Mechanical loss is the loss of input power caused by friction and mechanical resistance between internal pump components.
It represents the difference between:Mechanical input power, and Useful hydraulic power delivered
Higher mechanical loss = Lower overall pump efficiency.
Friction occurs in:
Gears & bushings
Pistons & cylinder bores
Vanes & cam rings
These resist motion and consume additional power.
Smooth surfaces & precision machining minimize this loss.
Mechanical resistance increases due to:
Bearing friction
Shaft misalignment
Unbalanced loads.
This leads to higher torque requirements and reduced mechanical efficiency.
Mechanical losses increase when:
Lubrication is insufficient
Oil viscosity is too high
Oil film cannot form properly
Result: higher drag, more heat, faster wear.
High mechanical loss causes:Increased energy consumption,Excessive heat generation,Reduced pump lifespan,Lower hydraulic performance.
Optimizing lubrication, alignment, and component quality significantly reduces mechanical loss.
