Descrizione
EP-NRV090 Aluminium Worm Gearbox — Overview

The EP-NRV090 is a heavy shaft-coupled aluminium worm gearbox — a heavy-duty shaft-input unit in the NRV series, engineered around a 090 mm worm gear centre distance. Unlike the NMRV series which features a hollow-bore IEC motor flange input, the NRV090 uses a solid 28 mm solid input shaft with a precision-ground keyway, making it purpose-built for belt-driven, chain-driven, and shaft-coupled drive systems across mining conveyor gear trains, crane drives, extruder lines, and large shaft-driven pumps. The solid shaft input eliminates the need for a motor flange adaptor, enabling shorter drive train layouts and seamless integration into multi-stage gear systems. With output torques up to 5000 Nm, reduction ratios from 7.5–100:1, and a die-cast aluminium A360 housing with IP65 shaft sealing, the EP-NRV090 delivers reliable, corrosion-resistant performance for mining and heavy industrial shaft-coupled drive systems. Six mounting positions and three output configurations give machine designers full layout flexibility across Australian and international installations.
Technical Specifications — EP-NRV090


General Specifications
| Parameter | Specification |
|---|---|
| Model Number | EP-NRV090 |
| Series | NRV — Solid input shaft, no motor flange |
| Centre Distance | 090 mm |
| Max Output Torque | 5000 Nm |
| Reduction Ratios | 7.5–100:1 |
| Input Shaft Diameter | 28 mm solid |
| Input Shaft Keyway | 8×4.0 mm |
| Input Shaft Tolerance | h6 (precision ground) |
| Max Input Shaft Radial Load (Fri max) | 1270 N |
| Output Shaft Diameter | 45 mm |
| Max Recommended Input Power | 0.75 kW |
| Housing Material | Die-cast aluminium alloy A360 |
| Worm Wheel Material | Phosphor bronze |
| Worm Shaft Material | 20CrMnTi case-hardened steel, ground |
| Surface Treatment | Baked enamel paint (RAL 5010 blue) |
| Lubricant | ISO VG 220 worm gear oil, ~1.5 L |
| IP Rating | IP65 (shaft seals standard) |
| Ambient Temperature | -10°C to +40°C standard; up to +60°C with synthetic oil |
| Max Input Speed | 1,400 rpm (recommended); 1,800 rpm (max) |
| Approx. Weight | ~16 kg |
| Mounting Positions | B3, B6, B7, B8, V5, V6 |
| Output Configurations | Solid shaft / Double shaft (DZ) / Output flange (FL) |
| Input Connection | Solid shaft with keyway — use coupling, pulley, or sprocket |
| Standards | ISO 9001, CE marking |
Performance Selection Data (1,400 rpm Input)
| Ratio (i) | Output Speed (r/min) | Output Torque (Nm) | Input Power (kW) |
|---|---|---|---|
| 10:1 | 140 | 3750 | 0.75 |
| 15:1 | 93 | 4160 | 0.75 |
| 20:1 | 70 | 4420 | 0.75 |
| 25:1 | 56 | 4865 | 0.75 |
| 30:1 | 47 | 5241 | 0.75 |
| 50:1 | 28 | 5799 | 0.75 |
| 60:1 | 23 | 6163 | 0.75 |
Core Features & Benefits

◯Solid Shaft Input — No Motor Flange Required
The EP-NRV090 solid 28 mm solid input shaft accepts standard couplings, pulleys, and chain sprockets directly. Ideal for belt/chain-driven systems and multi-stage gear trains where no IEC motor flange is needed — simplifying drive layout and reducing component count.
△Corrosion-Resistant Die-Cast Aluminium Housing
A360 die-cast aluminium provides inherent corrosion resistance for food processing washdowns, coastal Australian sites, and humid industrial environments. The baked enamel finish adds UV and chemical protection for outdoor and industrial installations.
◆Precision Ground Worm Shaft — Low Noise Operation
Ground worm shaft and precision-hobbed phosphor bronze wheel deliver smooth, low-noise torque transmission. Aluminium housing vibration damping further reduces structure-borne noise in printing, packaging, and textile machinery applications.
■Six Mounting Positions + Three Output Options
B3, B6, B7, B8, V5, V6 mounting orientations combined with solid shaft, double shaft (DZ), and output flange (FL) output options provide complete layout flexibility for complex multi-axis drive systems.
▶Static Self-Locking at Ratios ≥ 40:1
At ratios of 40:1 and above, worm geometry prevents back-drive under static load — simplifying gate actuators, conveyor braking systems, and positioning drives without an external holding brake.
●Superior Heat Dissipation — Extended Oil and Seal Life
Aluminium thermal conductivity (~160 W/m·K) dissipates gear-generated heat up to 3× faster than cast iron, keeping operating temperatures lower and extending lubricant life — critical for high-duty-cycle shaft-coupled drive applications.
EP-NRV090 vs EP-NMRV090 — Which Input Type is Right for You?
The NRV and NMRV series share identical worm sets, output shafts, housings, and torque ratings. The only difference is the input configuration. Use this comparison to select the right input type for your application.
| Feature | EP-NRV090 (Solid Shaft Input) | EP-NMRV090 (IEC Flange Input) |
|---|---|---|
| Input Connection | Solid shaft — coupling, pulley, sprocket | Hollow bore with IEC motor flange |
| Motor Mounting | No motor flange — flexible drive layout | Direct motor mounting via IEC flange |
| Best Application | Gear trains, belt/chain drives, multi-stage systems | Direct motor-to-gearbox mounting |
| Housing Material | Die-cast aluminium A360 | Die-cast aluminium A360 (same body) |
| Output Torque | Up to 5000 Nm (identical) | Up to 5000 Nm (identical) |
| Drive Train Length | Shorter — no motor/adaptor overhang | Slightly longer with motor mounted |
| Corrosion Resistance | Excellent — same aluminium housing | Excellent — same aluminium housing |
| IP Rating | IP65 shaft seals standard | IP65 shaft seals standard |
| Noise Level | Low — same worm set | Low — same worm set |
| Weight | ~16 kg | ~16 kg (same) |
Application Sectors — EP-NRV090
The EP-NRV090 solid-shaft worm gearbox is suited to the following industries and drive system types, each benefiting from direct shaft coupling without a motor flange.
⚘ Mining Conveyor Gear Trains
Suitable heavy duty NRV worm gearbox mining conveyor.
⚙ Crane Drive Systems
Suitable solid shaft worm reducer crane drive system.
⚚ Extruder Shaft Drives
Suitable shaft input worm gearbox extruder drive.
⚒ Large Shaft Pumps
Suitable NRV worm gearbox large shaft pump.
⚛ Heavy Agitators
Suitable heavy solid shaft worm reducer agitator.
Selection Guide, Mounting Positions & Shaft Details
How to Select the Correct Ratio
- Calculate required output torque: M₂ = 9,550 × P (kW) / n₂ (rpm), then multiply by service factor (fs = 1.0–2.5).
- Determine actual input shaft speed: For belt/chain drives, n_input = n_motor × (D_motor pulley / D_NRV pulley). Use this as your input speed, not the motor rated speed.
- Find your ratio: i = n_input / n_output. Select the closest available ratio from 7.5–100:1.
- Confirm torque capacity: The selected ratio’s rated torque must exceed M₂ × fs. If not, step up to EP-NRV110.
- Check input shaft radial load: Calculate belt/chain tension force and verify it does not exceed Fri max = 1270 N.
Input & Output Shaft Details
Input shaft: 28 mm solid | Keyway: 8×4.0 mm | Tolerance: h6 | Max radial load: 1270 N
Mount couplings, pulleys, and sprockets directly. Use a keyway-secured locking collar or hub to prevent axial movement. Calculate input shaft radial load from belt/chain tension and verify against Fri max = 1270 N.
45 mm diameter with keyway. Single-sided. Default supply.
Shaft exits both sides. Bidirectional take-off. Suffix: DZ.
Direct bolt-on flange connection. Eliminates coupling. Suffix: FL.

Mounting Positions

| Position | Description | Shaft Orientation | Oil Level Note |
|---|---|---|---|
| B3 | Horizontal foot mount | Horizontal | Standard fill level — default factory supply |
| B6 | Foot mount, output shaft down | Vertical downward | Reduce oil by ~15% |
| B7 | Foot mount, output shaft up | Vertical upward | Increase oil by ~15% |
| B8 | Foot mount, output shaft horizontal (180°) | Horizontal reversed | Standard fill level |
| V5 | Flange mount, shaft down | Vertical downward | Reduce oil — check lubrication guide |
| V6 | Flange mount, shaft up | Vertical upward | Increase oil — check lubrication guide |
Frequently Asked Questions — EP-NRV090
▶ What shaft-coupled applications suit the EP-NRV090?
The EP-NRV090 excels in shaft-coupled mining conveyor gear trains, overhead crane long-travel drives, heavy extruder secondary drives, and large industrial pump shafts. Its 28 mm solid input shaft and 5,000 Nm output torque capacity accommodate heavy-duty shaft drives without a motor flange.
▶ What is the input shaft diameter and maximum radial load for the EP-NRV090?
The EP-NRV090 features a 28 mm solid input shaft with an 8×4.0 mm keyway. Maximum input shaft radial load (Fri max) is 1,270 N. For applications approaching this limit, a bearing support bracket on the input shaft is recommended.
▶ How does the EP-NRV090 save weight versus cast iron in crane drive applications?
At approximately 16 kg, the NRV090 is 30–40% lighter than a comparable cast iron worm gearbox. On elevated crane bridge structures, this weight reduction simplifies structural design and eases on-site installation — particularly for multi-gearbox crane end carriage assemblies.
▶ What is the self-locking behaviour of the EP-NRV090 at high ratios?
Static self-locking (η < 0.5) is achieved at gear ratios of 40:1 and above. This prevents output shaft back-drive under static load — useful for inclined conveyor and crane applications. Dynamic self-locking is not guaranteed; add a certified holding brake for safety-critical load retention.
▶ Can the EP-NRV090 run 24 hours a day in a mining environment?
Yes, provided the correct service factor is applied (fs ≥ 1.6 for 24-hour uniform load). Specify Viton shaft seals for abrasive mining dust environments and use synthetic ISO VG 220 oil for extended oil change intervals (up to 10,000 hours with synthetic oil).
▶ What is the oil capacity of the EP-NRV090?
The EP-NRV090 holds approximately 1.5 litres of worm gear oil in B3 horizontal orientation. Use ISO VG 220 worm gear oil. Change oil every 5,000 hours (mineral) or 10,000 hours (synthetic). Verify fill level matches the selected mounting position from the lubrication guide.
Customer Reviews

★★★★★
“EP-NRV090 units installed in the drive gear trains of our underground coal conveyor systems. Solid shaft input couples directly to the primary gearbox output without a motor adaptor, shortening the drive train and reducing installation complexity. Weight saving is a real bonus underground where every kilogram counts.”
Wayne Cooper — Mining Conveyor Solutions
Australia
★★★★★
“Specified for the final reduction stage in our heavy overhead crane long-travel drives. Self-locking at 50:1 provides static load holding between travel commands. Two years of demanding port operations without a single failure.”
Peter Müller — Crane Drive Systems AG
Germany
★★★★★
“Running on large shaft-driven pump drives at our water distribution facility. The 28 mm solid input shaft handles the belt tension loads from our primary drive pulley without any bearing wear issues. Excellent corrosion resistance in the humid coastal environment.”
Amara Diop — Industrial Pump Engineering
Ivory Coast
Related Products & Accessories
⚙ Input Connection Options
Flexible jaw couplings and disc couplings for 28 mm solid shaft.
Chain sprockets and V-belt pulleys (calculate Fri against 1270 N max).
Toothed-belt pulley (verify radial load).
Bearing support bracket for high-tension chain/belt drives.
⚒ Output Accessories
■ Single solid output shaft (standard, 45 mm)
■ Double bidirectional shaft (DZ)
■ Output flange (FL)
■ Torque arm for torque reaction mounting
■ Dust cover for unused shaft end
◆ Related Series
■ EP-NMRV090 — hollow bore IEC flange input variant
■ EP-NRV-E090 — solid input, coaxial inline output
■ EP-NMRV-E090 — IEC flange input, coaxial output
■ EP-NRV110 — next frame size up
Ready to Order the EP-NRV090?
Request a quote, technical selection support, or enquire about OEM and distributor partnership opportunities for Australian and international markets.
▼ Distributor & OEM partnerships welcome — volume pricing available

