WPA Series Single Standard Worm Gear Reducer

WPA Series Single Standard Worm Gear Reducer

Foot-mounted cast iron right-angle worm gear reducers, covering sizes 40–155, with speed ratios ranging from 10:1 to 60:1 and output torque up to 900 N·m. These units serve as direct replacements for the SEW-Eurodrive WA series, Motovario TA/TR series, and Rossi MW series, and are utilized in Australia for conveyors, mixers, agricultural irrigation systems, and oven chain drive mechanisms.

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Description

Across Australian manufacturing — from bottling plants in Melbourne to grain handling facilities in regional Queensland — the WPA Series worm gear reducer is the standard foot-mounted right-angle drive unit that maintenance engineers specify as the first choice when reliability, dimensional compatibility, and value all matter simultaneously. Covering centre distances from size 40 (0.09 kW, 3.8 kg) through to size 155, with gear ratios from 10:1 to 60:1 and output torques reaching over 900 N·m, the WPA delivers dependable slow-speed torque transmission in a cast-iron foot-mount housing that is dimensionally compatible with the most widely deployed worm reducers in Australian industry — including SEW-Eurodrive WA series, Motovario TA/TR, and Rossi MW foot-mount units. Manufactured to ISO 9001:2015, designed per AGMA 6034, and supplied with full engineering support from Ever-Power Worm Gear Reducer Co., Ltd. (Australia), 27 Harley Crescent, Condell Park NSW 2200.

Key Specifications & Parameters — WPA Series Worm Gear Reducer

Complete dimensional and performance data for all standard WPA frame sizes. Design references: ISO 9001:2015, AGMA 6034 rated torque methodology, DIN 3975 gear quality specification.

Size Input Power (kW) Ratio Range Centre Dist. A (mm) Overall Length B (mm) Output Shaft LS (mm) Weight (kg)
40 0.09 10:1 – 60:1 142 112 28 3.8
50 0.17 10:1 – 60:1 175 145 40 7
60 0.23 10:1 – 60:1 195 165 50 10.5
70 0.50 10:1 – 60:1 234 195 60 14.5
80 0.70 10:1 – 60:1 264 210 65 22
100 1.5 10:1 – 60:1 322 245 75 36
120 3.0 10:1 – 60:1 385 285 85 63
135 5.5 10:1 – 60:1 435 320 95 80
155 7.5 10:1 – 60:1 507 387 110 114

What Is the WPA Series Worm Gear Reducer?

WPA worm gear reducer cast iron housing and worm mesh detail

The WPA series is the standard single-stage foot-mount configuration of the WP worm reducer family. In the model designation, W identifies the worm-gear-worm reducer family, P indicates the box structure (either integral or split-housing), and A denotes the foot-mount base plate configuration — a fixed cast-iron base with four mounting holes drilled to standard bolt-circle dimensions that are dimensionally interchangeable with the most common competing brands used across Australian industry.

Inside the housing, the worm shaft is machined from 20CrMnTi alloy steel, carburised to a case depth of 0.8–1.2 mm, and quenched to a surface hardness of HRC 56–62. The worm wheel is hobbed from tin-bronze (ZCuSn10Pb1), providing the 5:1 hardness ratio between worm and wheel that AGMA 6034 identifies as optimal for maximising bronze gear wear life under sliding contact. The solid output shaft is manufactured from 45# chromium steel in h6 shaft tolerance per DIN 748, accepting standard keyway-and-setscrew couplings, sprockets, and pulleys without any additional machining. Worm thread profile accuracy is produced to DIN 3975 Class 8 or better, ensuring smooth mesh engagement and low noise operation at rated load.

The WPA series offers inherent self-locking at ratios of 20:1 and above, where the worm lead angle falls below the effective friction angle of approximately 6°. At these ratios, a static output load cannot back-drive the worm shaft — a property widely used in Australian hoist, gate-valve, and positioning drive applications. For ratios of 10:1 and 15:1, self-locking is not reliable and a supplementary brake should be specified for gravity-loaded applications, as required under Australian Standard AS 4024 machinery guarding guidelines.

WPA Series Configurations and Shaft Variants

While the WPA designates the base foot-mount configuration, a range of input and output shaft variants is available within the same housing envelope:

Variant Code Output Configuration Input Configuration Best Application
WPA (standard) Solid shaft, single side Single solid input shaft Conveyors, mixers, agitators
WPDA (dual input) Solid shaft, single side Dual input shaft access (both ends) Encoder mount, manual override
WPA + flange input Solid shaft, single side IEC B14/B5 motor flange Direct motor mount, no coupling
WPA-X (double output) Double-extended output shaft Single input Twin-sprocket drives

WPA worm gear reducer output shaft foot mount base view
WPA worm gear reducer complete assembly side view

Manufacturing Process: How WPA Quality Is Built In

The WPA series is produced under a documented ISO 9001:2015 quality management system. The following process controls are applied at each stage of manufacture:

  1. Material Certification: Every batch of 20CrMnTi worm shaft bar stock and ZCuSn10Pb1 bronze wheel billets is spectrographically verified for alloy composition against the material certificates required by AGMA 6034.
  2. Housing Casting & Machining: GG25 grey-iron housings are cast in permanent metal moulds for dimensional repeatability. All bearing bores, shaft holes, and mounting face surfaces are CNC-machined to H7 tolerance. Bolt pattern dimensions are held to ±0.05 mm to ensure direct interchange with competitor units using the same nominal bolt circle.
  3. Worm Thread Grinding: After case-hardening, the worm thread flanks are precision-ground on dedicated CNC worm-grinding centres to DIN 3975 Class 8 accuracy. Surface roughness on the active flank is Ra ≤ 0.8 μm — the threshold at which full hydrodynamic oil film formation at the worm-bronze interface is achievable at rated sliding speed.
  4. Worm Wheel Hobbing: Bronze wheel blanks are finish-hobbed in a single operation matched to the specific worm profile to ensure conjugate tooth contact geometry, minimising contact stress concentration at the tooth edges.
  5. Run-In Testing: Each assembled WPA undergoes a no-load run-in at rated speed, followed by a loaded run-in at 50% rated torque. Housing surface temperature and vibration are recorded. Units exceeding 72 dB(A) noise or 4.5 mm/s RMS vibration are quarantined for root-cause investigation before release.
  6. Painting & Corrosion Protection: Cast-iron housings receive zinc-phosphate pre-treatment followed by a two-coat epoxy paint system. Salt-spray resistance exceeds 500 hours per ISO 9227, suitable for Australian coastal industrial environments in Sydney, Newcastle, and Wollongong.

How to Select the Right WPA Frame Size — Step-by-Step Guide

  1. Determine Required Ratio: Divide motor speed (1,450–1,500 rpm for 4-pole, 50 Hz Australian mains) by required output shaft speed. Select nearest standard WPA ratio: 10, 15, 20, 25, 30, 40, 50, or 60.
  2. Calculate Design Torque: T_design = (Motor kW × 9,550 / Output rpm) × Service Factor. Use SF 1.25 for smooth continuous loads (conveyors, agitators), SF 1.5 for moderate shock (packaging, augers), SF 2.0 for heavy shock (stone crushers, impact feeders). Identify the smallest WPA frame size where rated output torque ≥ T_design.
  3. Verify Thermal Rating: Confirm the thermal rated input power for your frame size meets or exceeds your motor shaft power. For continuous duty in Queensland and Western Australian summer conditions (ambient 35–45 °C), derate the thermal power limit by 10% per 10 °C above the 20 °C datasheet reference temperature. If marginal, specify synthetic ISO VG 220 lubricant (improves thermal performance by approximately 5%) or select the next larger frame.
  4. Confirm Self-Locking Requirement: If load holding without power is required (hoist, gate, valve), specify a ratio of 20:1 or above. For ratios 10:1 and 15:1, a separate backstop or brake must be added for gravity-loaded applications — consult AS 4024 for guarding requirements.
  5. Check Direct Interchange Dimensions: If replacing an existing SEW WA, Motovario TA, or Rossi MW unit, provide the existing nameplate data to Ever-Power’s team for a confirmed dimensional interchange check before ordering. Mounting bolt pattern, output shaft diameter, shaft protrusion, and keyway dimensions are the key interchange parameters.

Accessories We Also Supply: IEC motor adaptor flanges (B5/B14), jaw couplings and hubs, output sprockets (pilot bore and finished bore), foot-mount shim packs for alignment, replacement oil seals (NBR and Viton), and replacement worm wheel assemblies. Contact our team at Contact Us for bundled pricing.

WPA Worm Gear Reducer Applications Across Australian Industry

The WPA is the default drive selection for a broad range of slow-speed, right-angle torque transmission applications. The following deployment scenarios represent the highest-volume WPA applications across Australia:

Sector & Location Application Typical WPA Size & Ratio
Food & Beverage (Sydney, Melbourne) Bottling conveyors, mixer drives, oven chain drives Size 63–100, ratio 20:1–40:1
Grain Handling (QLD, NSW, VIC) Grain auger head drives, grain conveyor tail shafts Size 80–135, ratio 20:1–30:1
Water Treatment (Perth, Adelaide) Sludge rake drives, filter-press drives Size 100–155, ratio 40:1–60:1
Pharmaceutical (Sydney, Melbourne) Tablet press feed drives, conveyor positioning actuators Size 40–60, ratio 40:1–60:1
Agricultural Machinery (SA, WA, QLD) Irrigation pivot drives, seeder metering drives Size 70–100, ratio 30:1–60:1
WPA worm gear reducer installed on Australian conveyor mixer and food processing machinery

WPA Maintenance Schedule — Keeping Your Worm Reducer Running Efficiently

Correct lubrication and timely inspection are the primary factors in achieving the WPA’s 20,000-hour design life. The following schedule applies to standard industrial conditions (ambient 20–35 °C, 8–16 hours/day operation):

Interval Task Notes
First 200 hours Drain & refill oil Run-in oil contains fine metallic particles — discard and replace with fresh ISO VG 220
Every 2,500 hours Oil change (mineral) Extend to 5,000 hours if synthetic PAO/PAG oil is used
Every 2,500 hours Oil seal inspection Replace on any visible seepage; upgrade to Viton seals if ambient exceeds 40 °C
Every 5,000 hours Bearing vibration check Replace bearings if housing RMS vibration exceeds 4.5 mm/s at rated speed
Annually Fastener torque check Re-torque foot-mount anchor bolts and motor flange fasteners to DIN 912 specification

What Australian Customers Say About the WPA Series

★★★★★

“We maintain over 40 WPA 90 units across our Melbourne bottling plant. The Ever-Power units are direct replacements for the SEW WA90s we ran for years — identical bolt patterns, same shaft dimensions, zero modifications. We’re saving about 30% per unit and the quality is equivalent. Re-ordering quarterly now.”

— Frank B., Maintenance Manager, Melbourne VIC

★★★★★

“Specified WPA 63 at 40:1 for our Brisbane bakery oven chain drives. 18 months with no issues. The units in the hot section near the ovens run warm but the oil seals have held perfectly — we use synthetic ISO VG 220 on those units which has helped. Great product for a tough environment.”

— Helen M., Plant Engineer, Brisbane QLD

★★★★☆

“Using WPA 50 units on small automation actuators in our Sydney pharmaceutical plant with servo motors at 60:1. They work precisely for our positioning requirements. One unit needed a re-torque of the motor flange bolts at the 3-month check — likely our installation. Overall very satisfied.”

— James O., Automation Engineer, Sydney NSW

★★★★★

“We distribute WPA units to irrigation dealers across SA and WA. Farmers appreciate the simple foot-mount — easy to install on a concrete base without specialist equipment. Delivery from Condell Park in under a week. Ever-Power is now our standard gearbox supplier for all WP-family replacements.”

— Colin T., Equipment Distributor, Adelaide SA

Why Choose Ever-Power for WPA Worm Gear Reducers in Australia?

Ever-Power Worm Gear Reducer Co., Ltd. (Australia), located at 27 Harley Crescent, Condell Park NSW 2200, maintains stock of WPA series units across all nine frame sizes and the most common ratios for fast 5–10 business day dispatch. Our engineering team provides free pre-purchase selection support and confirmed interchange checks against existing installed units — saving Australian maintenance managers the time and risk of ordering the wrong replacement. Learn more about our capabilities on our About Us page. Extended technical documentation is available at worm-gearbox.top.

  • ISO 9001:2015 certified supply chain with documented material traceability from raw material to finished unit
  • Australian Standards compliance: Product referenced against AS/NZS mechanical drive standards; documentation available for OHS and asset management records
  • Direct interchange verified against SEW-Eurodrive WA, Motovario TA/TR, and Rossi MW foot-mount series at common frame sizes
  • Volume pricing: Discounts available for orders of 10+ units — contact us for a project pricing schedule
  • Customisation: Non-standard shaft diameters, extended shaft lengths, Viton seal upgrades, IP65 sealing, and OEM labelling available with 2–3 week lead time

Frequently Asked Questions — WPA Series Worm Gear Reducer

1. Is the WPA a direct bolt-in replacement for SEW-Eurodrive WA series reducers?+
For the most common frame sizes (50, 60, 70, 80, 100, 120, 135), the WPA is dimensionally interchangeable with SEW WA units at the same centre distance — mounting bolt pattern, output shaft diameter, shaft protrusion length, and keyway dimensions all follow the same IEC/AGMA dimensional standards. Before ordering as a replacement, provide the existing unit’s nameplate data (centre distance, ratio, shaft diameter) to Ever-Power’s engineering team for a confirmed interchange check. Minor dimensional differences can exist at the smallest (40) and largest (155) frame sizes depending on the manufacturing era of the installed unit.
2. What worm wheel life can I expect from a WPA 90 at 30:1 in continuous 8-hour operation?+
Under 8-hour continuous duty at 70% of rated output torque, with ISO VG 220 mineral oil changed at 2,500-hour intervals, the tin-bronze worm wheel in a WPA 90 at 30:1 will typically achieve 15,000–25,000 operating hours before requiring replacement. Increasing load to 90% of rated torque approximately halves this expectation due to the exponential relationship between contact stress and surface fatigue life in bronze gear materials. Using synthetic ISO VG 220 oil extends expected life by approximately 20% compared with mineral oil. In 24/7 continuous heavy duty (mining, chemical plant), inspect the worm wheel at every 5,000 hours.
3. Can the WPA be used with a VFD (variable frequency drive) motor?+
Yes. The WPA gearbox is not affected by VFD operation — it sees only the mechanical input from the motor shaft regardless of how the motor is controlled. The caution for VFD applications applies to the motor, not the gearbox: at frequencies below 30 Hz (below ~900 rpm for a 4-pole motor), a standard TEFC motor’s cooling fan effectiveness decreases. For sustained operation below 30 Hz at significant load, specify a motor with a separately-powered forced cooling fan. There is no speed-dependent efficiency penalty in the WPA gearbox itself within the normal 300–1,500 rpm input speed range.
4. What are the signs that a WPA worm wheel needs replacement?+
Five indicators: (1) Output shaft speed becomes irregular — tooth wear producing variable effective ratio. (2) Bronze chips or particles visible in drained oil at oil change. (3) Audible increase in cyclic noise at output frequency — indicates tooth profile deviation. (4) Oil temperature increase above normal operating temperature by more than 10 °C — increased friction from worn contact area. (5) Output shaft backlash increase exceeding 2° when input is stationary. Replace the worm wheel when two or more of these indicators are present simultaneously. Replace worm shaft and wheel as a matched set whenever replacing the bronze wheel — installing a new wheel on a worn worm shaft accelerates re-wear significantly.
5. What is the difference between WPA and WPS, and when should I choose each?+
WPA covers sizes 40–155 and is the standard compact foot-mount unit for light-to-medium duty (up to approximately 7.5 kW, 900 N·m). WPS extends the range to size 250 and offers a larger output shaft section at each frame size — delivering approximately 30–40% higher overhung load capacity at the same frame, and significantly higher output torques at the larger sizes. Choose WPA when your application falls within the WPA power and torque range and overhung load is moderate. Choose WPS when: the application requires sizes above 155; the output shaft carries a heavy sprocket or pulley that would exceed the WPA’s overhung load rating; or when the application is classified as heavy-duty (24/7, high shock, or sustained near-rated-torque operation).
6. What is the recommended lubricant for WPA units operating in Australian food processing environments?+
For food processing and beverage environments where incidental contact with food product is possible, specify NSF H1-registered food-grade synthetic gear oil (PAG or white mineral oil base, ISO VG 220 equivalent). This lubricant is available as a factory pre-fill option from Ever-Power — specify “food-grade lubricant pre-fill” at order. NSF H1 food-grade synthetic oil also extends the oil-change interval to approximately 5,000 hours versus 2,500 hours for standard mineral oil, due to better oxidative stability. For washdown environments, also specify Viton (FKM) oil seals and IP65 sealing to prevent water ingress during CIP cleaning cycles common in Australian food and dairy facilities.

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