RT-Flex - Intelligent engines

These engines are equipped with high pressure rails of fuel and oil (common rail) and electronic control.

The designed rails offer new options as far as the engine design and operation are concerned, among the others they:

1. Simplified mechanical subassemblies of the engine.
2. Introduced flexibility of injection and valves operation.
3. Increased movement dependability of the engine due to the use of the double engine safety system.
4. Gave higher efficiency in comparison to traditional engines.
5. Introduced many options of reducing exhaust gas emission.

In the engines of "flex" type the designers resigned from such generally used so far designing schemes like:

1. Fuel pumps of SULZER construction - one big pump for one cylinder.
2. Overload valves (forward - backward).
3. Distribution shaft.
4. Overload actuator.
5. Distribution shaft drive (three or four gear wheels of ~1500 mm diameter).

Rejecting the above subassemblies allowed to introduce innovative designing solutions, e.g.:

1. Injection pumps of Bosch type - for example for 7-cylinder engine there are just three small pumps generating fuel pressure for the rail.
2. The fuel rail - capable of keeping fuel pressure of ~1000 bar.
3. Injection control assembly - small hydraulic device enabling precise control of the injection parameters.
4. Oil rail - powered with two small piston pumps (for 7-cylinder engine), in which the pressure of ~200 bar is maintained.
5. The WECS - 9520 system was designed, which supervises correct operation of the whole engine. Each engine cylinder is equipped with individual computer and realises functions assigned just for this particular cylinder. The whole communication between computers is conducted through logical system CAN-Bus (one cable). Cooperation with ship steering system is conducted just through two CAN-Bas cables which greatly reduced number of the connection cords.

The engine electronically controlled offers possibilities not known so far in traditional designs. For the cylinder equipped with three injectors the system controls the amount and order of injectors operation, for example at the speed of 10 - 15 r.p.m. operates just one injector in the cylinder (changed for another one every tens of seconds). At low revolutions two injectors work (also changed every tens of seconds). At heavy loads, work all three injectors which can be precisely controlled, that is the start of the injection before GMP, amount of fuel supplied to the combustion chamber and pressure of fuel delivered, etc. can be controlled. There are plenty of possibilities, the system will always try to work at its optimum, which in case of huge engines means work with minimal fuel consumption.