EcoMaster ZWG series with fully automatic Allison 4750 provides fuel savings up to 40 liters per operating hour, an improvement of 60 percent
DUISBURG, Germany – With its EcoMaster ZWG series, WOMA GmbH became the first company to offer high-pressure water cleaners with fully automatic transmissions. Equipped with the Allison 4750, the water jet technology provides advantages in terms of performance, fuel economy, water consumption and ease of use.
"The strength of this product is the fully automatic transmission that has been integrated between the high-pressure pump and the diesel engine,"said Günter Toonen, vice president of project management for WOMA. "The Allison transmission controls the speed of the pump in a power range of 50 to 500 kW. So the amount of water required is dosed precisely, and that enables important water-saving."
High-pressure water cleaners with capacities up to 4,000 bar are the specialty of the Duisburg-based company WOMA, a subsidiary of the international Kärcher Group. They cut concrete and iron, help to clean bridges and building facades, or clean contaminated soils and tanks by means of a concentrated water jet.
For mobility, the EcoMaster ZWG can be mounted on a truck. Additionally, the combination of WOMA’s top-selling Z-Line pump and an Allison Automatic enables water pressure to reach up to 1,000 bar with a maximum nominal flow rate of 262 l/min.
In this application, six of the seven gears available on the Allison 4750 Oil Field Series™ transmission are used: five gear reductions and one overdrive. The gear selection is made electrically by a push button on the control cabinet. While the engine is running, the speed of the high-pressure pump can be adapted to the particular application and the local conditions, thus significantly reducing the fuel consumption.
"Depending on the selected gear, up to 40 liters of fuel per operating hour can be saved compared to machines without transmissions," said Toonen.
Available with the Volvo Penta TAD1672VE or TAD1643VE engine, the overdrive function of the Allison transmission in sixth gear consumes up to 10 percent less fuel at a lower engine speed than the same pump, at full power, without an automatic transmission. The speed reduction also results in less noise, and reduced wear of the pump, which makes it more durable and less expensive to maintain.
The Allison 4750 with a torque converter and Power Take-Off (PTO) provision is suitable for engines up to 665 hp (496 kWh) and a torque of 2,644 Nm. For the EcoMaster ZWG, the integrated PTO manages lubrication of the water pump to ensure smooth, continuous operation.
"With the flexibility of combinations, we can cover a complete range of models and offer a wide range of high-pressure applications for the industry," said Toonen.