Often it is important in an illustration to tell a story in the most simple way, by means of a cut away, cross section or an exploded view. Keeping the focal point on what is really important and minimising the unnecessary information.
Fielders Mobile Mill
Sectional cutaway of Sand Blaster helmet
Pavlov's Dog experiment
Land form cross section
Home Water Supply
Braemar Gas Ducting
Arm movement
Car Battery Cutaway