanisms. Three years of continuous operation in hydrogen-sulphide atmosphere — the aluminium housing shows zero corrosion compared to the cast-iron units we replaced.”
Anita R. — Plant Manager, Municipal Water Authority 🇮🇿 New Zealand
★★★★☆
“The NRV090 drives our heavy grain elevator chain from a diesel engine countershaft at ratio 50. After two harvest seasons the self-locking at power-off is perfectly reliable and we have not experienced any backdriving incidents.”
Neil B. — Farm Manager, Grain Storage 🇦🇺 Australia (Western Australia)
⚙ Accessories & Compatible Products
⚡ IEC Motors (B5/B14)
Standard single-phase and three-phase AC motors with matching IEC flange. VFD inverter-duty versions available.
🔗 Output Shaft Kits
Single solid (DZ), double-ended (SZ), output flange (F), hollow flange (FL) — all H7/h6 tolerance with standard keyways.
🔨 Torque Arms
Steel torque reaction arms for shaft-mount configurations; foot-mounting plates for B3/B6 orientations.
🔒 Seal & Breather Kits
Replacement lip-seal kits, vented breather plugs, and magnetic drain plugs for extended service intervals.
Request a Quote for EP-NRV090
Our engineering team will confirm the input shaft key specification, allowable radial load, and output shaft configuration for your chain or belt drive application.
The EP-NRV090 aluminium worm gear reducer has a 90 mm centre distance, ratios from 5 to 100, rated input power up to 5.5 kW, and maximum output torque of 7,306 N·m. Its solid shaft input makes it the ideal heavy industrial shaft-input worm gearbox for engine-driven conveyors, hydraulic-motor-driven mixing systems, and large agricultural drives where chain or belt power transmission is the established standard.
