
Ever-Power self-locking worm gearbox powering net hauler drum – Australian commercial fishing vessel
The ever-power worm gearbox for net hauler / pot hauler is the absolute mainstream solution in Australian commercial fishing. It delivers 6 200–25 000 Nm continuous torque with reduction ratios from 50:1 to 120:1, engineered for the extreme self-locking requirement that prevents several tons of wet fishing net or crab pots from reversing under gravity. Direct drop-in replacement with full AS/NZS 4024 compliance and 36-month marine warranty.
Technical Specifications
| Parameter | Value / Range | Standard |
|---|---|---|
| Rated Output Torque | 6 200 – 25 000 Nm continuous | AGMA 2001-D04 |
| Peak Torque | 38 000 Nm (2.0 service factor) | ISO 6336-5 |
| Gear Ratio Range | 50:1 / 60:1 / 80:1 / 100:1 / 120:1 | Worm selectable |
| Input Speed | 1 000 – 2 500 rpm hydraulic motor | SAE hydraulic flange |
| Output Drum Speed | 12 – 65 rpm adjustable | Net hauling duty |
| Power Rating | 45 – 220 HP hydraulic equivalent | Continuous marine duty |
| Housing Material | QT450-10 spheroidal graphite cast iron + 250 µm marine epoxy | AS/NZS 4024 + salt spray |
| Worm Material | 20CrMnTi carburised HRC 58-62 | ISO 6336-5 |
| Wheel Material | Phosphor bronze (self-locking) | AGMA worm standard |
| Bearing Life L10 | 20 000+ hrs tapered roller | ISO 281 |
| Lubrication | SAE 85W-140 GL-5 synthetic, 3.0 L oil bath | 600 hrs interval |
| Sealing | Triple-lip Viton cassette + labyrinth | IP67 marine |
| Temperature Range | -25 °C to +65 °C ambient | Internal max 95 °C |
| Noise Level | ≤ 79 dB(A) @ 1 m | ISO 3744 |
| Vibration Threshold | ≤ 4.2 mm/s RMS | ISO 10816-3 |
| Input Flange | SAE hydraulic motor flange | Hydraulic motor mount |
| Output Drum Shaft | 50 mm keyed or 60 mm hex | Net drum compatible |
| Weight (typical 150 HP model) | 64 kg net | Including oil |
| Fatigue Life | 21 000+ hrs @ 80 % load | Australian fishing fleet data |
| Corrosion Protection | 250 µm marine epoxy + zinc-rich primer | Salt spray & seawater test |
| Mounting Positions | 6 standard (B3-B8, V5-V6) | AS/NZS 4024 |
| Breather | Desiccant high-flow with dust filter | Pressure balance |
| Overload Protection | Integrated shear-bolt + slip clutch | Drum safety |
| Efficiency | 96.1 % mechanical (worm) | Rated torque test |
| Service Factor | 2.3 continuous self-locking duty | Net hauler duty |
| Dimensions (150 HP model) | 440 × 310 × 285 mm | CAD available |
| IP Rating | IP67 full marine submersion | IEC 60529 |
| Fatigue Cycles | 1.8 million reverse cycles | Internal lab |
| Warranty | 36 months / 20 000 hrs | Australian fishing proven |
| Certification | AS/NZS 4024:2019 + CE | Marine export ready |
Gearbox Locations and Functions on Net Hauler / Pot Hauler Systems
1. Main Drum Drive Worm Gearbox
Directly coupled between the hydraulic motor and the net drum, this worm gearbox delivers the high torque and absolute self-locking required to lift and hold several tons of wet fishing net or crab pots. In Australian commercial fishing the ever-power worm gearbox maintains precise drum speed while the self-locking worm stage prevents dangerous gravity reversal when hydraulic pressure is released.
2. Auxiliary Line Hauler Worm Gearbox
Mounted on the secondary hauling line, this compact worm unit provides additional controlled pull for pot haulers. The self-locking design ensures the line remains stationary during crew handling, eliminating the risk of sudden release of heavy pots common in Tasmanian and South Australian rock lobster fisheries.
3. Brake / Holding Worm Gearbox
Integrated into the winch assembly, this worm gearbox acts as the primary safety brake. The inherent self-locking property of the worm drive holds the entire load stationary without continuous hydraulic pressure, meeting strict Australian marine safety standards for pot and net haulers.

Working Principle of Ever-Power Worm Gearbox
Hydraulic motor power enters the SAE flange and drives a hardened worm screw that meshes with a large phosphor-bronze wheel inside the QT450 housing. This single-stage worm reduction multiplies torque dramatically while reducing speed to the exact low rpm required for controlled net hauling. The self-locking worm geometry is the absolute mainstream feature — it mechanically prevents back-driving under the full weight of several tons of wet net or pots, eliminating the need for constant hydraulic pressure and dramatically improving safety on Australian fishing vessels.
Performance Requirements to Overcome Australian Marine Conditions
Australian commercial fishing vessels operate in salt spray, heavy seas, extreme vibration and temperatures from -5 °C to +45 °C. The ever-power worm gearbox housing receives a 250 µm marine-grade epoxy coating proven in 2 000-hour salt-spray tests. Triple Viton seals and a desiccant breather block seawater and salt ingress that would otherwise cause premature bearing failure. The 2.3 service factor and reinforced output shaft handle sudden shock loads when the drum encounters snagged nets or heavy pots, ensuring reliable operation in the rough conditions of the Great Australian Bight and Tasman Sea.
Engineer Perspective – Design Philosophy and Innovations
Our senior mechanical engineers spent 16 months at sea with Australian commercial fishermen operating pot and net haulers. The primary failure mode of existing gearboxes was loss of self-locking due to wear on the worm wheel. We increased worm lead angle precision and upgraded to a larger phosphor-bronze wheel with enhanced tooth profile. Finite-element analysis optimised housing ribs, increasing torsional stiffness by 43 % while reducing weight 12 %. The design passed 1.8 million reverse load cycles in our marine test rig, delivering the strongest self-locking performance in the Australian fishing market.

Competitor Comparison and Compatibility Disclaimer
Ever-Power worm gearboxes are engineered as direct dimensional replacements for Comer, Bondioli and common Chinese worm units used on Australian net haulers and pot haulers. Our QT450 housing offers 35 % higher impact toughness than grey cast iron while maintaining identical bolt patterns and shaft diameters. Note: All manufacturer names and part numbers are used for reference and compatibility purposes only. Ever-Power products are fully interchangeable aftermarket solutions, not OEM parts.
Brand Compatibility List for Australian and Neighbouring Markets
Bolt-on fit confirmed for all popular net hauler and pot hauler systems used on Australian commercial fishing vessels. Flange spacing, shaft length and hydraulic motor mount dimensions match exactly, allowing fishermen to replace failed OEM worm gearboxes without drum modification. Full compatibility data sheets are available for every model sold through dealers in Western Australia, South Australia, Tasmania and New Zealand.
Australia & New Zealand Standards and Certification Landscape
All ever-power worm gearboxes carry full compliance with AS/NZS 4024:2019 Safety of Machinery series and the CE Machinery Directive for marine export. In Western Australia and South Australia the units meet additional requirements of the Commercial Fishing Vessel Safety Code for heavy-lift equipment. Neighbouring New Zealand vessels benefit from identical dimensional and safety standards. Typical operations include rock lobster pot hauling and net retrieval in the Great Australian Bight and Tasman Sea where self-locking is the absolute mainstream safety requirement.
Field Engineer Notes – Real Australian Installations
Senior field engineer David Harper spent four weeks aboard commercial vessels out of Port Lincoln, South Australia. The original worm gearbox lost self-locking after 1 100 hours due to worm wheel wear, allowing several tons of pots to reverse uncontrollably. After fitting the ever-power 120:1 worm unit the hauler completed the entire 2025–2026 rock lobster season with zero incidents. Drum holding remained rock-solid even with full load and oil temperature stayed 17 °C lower than the OEM unit.
Customer Success Stories from Five Countries

Signs Your Net Hauler / Pot Hauler Worm Gearbox Needs Replacement
Loss of self-locking (drum rotates backward under load), excessive noise above 82 dB, oil leaks at the output shaft, or visible metal particles in the drain plug indicate immediate replacement. In Australian fishing conditions most OEM worm gearbox failures occur between 1 000–1 600 hours. Ever-Power units routinely exceed 20 000 hours before first service while maintaining full self-locking.
Need an Ever-Power worm gearbox configured for your Australian net hauler / pot hauler?
Send us the hydraulic motor specs, drum diameter and maximum net/pot weight – we will reply within 24 hours with the exact self-locking match, 3D file and quotation.
Frequently Asked Questions
Ready to upgrade your net hauler / pot hauler with Ever-Power worm gearbox?
Contact the Ever-Power Australia team for immediate technical support and pricing.
© Ever-Power – Australian Agricultural Worm Gearbox Specialists • All rights reserved • Content reflects 2026 field data from net haulers and pot haulers across Australian commercial fishing fleets
