From 2014 onward, a new engine family will extend the Hatz product range: The H-series. Beginning with the water-cooled 4-cylinder 4H50TIC model, with the new generation Hatz is focusing on common rail technology, turbochargers and external exhaust gas return.
A pioneering downsizing approach has been pursued in the development of the 4H50TIC. The prime development objectives were the reduction of size and weight with simultaneously higher power and good exhaust gas values. The outcome is a turbocharged 2-liter engine that reaches a maximum power output of 55 kW with a weight of 173 kg, setting the benchmark in its performance class. The engine meets the strict exhaust emission limits of EU 97/68 Stage IIIB and EPA Tier 4 final without particle filters.
All mechanical components have been designed and developed with a conservatively innovative approach. The 4H50TIC is equipped with two valves per cylinder, achieving high efficiency, mechanical robustness and functional simplicity. This, in turn, is expressed in the familiar long service life, something that is also supported through the exclusive use of premium products in all important components.
One of the key factors for the high performance compactness of the 4H50TIC is the common rail system. Hatz decided upon the off-highway CRS from Bosch with 1800 bar. It works with three precisely dosed injections per working cycle: a pre-injection, main injection and post injection. In combination with the other ideally matched Bosch system components – high pressure pump, injection controller and off-highway injectors – a perfect balance is struck between dynamics, quiet combustion noise, low levels of hazardous substances and economy.
In terms of fuel efficiency, the newly developed engine with a specific consumption of just 210 g/kWh sets new standards at the maximum efficiency point. The innovation here is that consumption values are achieved which lie close to the optimum operating point across a wide load and speed range. This has never been achieved so far and makes the 4H50TIC the most efficient engine in the class of 37-56 kW.
The exhaust gas return system was further developed by Hatz engineers to have a positive effect on the exhaust gas values. A pre-cooling section for the exhaust gas return significantly reduces the exhaust gas temperature before the AGR valve, protecting it against damage and sooting. An optimized AGR mixing nozzle is also used, which evenly distributes the returned exhaust gases together with the fresh combustion air to all four cylinders. Together with the common rail system, this results in outstanding exhaust gas quality which ensures that the 4H50TIC is only equipped with one oxidation catalytic converter and there is no need to additionally attach a particle filter. And the engine still falls significantly below the exhaust gas values of EU 97/68 and EPA.
With a maintenance interval of 500 hours, the engine can score highly in terms of customer friendliness and reliability. The extended intervals are attributed to hydraulic valve play compensation and large sized filters. The engine also has a sensor-controlled engine protection system which switches off the engine in an emergency to prevent major damage. The robust construction and careful selection of all components ensure that the engine meets the most demanding applications.