Engine Performance Curves 2

[gcomyn]

I'm looking at a series of diesel engine performance curves for a Cat 3516C marine propulsion engine. There are several curves shown. What is meant by Zone 1 Curve 1, Zone 2 Curve 2, Zone 3 Curve 3, Max Limit Curve 4, and Prop Demand Curve P?

 

[reidh]

Can you provide a link to the aforementioned curves?

-Reidh

 

[gcomyn]

I've tried to upload the file, but it isn't working. The file is probably too big. I'll try again later.

 

[catserveng]

Curve P indicates the horsepower that is demanded of the engine by a fixed pitch propellor installed on a displacement hull, operating at various speeds. The curve depicts a series of steady state operating points at various engine speeds.

Curves 1-4 are located above curve P and are indicators of how much horsepower is available above the prop demand curve for various lengths of operating time.

Curve 1 is usually the continuous operating curve, the other curves correspond to ratings other than continuous.

Your local CAT Marine Sales rep should be able to provide you more information. Ask for CAT publication LEKM0831, Marine Engine and Boat Performance, or LEBV4830, Marine Analyst Service Handbook for further reference.