Hydraulic Training Course - Exercise 1
Experiment with different fixed displacement pump power unit designs
Exercise content and aims
Typical Applications - Small mobile and industrial power units
Topics covered - How to match the type of valve and pump to give you the most efficient and reliable systems.
Components - Fixed Displacement Pump with Open or Closed Centre Valve
Level - 
Novice
To start, run the 'Hydraulic Circuit Builder' simulation and training program
Load circuit: PU001 into Hydraulic Circuit Builder.
Topic covered: - Power Unit Designs
- Efficient power unit design
- Fixed displacement pump with closed centre valve
- Fixed displacement pump with open centre valve
Understand Basic Hydraulic Power Demands
Observe: Move your mouse over the fixed displacement gear pump. Observe the flow and pressure.
Question: What is creating the pressure level.
Question: Why is the actual pressure higher than the relief valve's set pressure.
Experiment: Operate the directional valve and watch how the pressure changes.
Question: What is creating the pump pressure when the cylinder is moving.
Test the effects of different directional valve centre conditions
Experiment: Select the best directional valve centre condition to ensure the minimum amount of heat is generated when the cylinder is not being moved.
Question: Which is the most appropriate spool for a fixed displacement pump
Experiment: Change the pump flow, valve size and the relief valve's pressure rise rate to match your system design. Compare how much power is being put into the fluid with the useful work you are getting out. Use the e4training power unit design calculator to find the temperature levels that will be seen in your power unit's reservoir.