Audible noise is evidence to investigate, but fault location depends on whether the sound tracks speed, torque or the machine structure.
Helical Gearbox Noise Diagnosis by Speed and Load
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EP-R77 Helical Gearmotor – 3-Stage Inline Gear Speed Reducer
The EP-R77 helical gear reducer reaches up to 1,600 Nm output torque with a radial load rating of 12,350 N—suitable for heavy-duty bulk handling conveyors, large industrial fans, and cement plant drives. IP55. MOQ: 1–5 sample units; mixed orders from ~USD 1,500; lead time 10–25 working days.
EP-R77 Helical Gearmotor – 3-Stage Inline Gear Speed Reducer
The EP-R77 inline helical gear reducer is the frame-77 model in Ever Power's industry-proven R-series inline helical gearmotor lineup. Designed for demanding industrial applications that require reliable, high-efficiency speed reduction with multi-orientation mounting flexibility, the EP-R77 delivers maximum output torque of 1600 Nm and supports permitted radial loads up to 12,350 N N. Motor power compatibility spans from 0.12 kW through high-power configurations, with gear ratios ranging from i = 3.57 to i = 195.24. The EP-R77 is the natural choice for heavy industry, bulk material handling, large fans applications where performance, compactness, and low maintenance cost are all priorities. Browse the complete Ever Power gear reducer range or contact us for a tailored application review.
The EP-R77's high-capacity output bearings support radial loads up to 12,350 N—among the highest in the compact inline helical category—enabling direct coupling of large-diameter sprockets and pulleys without outboard bearing structures.
EP-R77 — standard foot-mount (R) inline helical gear reducer
Available Configurations
R77
Foot-mount, solid output shaft. Standard horizontal installation for conveyor, mixer, and industrial drives.
Foot-mount, solid output shaft. Standard horizontal installation for conveyor, mixer, and industrial drives.
RF77
Flange-mount output variant. The flanged housing mates directly to the driven machine's input face for alignment-free installation.
Flange-mount output variant. The flanged housing mates directly to the driven machine's input face for alignment-free installation.
R77 with Pre-stage
Two or three-stage combinations extending gear ratio coverage while maintaining the EP-R77 output shaft dimensions. Contact Ever Power for specific pre-stage options.
Two or three-stage combinations extending gear ratio coverage while maintaining the EP-R77 output shaft dimensions. Contact Ever Power for specific pre-stage options.
Technical Specifications
| Parameter | Value / Range |
|---|---|
| Frame Size | 77 |
| Motor Power Range | 0.12 kW – 160 kW (config.) |
| Gear Ratio (i) | 3.57 – 195.24 |
| Max Output Torque | 1600 Nm |
| Gear Unit Weight (foot/flange) | 38–46 kg / 44–52 kg |
| Max Permitted Radial Load | 12,350 N N |
| Mounting Positions | M1 – M6 |
| Lubrication | Synthetic gear oil, sealed for life |
| Protection Class | IP55 standard |
| Transmission Efficiency | > 96% per stage |
| Housing Material | Cast iron / die-cast aluminium |
Selection Parameter Table – EP-R77
| Output Speed / Input Speed [rpm] | Output Torque [Nm] | Gear Ratio i | Radial Load [N] | Service Factor fB | Model |
|---|---|---|---|---|---|
| 411 | 11 | 3.52 | 11970 | 2.45 | R77 |
| 356 | 14 | 4.07 | 12160 | 2.45 | R77 |
| 333 | 14 | 4.35 | 12160 | 2.60 | R77 |
| 288 | 18 | 5.03 | 12255 | 3.00 | R77 |
| 253 | 20 | 5.73 | 12350 | 3.40 | RF77 |
| 173 | 29 | 8.38 | 12350 | 5.00 | RF77R37 |
Mounting Positions M1–M6
Available mounting positions M1–M6 for the R-series (foot-mount models)
M1: Output shaft horizontal right — standard for conveyor and pump drives.
M2: Output shaft horizontal left — mirror-image installation.
M3: Shaft downward — agitators, thickener rakes, screw conveyors.
M4: Shaft upward — overhead drives, fan towers, elevated conveyors.
M5: Horizontal motor, angled shaft down — compact side-entry layouts.
M6: Horizontal motor, angled shaft up — inclined conveyor and upward feed drives.
Model Number Explanation
Model number designation — Ever Power R-series inline helical gearmotor
| Code Element | Meaning | Example |
|---|---|---|
| R | Inline helical gear series | R |
| F (optional) | Flange output; absent = foot mount | RF77 |
| 77 | Frame size designation | R77 |
| Pre-stage suffix | Additional gear stage for extended ratio | R77R77 |
Industry Applications
Heavy Conveyor Systems
Belt conveyors, apron conveyors, and bucket elevators in mining, quarrying, and bulk material handling facilities specify the EP-R77 for its high radial load capacity and reliable sealed lubrication.
Belt conveyors, apron conveyors, and bucket elevators in mining, quarrying, and bulk material handling facilities specify the EP-R77 for its high radial load capacity and reliable sealed lubrication.
Industrial Mixing & Processing
Reactor agitators, thickener rake drives, and large mixer drives benefit from the EP-R77's high starting torque and consistent speed characteristics under variable-viscosity loads.
Reactor agitators, thickener rake drives, and large mixer drives benefit from the EP-R77's high starting torque and consistent speed characteristics under variable-viscosity loads.
Heavy Industry, Bulk Material Handling, Large Fans
Applications in heavy industry, bulk material handling, large fans environments rely on the EP-R77 for its combination of output torque, sealed maintenance-free operation, and multi-orientation mounting flexibility.
Applications in heavy industry, bulk material handling, large fans environments rely on the EP-R77 for its combination of output torque, sealed maintenance-free operation, and multi-orientation mounting flexibility.
Customer Case Studies
USA · Bulk Material Handling
★★★★★
A bulk material terminal in Texas installed EP-R77 gearmotors on their reclaim conveyor tail drives. The 12,350 N radial load rating allowed direct troughing-belt conveyor drives without bearing stands. "We consolidated our drive inventory—the R77 replaces two previous units that each required external bearing support. Installation labour dropped by 40% per drive, and we've had zero gearbox failures in 22 months of 24/7 operation."
UK · Cement Industry
★★★★★
A UK cement plant uses EP-R77 drives on their coal mill feed conveyors. The units must handle frequent start/stop cycles under full load. "We specified service factor fB 2.5 at the selection stage and the EP-R77 met it without issue. Thermal performance was better than the datasheet suggested—we measured 44°C surface temperature versus a calculated 52°C under continuous full-load cycling."
Russia · Woodworking Plant
★★★★☆
A Siberian lumber processing plant fitted EP-R77 units to their log-turning conveyors. Arctic winter conditions down to –25°C were a key consideration. "The synthetic lubrication in the EP-R77 starts reliably even at –20°C ambient without pre-heating. We've replaced our previous units that required oil-bath pre-heaters in winter—simplifying our cold-start procedures significantly."
Frequently Asked Questions
Why Specify the EP-R77 from Ever Power?
Ever Power delivers the EP-R77 inline helical gear reducer with full application engineering support, including selection assistance, 3D CAD data, dimensional drawings, and post-delivery commissioning guidance. Our technical team has experience across the industries described above and can advise on motor pairing, mounting configuration, and service factor selection for your specific application. Visit the Ever Power company page to learn more about our engineering approach, or go straight to the contact page to reach our technical sales team.
Request EP-R77 Pricing, Datasheets & Application Support
Tell us your speed, torque, mounting, and environment requirements. Sample orders and mixed-model inquiries welcome.
Blogs Updated
Coupling Alignment for Inline Helical Gearbox Installations
Flexible couplings accommodate limited relative movement, but poor shaft alignment still affects bearings and seals.
Helical Gearbox Oil Leak Diagnosis and Seal Protection
Oil observed on a housing may have traveled from a vent, joint or shaft seal; finding the first wet point is essential.