hydraulics Flashcards
what is the definition of fluid
- It is a substance that will readily take the shape of its container
- It is capable of transmitting power
- It can be a liquid or gas
what are the hydraulic multiplications
A = Area – area of the piston face
F = Force – force acting on a piston / force transmitted by a piston
P = Pressure – pressure exerted on the system fluid
what are 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
what are the disadvantages of hydraulics
- Fire risk with mineral oil systems
- Noise
- Risk of contamination
- Less efficient (85-95%)
why should denso steel working masic be kept in the flammable store?
because it gives off toxic gasses when ignited so it should only be kept on the upper deck.
why are pipework sealing joins a hazard
the carry Orings that are made of flurocarbon elastomers which when burned at high temperatures flurocarbon elastomers will give off toxic gasses such as hydrogen fluoride.
what is the antidote for coming in contact with hydrogen fluoride?
calcium gluconate gel
what is the ppe for working with flurocarbon elastomers
- PVC gauntlets
- Rubber boots
- PVC coveralls
- Full-face visor
what are the two types of hydraulic fluid
Petroleum based. Petroleum based oils are general purpose (inexpensive) mineral oils.
Synthetic based. Synthetic oils are man-made, for specific purposes.
what are the 3 types of oil
- OX30. This is RED in colour. A synthetic oil used in hydraulic systems on-board submarines
- OM33. This is Yellow / Orange in colour. A general-purpose petroleum based hydraulic oil used in all the hydraulic systems on T42’s, T22’s & CVS
- OX40. This is GREEN in colour. A synthetic oil used in all hydraulic systems on T23’s, T45’s and all future projects
what is rust veto
Is used during upkeep periods where hydraulic oil has been removed from a system, Rust Veto is put in as a substitute for the hydraulic fluid to prevent corrosion
what are the requirements of hydraulic fluids
- The main requirement of a hydraulic fluid is for the transmission of power
- The fluid must flow easily through lines
- It must be as incompressible
- Lubrication is another important requirement
- Sealing Properties
- Cooling is another role for hydraulic fluid.
what are the common causes of contamination in oil
- Airborne particles and moisture
- Construction dirt
- Dirt in new fluid
- Dirt produced by wearing in new system
- Dirt from human sources
what does Demulsibility
the ability of fluid to separate out of water
what are 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 pack
- Caps should be fitted to open pipework
- Clean working area
