# Hydraulic Formulas and Fundamentals

## Fundamental Hydraulic Control Principles

### Things You Will Learn

Learn the fundamental parameters and formulas that define hydraulic equipment. This section will explain some of the key calculations that control how each system will perform.

### HF01 - Basic Theories and Formulas

Learn the basic theories and formulas that govern hydraulic equipment.

• How power is transmitted through fluid.
• Energy conservations.
• Thermal expansion
• Dimensional analysis

### HF02 - Pressure and Force Formulas

Learn the basic formulas that govern hydraulic equipment and experiment with formula values in the visual calculators.

• What creates hydraulic pressure.
• Formulas governing hydraulic force and pressure.

### HF03 - Flow and Pressure Drop Formulas

Learn the basic formulas that govern hydraulic equipment and experiment with formula values in the visual calculators.

• What controls hydraulic flow
• Formulas governing hydraulic flow

### HF04 - Hydraulic Power and Torque Formulas

Learn the basic formulas that govern hydraulic equipment and experiment with formula values in the visual calculators.

• What generates and what uses the hydraulic power.
• Formulas governing hydraulic power and torque and efficiency.
• Where system losses and inefficiencies occur and why they should be kept to a minimum.

### HF05 - Hydraulic Valve Design Fundamentals

Examine a range of hydraulic valves to see how they work. We look inside each valves and explore the pressure balances that make them work. We show you how to experiment with our valve simulations to explore their function and better understand how they work. Once you have grasped these basic principles you should be able to recognise the same parameters in other valves. Valves include:

• Hydraulic check valve operation
• Pilot operated relief valve operation
• Pressure reducing valve operation
• Pilot to open logic valve operation
• Pilot to close logic valve operation with unbalanced and balanced spools

### HF06 - Hydraulic Motor Fundamentals

Examine how valves affect the input and output power consumption of a simple hydraulic pumps and motor circuit. We look different ways of controlling the motor loads and see the effects on power consumption. We show you how to experiment with our circuit simulations to explore its function and better understand how the components work. Investigations include:

• Open and closed centre valves.
• Pressure relief valve and pressure reducing valve.
• Flow control orifice and pressure compensated flow control valve.
• Fixed displacement and pressure compensated pumps.

### Relevant Sectors

This module will NOT cover or apply to any specific equipment or industry. It is intended to lay down the basic building blocks for hydraulic circuit design without giving enough detail to explain specific mobile or industrial applications.

### Target Audience

People who want to learn how to maintain or design hydraulically driven equipment.

### Previous knowledge required

Students must appreciate where hydraulics is used and have a basic understanding of the components used and design of a simple hydraulic circuit.