Audible noise is evidence to investigate, but fault location depends on whether the sound tracks speed, torque or the machine structure.
EP-S87 Helical-Worm Gear Reducer
The EP-S87 is a 2 (1 helical + 1 worm) helical-worm gear reducer with right-angle output, delivering up to 2,100 N·m from 0.37–11 kW across gear ratios 8.74–196.11. Available in foot-mount (S), flange-mount (SF), hollow-bore (SA), flange+hollow (SAF), and torque-arm (SAT) configurations — quieter and more efficient than conventional worm reducers.
MOQ: flexible. Minimum order value USD 1,500; mixed orders and trial quantities welcome.
Product Overview — EP-S87 Helical-Worm Gear Reducer
Heavy packaging lines, textile mill drives, and construction equipment auxiliary units require a right-angle gear reducer that can absorb shock, handle continuous torque, and stay compact enough to fit within demanding machine envelopes. The EP-S87 helical-worm gear reducer addresses this need with up to 2,100 N·m continuous output torque from 0.37–11 kW and ratios spanning 8.74–196.11 — making it the most capable mid-heavy unit in the S-series.
The worm wheel of the EP-S87 is manufactured from centrifugally cast phosphor-bronze, a process that produces a homogeneous, pore-free alloy microstructure particularly resistant to pitting under fluctuating hertzian contact stress. Combined with the hardened worm shaft and synthetic lubricant film, this material selection supports a peak shock torque of 2.5× rated continuous torque — adequate for capping machine jams, palletiser layer-push events, and mortar mixer start-up surges.
The SA87-SZ (input-shaft-only) variant of the EP-S87 fills a specific niche: machinery where the drive motor cannot be directly coupled, such as a HVAC fan with variable-belt speed adjustment, a diesel-engine PTO drive, or a hydraulic-motor gear connection. Our applications team holds stock of SA-SZ input adaptor kits for common belt-drive configurations.

Technical Specifications — EP-S87
| Parameter | Specification |
|---|---|
| Gear Type | Helical pre-stage + worm gear set (right-angle output) |
| Number of Stages | 2 (1 helical + 1 worm) |
| Motor Power Range | 0.37–11 kW |
| Max Output Torque | 2,100 N·m |
| Gear Ratio Range | 8.74–196.11 |
| Output Speed Range | 7–161 rpm |
| Approximate Unit Weight | 70–105 kg |
| Max Output Radial Load | 18,500 N |
| Overall Efficiency | 75–82% (vs 55–65% for equivalent single-stage worm) |
| Lubrication | Oil bath; ISO VG 220 synthetic-blend worm gear oil (factory fill) |
| Housing Material | Close-grained cast iron (HT250) |
| Worm Shaft Material | 20CrMnTi alloy steel, case-hardened HRC 58–62, profile ground Ra ≤ 0.4 µm |
| Worm Wheel Material | Centrifugally cast phosphor-bronze (ZCuSn10P1) |
| Helical Stage Material | 20CrMnTi alloy steel, case-hardened, precision ground DIN 6 |
| Protection Rating | IP55 standard; IP65 optional |
| Ambient Temperature | −25 °C to +40 °C (standard lubricant) |
| Noise Level | ≤ 68 dB(A) at rated load (1 m, free-field) |
| Standards Compliance | ISO 14521 worm gear rating; ISO 281 bearing life; CE Machinery Directive |
Structural Types & Mounting Configurations — S87 Series
The S87 series is produced in five structural types plus an input-shaft-only SA-SZ variant. All share the same internal helical-worm gear train and achieve identical output torque and efficiency ratings. The structural type determines the mounting method and driven-machine interface.
| Type Code | Description |
|---|---|
| S87 | foot-mounted, solid output shaft |
| SF87 | B5 flange-mounted, solid output shaft |
| SA87 | shaft-mounted, hollow output bore |
| SAF87 | B5 flange + hollow output bore |
| SAT87 | torque-arm, hollow output bore |
| SA87-SZ | input shaft only, no motor flange |

SF and SAF Mounting Positions
Flange-mounted SF87 and SAF87 variants support all six standard mounting positions. Oil fill level and breather plug position must be adjusted per mounting position — refer to the position-specific lubrication table in the installation manual.

SA and SAT Torque-Arm Mounting Positions
The SA87 shaft-mounted and SAT87 torque-arm variants mount directly onto the driven shaft, reacting torque through the torque arm rather than a baseplate. This eliminates shaft-to-shaft coupling alignment and is particularly suited to conveyor head drives and drum agitators.

Key Advantages of the EP-S87 Helical-Worm Reducer
The helical input stage of the EP-S87 achieves ≥98% per-stage efficiency, contributing directly to the 75–82% overall efficiency of the complete unit — 15–25 percentage points above conventional single-stage worm reducers. In continuous-duty applications this margin translates to measurable energy cost reduction and lower operating heat, reducing cooling requirements and extending lubricant life.
The S-series right-angle configuration delivers 2,100 N·m from a housing sized for 0.37–11 kW — a torque density comparable to much larger parallel-shaft units. The perpendicular input-to-output layout is inherently suited to machine geometries where the motor and driven shaft cannot share the same axis, eliminating additional bevel stages or chain-and-sprocket drives that add cost and maintenance.
By pre-reducing speed in the helical stage before it reaches the worm mesh, the EP-S87 reduces worm sliding velocity at any given overall ratio. Lower sliding velocity directly reduces worm-mesh friction noise, yielding typical noise levels 6–10 dB(A) below equivalent single-stage worm reducers — an advantage valued in food production halls, pharmaceutical facilities, and any environment with operator occupancy near the drive.
Ratios from 8.74 to 196.11 in a single housing are achievable with the EP-S87, covering applications from moderately fast conveyor drives at the lower end to very slow-rotation stirring and positioning drives at the upper end. This breadth eliminates the need to cascade multiple reducers in most applications, simplifying the drivetrain and reducing total installation length.
Five structural types — S, SF, SA, SAF, SAT — plus the SA-SZ input shaft variant address every practical machine interface without custom engineering. SA and SAF hollow-bore types allow direct shaft mounting, eliminating flexible couplings and their associated alignment requirements. The SAT torque-arm type simplifies drum and conveyor installations further by reacting torque through a single rubber-buffered arm rather than a rigid baseplate.
The EP-S87 worm wheel is manufactured from centrifugally cast phosphor-bronze (ZCuSn10P1), chosen for its combination of high load capacity, low friction against hardened steel, and resistance to adhesive wear under boundary-lubrication conditions during start-up. The hardened and profile-ground worm shaft (Ra ≤ 0.4 µm) maintains an elastohydrodynamic oil film across the full operating speed range, extending tooth-surface life to typically 25,000–40,000 hours.
Structural Type Diagrams — S87 Series
Use the diagrams below to confirm the external geometry, mounting interface, and connection dimensions of each S87 structural type before finalising your machine design. Certified dimensional drawings in DXF and PDF are available on request.
S87 Foot-Mount, Solid Output Shaft
SF87 B5 Flange, Solid Output Shaft
SA87 Shaft-Mounted, Hollow Bore
SAF87 B5 Flange + Hollow Bore
SAT87 Torque-Arm, Hollow Bore
SA87-SZ Input Shaft Only
Industry Applications — Where the EP-S87 Excels
| Industry Sector | Typical Application |
|---|---|
| Heavy Packaging Lines | Case palletiser layer-forming turntables, stretch-wrapper pre-stretch drives, and shrink-tunnel conveyor drives. |
| Mining Auxiliaries | Sample crusher feed drives, laboratory jaw-mill auxiliary drives, and sample conveyor take-offs. |
| Textile Mill | Slubbing frame drafting roll drives, warp beam tension control drives, and loom shed motion auxiliary drives. |
| Construction Equipment | Concrete pump mixer paddle drives and portable mortar mixer drum drives. |
Application Case Study: Stretch-Wrapper Pre-Stretch Unit
A pallet wrapping machine OEM switched from a dedicated worm-only gearbox to an EP-S87 on its pre-stretch film carriage. Efficiency improved from 58% to 76%, allowing the motor to be downsized from 0.75 kW to 0.55 kW with no reduction in wrap force. The OEM now specifies EP-S87 as standard on its full machine range, with 340 units shipped in the first year.
Model Designation Guide — How to Order an EP-S87
Every element of the S-series order code defines a specific product attribute. The example below shows a 1.5 kW, torque-arm, hollow-bore unit in mounting position M1:
EP - S87 - SAT - Y - 2 - 1.5 - 4P - M1
| Code Element | Meaning |
|---|---|
| EP | Brand identifier — Ever Power |
| S87 | Series and frame size — S-series helical-worm |
| SAT | Structural type: torque-arm, hollow-bore output |
| Y | Motor type: Y-series IEC standard induction motor |
| 2 | Number of gear stages (helical + worm) |
| 1.5 | Motor rated power in kW |
| 4P | Motor pole count (1,450 rpm at 50 Hz) |
| M1 | Mounting position (1 of 6 standard positions) |

Frequently Asked Questions — EP-S87
EP-S87 — The Packaging and Heavy-Industry Drive of Choice
Machine builders and end users across the packaging, textile, and construction sectors rely on the EP-S87 for its torque density, quiet operation, and low maintenance profile. We offer OEM volume pricing, custom-painted units, and dedicated after-sales technical support. Visit the contact page to request a quotation tailored to your production volume.
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