Wärtsilä 32 Product Guide

Wärtsilä 32 - Product Guide
2. Operating Ranges
2.2.1 Mechanical propulsion
Figure 2.4 Maximum recommended load increase rates for variable speed engines
The propulsion control must include automatic limitation of the load increase rate. If the control system has
only one load increase ramp, then the ramp for a preheated engine should be used. In tug applications the
engines have usually reached normal operating temperature before the tug starts assisting. The “emergency”
curve is close to the maximum capability of the engine.
If minimum smoke during load increase is a major priority, slower loading rate than in the diagram can be
necessary below 50% load.
Large load reductions from high load should also be performed gradually. In normal operation the load
should not be reduced from 100% to 0% in less than 15 seconds. When absolutely necessary, the load
can be reduced as fast as the pitch setting system can react (overspeed due to windmilling must be considered
for high speed ships).
2.2.2 Diesel electric propulsion and auxiliary engines
Figure 2.5 Maximum recommended load increase rates for engines operating at nominal speed
Product Guide W32 - 1/2013 9