Hydraulics Flashcards
Define a fluid
-A substance that will take the shape of its container
-Can be a liquid or gas
Pressure Formula
Pressure = Force/Area
What are the Advantages of Hydraulics compared to Electrics?
There are 8 advantages
-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 the size of equivalent electric motor
What are the Disadvantages of Hydraulics compared to Electrics?
There are 4 disadvantages
-Fire risk with mineral oil systems
-Noise
-Risk of Contamination
-Less Efficient (85-95%)
What is Denso Tape used for?
It is used to cover hydraulic fittings on the upper deck
What are the the hazards associated with Denso Tape?
It is highly flammable and gives off toxic fumes when burning
What are Fluorocarbon Elastomers used for?
Used to make ‘O Rings’
What hazards are associated with Fluorocarbon Elastomers?
When at exteme temperatures (300 Degrees Celcius), it can produce toxic gases such as Hydrogen Fluoride (HF)
What PPE is required when working with Fluorocarbon Elastomers?
There are 4 types of PPE required
-PVC Gauntlets
-PVC Coveralls
-Rubber Boots
-Full-Face Visor
What are the different types of Hydraulic Fluid?
-Petroleum Based (also known as Mineral)
-Synthetic Based
What are the different oils in use by the RN?
-OX30
-OX40
-OM33
-Rust Veto
What does O, X, M stand for when referring to oil and what does the number represent?
-O: Stands for Oil
-X: Stands for Synthetic
-M: Stands for Mineral
-Number: Represents Viscosity (Lower is Thinner)
Describe OX30
-Red
-Synthetic oil used in hydraulic machinery on HM Submarines
Describe OX40
-Green
-Synthetic oil used on hydraulic machinery on T23s, T45s and all future projects
Describe OM33
-Yellow/Orange
-General-Purpose petroleum based oil used on hydraulic machinery on T22s, T42s and CVS
Describe Rust Veto
-Used during upkeep periods when hydraulic oil has been removed from a system
-Used as a substitute to hydraulic fluid to prevent corrosion
What are the requirements for a Hyrdraulic Fluid?
There are 6 requirements
-Transmission of Power (Main Requirement)
-Fluid must easily flow through lines
-Must be incompressible
-Lubrication
-Sealing Properties
-Cooling
What are the most common causes of contamination in Hydraulic Oil?
There are 5 common causes
-Airbourne particles and moisture
-Construction Dirt
-Dirt in new fluid
-Dirt produced by wearing in new system
-Dirt from human sources
What are the methods of reducing contamination?
There are 7 methods
-Good system design
-Filtration and filter management
-Operation of filter and clogging indicators
-Good working practices
-Use of a guardian filter pack
-Caps should be fitted to open pipework
-Clean working area
What are the different types of Positive Displacement Pump?
There are 6 types
-Internal Gearwheel Pump
-External Gearwheel Pump
-Vane Type
-Lobe Type
-Radial Piston Type
-Axial Piston Pump
Do we need Dynamic Displacement Pumps in a Hydraulic System?
No, Hydraulic Systems need high pressure pumps
What are Axial Piston Pumps used on?
-Stabiliser Systems
-CPP Systems
-Steering Systems
What is the purpose of an Actuator?
To convert Hydraulic Energy into Mechanical Motion
What are the different types of Actuators?
-Linear
-Rotary
What are the different types of Linear Actuators?
-Single
-Double Acting
What is an Accumulator?
A device in which potential energy is held under pressure
What are Accumulators used for?
Storing energy and smoothing out pulsations
