13 Frame Sizes for Heavy Industrial Applications
Each card links to the full specification page with power/torque tables, dimensional drawings, radial load data, and available configuration variants.
WPA 040
40mm CD | 4kg
26 Nm max
WPA 050
50mm CD | 7kg
43 Nm max
WPA 060
60mm CD | 10kg
75 Nm max
WPA 070
70mm CD | 15kg
113 Nm max
WPA 080
80mm CD | 20kg
163 Nm max
WPA 100
100mm CD | 35kg
291 Nm max
WPA 120
120mm CD | 60kg
413 Nm max
WPA 135
135mm CD | 80kg
707 Nm max
WPA 147
147mm CD | 98kg
848 Nm max
WPA 155
155mm CD | 110kg
848 Nm max
WPA 175
175mm CD | 150kg
1221 Nm max
WPA 200
200mm CD | 215kg
1782 Nm max
WPA 250
250mm CD | 360kg
2745 Nm max
WPA Series At-a-Glance
| Model | CD (mm) | Ratios | Max Torque (Nm) | Power (kW) | Output LS/S (mm) | Weight (kg) | Specs |
|---|---|---|---|---|---|---|---|
| WPA 040 | 40 | 5:1-60:1 | 26 | 0.12-0.48 | 28/14 | 4 | View |
| WPA 050 | 50 | 5:1-60:1 | 43 | 0.20-0.80 | 40/17 | 7 | View |
| WPA 060 | 60 | 5:1-60:1 | 75 | 0.32-1.25 | 50/22 | 10 | View |
| WPA 070 | 70 | 5:1-60:1 | 113 | 0.52-1.95 | 60/28 | 15 | View |
| WPA 080 | 80 | 5:1-60:1 | 163 | 0.75-2.65 | 65/32 | 20 | View |
| WPA 100 | 100 | 5:1-60:1 | 291 | 1.00-4.45 | 75/38 | 35 | View |
| WPA 120 | 120 | 5:1-60:1 | 413 | 1.50-6.15 | 85/45 | 60 | View |
| WPA 135 | 135 | 5:1-60:1 | 707 | 2.30-11.25 | 95/55 | 80 | View |
| WPA 147 | 147 | 5:1-60:1 | 848 | 3.00-14.50 | 95/55 | 98 | View |
| WPA 155 | 155 | 5:1-60:1 | 848 | 3.00-14.50 | 110/60 | 110 | View |
| WPA 175 | 175 | 5:1-60:1 | 1221 | 4.07-21.50 | 110/65 | 150 | View |
| WPA 200 | 200 | 5:1-60:1 | 1782 | 5.58-22.60 | 125/70 | 215 | View |
| WPA 250 | 250 | 5:1-60:1 | 2745 | 8.62-33.20 | 155/90 | 360 | View |
Max torque is the highest output torque achievable across all ratios at 1,500 RPM input. Actual continuous-duty torque depends on ratio, duty cycle, ambient temperature, and service factor. Refer to individual model pages for complete power/torque tables.
What Makes the WPA Series Different from EPNMRV
The following specifications apply across all 13 WPA sizes. Individual model pages do not repeat this information.
FG260 Cast Iron Housing
All WPA housings are cast from FG260 grey cast iron (equivalent to Grade 260 per AS 1831). FG260 provides a tensile strength of 260 MPa — approximately 2.5x higher than ADC12 aluminium. The superior vibration damping characteristics of cast iron reduce transmitted noise and protect bearings in high-vibration environments such as mining conveyors and crushing equipment. CNC-bored bearing seats ensure coaxiality within 0.02 mm.
Solid Shaft Input (Standard)
Unlike the EPNMRV series which uses hollow IEC-flanged input, the WPA uses a solid input shaft with keyway as standard. This makes the WPA suited for belt drives (V-belt, timing belt), chain drives, and direct coupling via flexible couplings — the dominant input configurations in Australian mining and heavy manufacturing. Input shaft diameter ranges from 12 mm (size 40) to 80 mm (size 250).
5 Shaft Direction Options
Every WPA size is available in five shaft direction configurations: A (input below/output horizontal), S (input above/output horizontal), O (output up), X (output down), Z (vertical). This eliminates the need for custom brackets or adapters when the driven machine requires a non-standard output orientation.
P, D, and K Configuration Variants
P (whole housing) = standard one-piece cast iron box with solid input shaft. D (split housing) = two-piece housing with integrated IEC motor flange adapter for direct motor mounting. K (hollow output) = hollow output shaft for direct shaft-mounted installation on the driven machine, eliminating coupling and baseplate. All combinations are available: WPDA, WPDS, WPKA, WPDKA, etc.
Efficiency & Self-Locking
Worm gear efficiency varies by ratio: 76-90% at 10:1, 74-84% at 20:1, 68-70% at 25:1, 65-75% at 30:1, 62-72% at 40:1, 60-70% at 50:1, 60-70% at 60:1. Self-locking is reliably achieved at ratios of 30:1 and above. Temperature correction factor a1: 1.0 for 10-40 degrees C, 1.6 for 41-50 degrees C ambient.
Lubrication Specification
Fill with N220-N320 mineral or synthetic gear oil for ambient temperatures 30-40 degrees C, or N320-N460 for 40-65 degrees C. First oil change after 100 hours of operation, then every 2,500 hours. Compatible oils: Shell Omala 220/320, Mobil DTE Oil BB/600W, Esso Spartan EP220/320. Do not use sulphur-phosphorus EP additives designed for steel-on-steel gears.
Selection Method & Application Data
Expand each section for detailed selection guidance applicable to all WPA/WPS sizes.
Step 1: Calculate Required Output Torque
Determine the theoretical output torque T1 based on your driven load.
Step 2: Apply Correction Factors
Corrected torque T = T1 x a1 x a2, where a1 = ambient temperature factor (1.0 for 10-40 degrees C, 1.6 for 41-50 degrees C) and a2 = duty cycle factor (0.8 for smooth/under 2h daily, 1.0 for smooth/2-10h, 1.2 for smooth/10-24h, up to 1.75 for heavy shock/10-24h).
Step 3: Calculate Input Power
P = (T x n2) / (9550 x efficiency), where n2 = output speed in RPM, and efficiency is from the ratio-efficiency table (0.60-0.90 depending on ratio).
Step 4: Match to Catalogue
Find the WPA size where both the input power and output torque meet or exceed your calculated values. Both conditions must be satisfied simultaneously.
Overheating
Causes: misalignment between motor and gearbox, overloading, excessive seal friction, incorrect oil level, contaminated oil. Solutions: realign shafts, reduce load, lubricate seal lip, adjust oil to sight glass level, replace oil.
Vibration
Causes: loose mounting bolts, worn worm gear set, worn bearings, misalignment. Solutions: tighten bolts to specified torque, replace gear set, replace bearings, realign.
Abnormal Noise
Causes: bearing damage, poor worm-wheel mesh, insufficient lubricant, foreign objects in housing. Solutions: replace bearings, re-shim worm wheel, top up lubricant, drain and flush housing.
Oil Leakage
Causes: worn seals, over-filled oil, loose drain plug, damaged sight glass. Solutions: replace seals, adjust oil level, apply thread sealant and tighten, replace sight glass.
Rapid Tooth Wear
Causes: overloading, incorrect lubricant, insufficient lubricant, overheating, failure to change oil at scheduled intervals. Solutions: reduce load or upsize gearbox, use correct worm gear oil (not steel-on-steel EP), maintain oil level and change schedule.