Multiplication & variation of force Easy, accurate control One power source controls many operations High power / low weight ratio Low speed torque Provides constant force and torque Safe in hazardous environments Why Use Fluid Power ?
A system that transmits and controls energy through the use of fluid Liquid or Gas? Pneumatics - the media used is air Hydraulics - the media used is oil or water What is Fluid Power ?
Operation of system valves for air, water, or chemicals Operation of heavy or very hot doors Unloading of hoppers in building, steel making, mining and chemical industries Ramming and tamping in concrete and asphalt laying Lift heavy loads (i.e. forklifts and loaders) What can Fluid Power Do ?
Lifting and moving in slab molding machines Crop spraying Paint Spraying Holding and moving parts or assemblies in manufacturing What can Fluid Power Do ?
Jig (guides cutting tool) and Fixture (stationary work holding) clamping Forming operations of bending, drawing and flattening Bottling and filling machines Machine tool changing What can Fluid Power Do ?
Component and material conveyor transfer Robots Dentist drills Vacuum lifting for thin sheet materials Store Energy …and much..much..more What can Fluid Power Do ?
Basic Fluid Power Components Reservoir and Receiver Stores fluid before and after use Fluid Conductors Pipe, tube, or hose for flow between components Pump / Compressor Converts mechanical power to fluid power Valve Controls direction and amount of flow Actuators Converts fluid power to mechanical power
Fluid Power Principles Rate of Flow Determines actuator speed Measured in gallons per minute (gpm) Generated by a pump
Fluid Power Principles Flow Makes actuator operation possible To extend the cylinder, flow is directed into Port B Retracted cylinder
Fluid Power Principles Flow Makes actuator operation possible Flow is directed into Port B and cylinder is extended. To retract the cylinder, flow must be directed how?
Fluid Power Principles Flow Makes actuator operation possible The cylinder retracts when flow is directed into Port A. To retract the cylinder, flow must be directed how?
Fluid Power Principles With a Given Flow Rate Actuator volume affects actuator speed The less volume, the faster the actuator Example: Will the actuator illustrated below travel the same speed as it retracts and extends if a constant flow rate is maintained? Almost. The actuator will travel faster as it retracts. Less volume for fluid due to presence of the actuator shaft.
Fluid Power Principles Pressure The resistance to flow Pumps produce flow, not pressure - If you restrict the flow from the pump, pressure will result. All points of resistance in series contribute to total system pressure - i.e. long runs of pipe, tees, valves, elbows, etc.
Fluid Power Principles Heat Law of conservation of energy states that energy can neither be created nor destroyed, although it can change forms. Energy not transferred to work takes the form of heat energy. Nerd note: Engineers calculate the wasted horsepower in the system by measuring the cooling requirements.
Fluid Power Principles Torque The generated work of a hydraulic or pneumatic motor Motor rpm at a given torque specifies energy usage or horsepower requirement
Fluid Power Principles Horsepower Term gives relative meaning for measuring power Unit measurement of energy Hydraulic horsepower is expressed as: HP = Flow (gpm) x Pressure (psi) 1714 (a conversion constant)
Fluid Power Principles Calculate the horsepower needed in the system below to lift a 10,000lb force in 2 s.
More Boring Fluid Power Crap NOTE 1 : Place all boring slides after this one NOTE 2: This slide not for student viewing
Fluid Power Schematics Schematics Line drawing made up of a series of symbols and connections that represent the actual components in a hydraulic system
Fluid Power Schematics Symbols Critical for technical communication Not language-dependent Emphasize function and methods of operation Basic Symbols
Resources National Fluid Power Association. (2008). What is fluid power. Retrieved February 15, 2008, from http://www.nfpa.com/OurIndustry/OurInd_Abou tFP_WhatIsFluidPower.asp National Fluid Power Association. (2000). Fluid Power Training. National Fluid Power Association & Fluid Power Distributors Association. (n.d.). Fluid power: The active partner in motion control technology. [Brochure]. Milwaukee, WI: Author