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-F87 Parallel-Shaft Helical Gear Reducer
The EP-F87 is a 3-stage parallel-shaft helical gear reducer delivering up to 3,000 N·m output torque from 0.37–22 kW across gear ratios 4.92–73.34. Available in foot-mount (F), flange-mount (FF), hollow-bore (FA), flange+hollow (FAF), and torque-arm (FAT) configurations — engineered for quiet, efficient, long-service industrial drive applications.
MOQ: flexible. Minimum order value USD 1,500; mixed orders and trial quantities welcome.
Product Overview — EP-F87 Parallel-Shaft Helical Gear Reducer
The EP-F87 parallel-shaft helical gear reducer targets the heavy sector of the market: mining feeders, recycling shredder pre-feeds, power station coal-handling conveyors, and construction aggregate drives. With up to 3,000 N·m output torque from 0.37–22 kW inputs and ratios spanning 4.92–73.34, the three-stage gear train is engineered to absorb the shock loading that characterises these applications without fatigue cracking or surface distress.
Gear tooth geometry is optimised for contact ratio above 1.9, ensuring that at least two tooth pairs share the load at all times. Combined with case-hardened and precision-ground tooth flanks, this produces a gear mesh that tolerates momentary overloads to 2.5× rated torque — a margin adequate for most jam and start events in heavy material-handling. Learn more about our manufacturing standards on the Ever Power quality page.
The EP-F87 housing is robustly ribbed to resist deflection under extreme radial shaft loads, maintaining gear mesh alignment and bearing positions even during high-inertia stopping events. Oil sight-glass and magnetic drain plug are standard, supporting routine preventive maintenance without oil analysis equipment.
Technical Specifications — EP-F87
| Parameter | Specification |
|---|---|
| Gear Type | Multi-stage parallel-shaft helical gears, precision-ground DIN 6/ISO 6 |
| Number of Stages | 3-stage |
| Motor Power Range | 0.37–22 kW |
| Max Output Torque | 3,000 N·m |
| Gear Ratio Range | 4.92–73.34 |
| Output Speed Range | 20–285 rpm |
| Approximate Unit Weight | 60–90 kg |
| Max Output Radial Load | 19,500 N |
| Transmission Efficiency | ≥ 96% per stage (overall ≥ 92% for 2-stage, ≥ 88% for 3-stage) |
| Lubrication | Splash lubrication; ISO VG 220 mineral oil (factory fill) |
| Housing Material | Close-grained cast iron (HT250 / EN-GJL-250) |
| Gear Material | Case-hardened alloy steel (20CrMnTi / 20MnCr5), HRC 58–62 |
| Protection Rating | IP55 standard; IP65 optional |
| Ambient Temperature | −25 °C to +45 °C (standard lubricant) |
| Noise Level | ≤ 72 dB(A) at rated load (1 m, free-field) |
| Standards Compliance | ISO 6336, DIN 3990 gear rating; ISO 281 bearing life; CE Machinery Directive |
Structural Types & Mounting Configurations — F87 Series
The F87 series is available in multiple structural types to suit different installation geometries and driven-machine interfaces. All types share the same internal gear set and achieve identical torque and efficiency ratings; the differences lie in mounting method and output connection.
| Type Code | Description |
|---|---|
| F87 | foot-mounted, solid output shaft |
| FF87 | B5 flange-mounted, solid output shaft |
| FA87 | shaft-mounted, hollow output shaft |
| FAF87 | B5 flange + hollow output shaft |
| FAT87 | torque-arm, hollow output shaft |
Mounting Positions M1–M6
All F87 structural types support six standard mounting positions (M1 through M6), defined by the angular orientation of the output shaft relative to the horizontal. Oil fill level and vent plug position must be adjusted for each mounting position; refer to the installation manual for position-specific fill quantities and the correct vent-plug orientation.
Key Advantages of the EP-F87
High Transmission Efficiency
Each gear stage delivers ≥96% mechanical efficiency through precision-ground helical flanks and optimised tooth profile corrections. Compared with worm reducers of equivalent output torque, the EP-F87 typically saves 15–35% in electrical energy over the same duty cycle — a saving that often exceeds the gearbox purchase price within two years.
High Torque Density
With up to 3,000 N·m from a housing sized for 0.37–22 kW, the EP-F87 achieves torque density competitive with bevel-helical units of the same output-shaft diameter. The case-hardened alloy-steel gears (HRC 58–62) sustain high Hertzian contact stress without case fatigue, enabling compact dimensions even at the upper end of the power range.
Long, Predictable Service Life
Bearings are selected for a minimum L10h life of 20,000 hours at rated conditions and verified by ISO 281 calculation using actual application load spectra. Precision-ground gears eliminate the geometric errors that cause micro-pitting, extending tooth-flank life to typically 40,000 hours or more when correctly lubricated.
Multiple Structural Types
Five standard structural types — F, FF, FA, FAF, FAT — and an input-shaft-only FA-SZ variant address virtually every machine interface geometry without custom engineering. The FA and FAT hollow-bore types eliminate external couplings entirely, reducing drivetrain length and eliminating one routine maintenance item.
Low Noise & Low Vibration
Helical gear engagement produces a progressive, distributed contact zone rather than the sudden full-face mesh of spur gears. This characteristic, combined with profile-ground tooth flanks and dynamically balanced rotating components, keeps noise levels below 72 dB(A) at 1 m — important in operator-occupied environments and buildings with vibration-sensitive equipment.
Compact Inline Layout
The parallel-shaft geometry keeps the overall drive envelope short in the radial direction, allowing direct-couple installation in machine frames where right-angle units would require a longer cantilevered arrangement. The F87's small envelope also reduces the inertia of the stationary drive assembly, which matters in frequent-cycle indexing applications.
Structural Type Diagrams — F87 Series
The diagrams below show the external geometry and connection interfaces for each structural type in the F87 family. Use these to confirm mounting space requirements and driven-machine interface compatibility before finalising your order.
F87 Standard Foot-Mount (Solid Output Shaft)
FF87 Flange-Mount (Solid Output Shaft)
FA87 Shaft-Mounted (Hollow Output Bore)
FAF87 Flange + Hollow Bore
FAT87 Torque-Arm (Hollow Bore)
FA87-SZ Input Shaft Only
Industry Applications — Where the EP-F87 Excels
| Industry Sector | Typical Application |
|---|---|
| Mining & Quarrying | Apron feeder drives, screen vibrator-drive gearboxes, and filter-press plate-shifter units. |
| Power Generation | Ash-handling screw conveyor drives and coal-spreader-stoker auxiliary drives. |
| Recycling Plants | Shredder pre-feed conveyors, eddy-current separator drums, and baler infeed drives. |
| Construction Machinery | Concrete batch plant aggregate conveyor head-end drives. |
Application Case Study: Coal Mine Apron Feeder
An open-cast coal mine equipped its ROM pad apron feeder with an EP-F87 paired with a 15 kW motor and a ratio of 58:1. The unit withstood continuous coal dust, shock loading at 2.8× rated torque, and ambient temperatures from −15 °C to +45 °C over a 30-month trial period without a single seal replacement.
Model Designation Guide — How to Order an EP-F87
The model code contains all ordering information required for production. An example order code for a torque-arm, hollow-bore, 7.5 kW unit is:
EP - F87 - FAT - Y - 3 - 7.5 - 4P - M1
| Code Element | Meaning |
|---|---|
| EP | Brand identifier — Ever Power |
| F87 | Series and frame size |
| FAT | Structural type: torque-arm, hollow-bore output |
| Y | Motor type: Y-series IEC standard induction motor |
| 3 | Number of gear stages |
| 7.5 | Motor rated power in kW |
| 4P | Motor pole count (1,450 rpm at 50 Hz) |
| M1 | Mounting position |
Frequently Asked Questions — EP-F87
Built for Harsh Environments — Available Worldwide
From open-cast mines to offshore platforms, the EP-F87 is specified by engineers who cannot afford drivetrain downtime. Read about Ever Power's quality assurance programme, or contact us directly to request a factory test certificate and dimensional drawing for your project.
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