Hydraulics Flashcards
What are the 3 statements that define a fluid?
- A substance that will take the shape of it’s container.
- A substance capable of transmitting power
- It can be a liquid or a gas
What does A (Area) relate to in hydraulics?
Area of the piston face
What does F (Force) relate to in hydraulics?
Force acting on a piston / transmitted by a piston
What does P (Pressure) relate to in hydraulics?
Pressure exerted on the system fluid
What acronym needs to be remembered in order to calculate Force, area or pressure?
FAP
State the advantages of hydraulics
- It is reliable
- Simple and easy to understand
- Infinite speed range
- Easily reversed
- Ability to withstand overload
- No spark risks
- High torque at low speeds
- 1/12 size of equivalent electric motor
State the disadvantages of hydraulics
- Fire risk with mineral oil systems
- Noise
- Risk of contamination
- Less efficient
What PPE should be worn when working with fluorocarbon elastomers?
- PVC gauntlets
- Rubber boots
- PVC coveralls
- Full-face visor
What toxic gas is given off when fluorocarbon elastomer O rings reach extreme temperatures?
Hydrogen fluoride
What are the 2 types of hydraulic fluid?
- Petroleum based
2. Synthetic based
When are synthetic based hydraulic oils used for?
Specific purposes.
What are the requirements of a hydraulic fluid?
- Able to transmit power
- The fluid must flow easily through lines
- It must be incompressible
- Lubrication
- Sealing properties
- Cooling
What are the most common causes of contamination in hydraulic oil?
- Airborne particles and moisture
- Construction dirt
- Dirt in new fluid
- Dirt produced by wearing in a new system
- Dirt from human sources
State the methods of reducing contamination
- Good system design
- Filtration and filter maintenance
- Operation of filter and clogging indicators
- Good working practices
- Use of guardian filter packs
- Caps should be fitted to open pipework
- Clean working area
State the types of hydraulic pumps
- Internal gearwheel type
- External gearwheel type
- Vane type
- Lobe type
- Radial piston type
- Axial piston pump
What systems are axial pumps used on?
- CPP systems
- Stabiliser systems
- Steering systems
What are the 2 types of Actuator?
Linear and rotary
What does an actuator do?
Converts hydraulic energy into mechanical motion.
What does an accumulator do?
An accumulator holds energy under pressure. This is then released to smooth out pulsations.
