Welcome to Tea with Didi

Nov 22, 2019


  • Flanagan Balling posted an update 4 months, 1 week ago

    Have you driven through a bad puddle of water just to have your miserable engine lock solid after ingesting a cylinder full? This is what’s called hydraulic lock and is also an expensive instance of hydraulic power which hydraulic oils convey.

    Within this commentary I will be emphasizing hydraulic fluids instead of brake fluids, that happen to be an incredibly specialized sub grouping.

    Functions and properties

    The purpose of hydraulic oils is always to convey power. Then again, there are other significant functions of present hydraulic fluids.

    The table below lists the principle functions of hydraulic oil and the properties with the fluid that shape its capability to perform that function:

    Hydraulic Performance properties

    • Low compressibility (high bulk modulus)

    • Quick air release

    • Low foaming tendency

    • Low volatility

    Thermal performance

    • Good thermal function and conductivity

    Sealing properties

    • Adequate viscosity and viscosity index

    • Shear stability


    • Satisfactory viscosity for film maintenance

    • Low temperature fluidity

    • Thermal and oxidative stability

    • Hydrolytic stability / water tolerance

    • Purity and filterability

    • Demulsibility

    • Wear reduction characteristics

    • Corrosion control

    Pump efficiency

    • Appropriate viscosity to curtail internal leakage

    • Superior viscosity index

    Special requirements

    • Fire resistance

    • Friction modifiers

    • Radiation resistance

    Environmental impact properties

    • Low toxicity when new or decomposed

    • Biodegradability


    Dating back ancient Egypt the mode for hydraulic fluid was water. It had been only within the 1920s that mineral oil has become used. This became as a result of oils inherent lubrication properties and gratification at temperatures across the boiling point of water. Today most hydraulic fluids derive from mineral oil base stocks and more recently synthetic alternatives.

    Current hydraulic oils can possess a wide range of chemical compounds, and also: mineral oils, butanol, esters (e.g. phthalates, like DEHP, and adipates), polyalkylene glycols (PAG), phosphate esters (e.g. tributylphosphate), silicones, alkylated aromatic hydrocarbons, polyalphaolefins (PAO) (e.g. polyisobutenes), corrosion inhibitors, etc.

    For environmentally hypersensitive applications, such as farm tractors and marine dredging (and then there will be the reaction of an oil spill from the ruptured oil line), biodegradable hydraulic oils determined by rapeseed (Canola) vegetable oil can be utilized (often combined with tailored synthetic esters). Typically these oils can be obtained as ISO 32, ISO 46, and ISO 68 specification oils

    Other base stocks can be used for specialty applications, for example for fire resistance and extreme temperature applications. Examples embrace: glycol, esters, organophosphate ester, polyalphaolefin, propylene glycol, and silicone oils (For Brake fluids).

    Aircraft hydraulic systems

    As aircraft performance improved, and so the force needed to activate mechanical flight controls increased, and hydraulic systems were introduced to ease pilot effort. Hydraulic power can also be accustomed to start the auxiliary power unit (APU) for self-starting the aircraft’s main engines. While several aircraft equipped with the M61 family of cannon, exploit hydraulic capability to drive the gun system, permitting reliable high rates of fireplace.

    To read more about

    dau thuy luc 68 go to our new internet page.

Stay Connected

Receive our newsletter and alerts:

Email *