Fluid Power Basics
Practical knowledge about hydraulic and pneumatic components and systems
Written by: Bud Trinkel, Certified Fluid Power Engineer
Edited by Mary Gannon and Richard Schneider, Hydraulics & Pneumatics magazine.
Table of Contents
Preface and Forward
Answers to Ebook 1 Quizes
Chapter 1: Fluid Power Basics -- Sponsored by Clippard Instrument Laboratory, Inc.
What is fluid power? • Who uses fluid power? • Who is responsible for fluid power? • What are the advantages and disadvantages of fluid power? • Which should be used: hydraulics or pneumatics? • Basic laws governing fluid power • Pascal's law • Work and power • Compressibility of fluids • Boyle's law • Charles' law • Static head pressure • Vacuum • Quiz
Chapter 2: Hydraulic Fluids -- Sponsored by Hercules
What hydraulic fluids do: transmit energy, lubricate, seal • How are hydraulic fluids specified? • Viscosity • Viscosity index • Pour point • Common fluid additives • Lubricity adders • Viscosity modifiers • Oxidation resistance • Wear inhibitors • Anti-foam inhibitors • Rust inhibitors • Fluid temperature considerations • Fire resistant fluids • Water • High water content fluid • Water-in-oil emulsions • Water glycol • Synthetics • Handling new fluid • Storing hydraulic fluids • Quiz
Chapter 3: Plumbing -- Sponsored by Midland Metal Mfg.
Plumbing a fluid power system • Considerations when plumbing a plant air system • Pipe types and size • Standard pipe layouts • Grid piping system • Loop piping system • Unit distribution system • Typical air piping side view • Pneumatic machine plumbing • Considerations when plumbing a hydraulic system • Pipe types and sizes • Hose • General rules for sizing hydraulic lines • Pump inlet line • Return lines • Working pressure lines • Quiz
Chapter 4: ISO Symbols and Glossary -- Sponsored by Hydac
Part 1 : Part 2 : Part 3
Fluid power schematic symbols • Basic information • Reservoirs • Filters • Pumps • Flow meters • Relief and unloading valves • Directional control valves • Check valves • Spool valves • Proportional valves • Servovalves • Cartridge valves • Prefill valves • Flow-control valves • Sequence valves • Counterbalance valves • Cylinders • Rotary actuators • Pneumatic and hydraulic motors • Flow dividers • Accumulators • Accessory items • Measuring devices • Air Logic
Chapter 5: Basic Fluid Power Systems -- Sponsored by Hercules
Two types of fluid power circuits in this manual • Schematic drawing of a pneumatic circuit • Physical drawing of a pneumatic circuit • Typical pneumatic circuit • Why a schematic drawing • Parts of a typical pneumatic system • Air logic controls • Directional control valve • Limit valve • Air drills • Schematic drawing of a hydraulic circuit • Physical drawing of a hydraulic circuit • Typical hydraulic circuit • Parts of a typical hydraulic system • Directional control valve • Pressure control valves • Accumulators • Conventions used in this publication • Quiz
Chapter 6: Reservoirs, Heaters, and Coolers -- Sponsored by Hydac
Air receivers • Hydraulic reservoir types • Hydraulic reservoir function • Reservoir cooling formula • Tank heating types and formula • Air and water type fluid coolers • Quiz
Chapter 7: Air and Hydraulic Filters, Air Dryers and Lubricators -- Sponsored by MP Filtri
Air filters and lubricators • Compressed air dryers: deliquescent, refrigerant, and desiccant • Filter rating • Beta Ratio • Filter placement • Quiz
Chapter 8: Pumps and Accessories -- Sponsored by Metaris
Part 1 : Part 2
Pneumatic pumps • Air compressor installation • Hydraulic pumps • Non-positive displacement pumps • Positive displacement pumps • Gear, internal, external, gerotor • Screw • Vane, un-balanced, balanced • Circuits for fixed volume pumps • Variable-volume pumps: vane, piston, radial, wobble-plate, in-line or axial, bent-axis • Load sensing, horsepower, or torque limiting • Circuits for pressure-compensated pumps • Air bleed valves • Closed-loop bi-directional pumps • Bi-rotational pumps • Cavitation causes and damage • Pump mounting and alignment • Pump testing • Quiz
Chapter 9: Relief Valves and Unloading Valves -- Sponsored by Command Controls Corporation
Why a relief valve? • Relief valve terms • Direct acting relief valve • Pilot-operated relief valve • Remote controlled relief valve • Solenoid Operated relief valve • Proportional relief valve • Direct acting unloading valve • Pilot operated unloading valve • High-low pump circuit • Modular relief valve symbols • Quiz
Chapter 10: Directional Control Valves -- Sponsored by Pneumadyne, Inc.
Part 1 : Part 2 : Part 3 : Part 4 : Part 5
Check valves • Pilot-to-open and pilot-to-close check valves • Pilot-operated check valve circuits • Pre-fill valves • Pre-fill valve circuit • 2-Way, 3-Way, 4-Way, 5-Way valve flow functions and symbols • Valve types • Sliding plate, poppet, and spool types • Spool valve advantages and disadvantages • Hydraulic 4-Way spool valves • All ports open, all ports closed, float center, and tandem center • Solenoid pilot operated valves • Crossover conditions • NFPA and ISO Sub-plate layouts • Schematic bar manifold drawing example • Quiz
Chapter 11: Slip-In Cartridges (Logic Valves) -- Sponsored by Holmbury
What are slip-in cartridge valves? • Advantages of slip-in cartridge valves • 1:2 slip-in cartridge valves and how they are used • 1:1.1 slip-in cartridge valves and their uses • 1:1 slip-in cartridge valves and their function as pressure controls • Slip-in cartridge valves as a reducing valve • Quiz
Chapter 12: Infinitely Variable Directional Control Valves -- Sponsored by Linde Hydraulics
What are infinitely variable directional control valves? • Where are infinitely variable directional control valves used? • Proportional infinitely variable directional control valves • Servo infinitely variable directional control valves • Quiz
Chapter 13: Flow Controls and Flow Dividers -- Sponsored by Amisco
Fixed orifices • Needle valves • Non-compensated flow controls • Pressure-compensated flow controls • Proportional flow controls • Three port flow controls • Priority flow controls • Spool type flow dividers • Motor type flow dividers • Quiz
Chapter 14: Pressure Control Valves (Except Relief and Unloading Valves) -- Sponsored by Pressure Components Inc.
Sequence valves • Sequence valve circuit • Counter Balance Valves • Counterbalance valve circuits • Reducing valves • Reducing valve circuits • Reducing relieving valves • Reducing relieving valve circuits • Air line regulators • Quiz
Chapter 15: Fluid Power Actuators -- Sponsored by Sheffer Corporation
Part 1 : Part 2
Single-acting rams, push type and pull type • Telescoping cylinders single and double acting • Spring-return or spring-extend cylinders • Diaphragm actuators • Bellows actuators • Rotary actuators • Hydraulic motor • Quiz
Chapter 16: Accumulators -- Sponsored by Ogden Hydraulics
Non-separated, bladder, piston, and weight-loaded types • Accumulator applications by type • Accumulator dump and unloading valves • Common accumulator circuits • Quiz
Chapter 17: Air-Oil Systems & Intensifiers -- Sponsored by Interface Devices, Inc.
Air-oil tanks and circuits • Tandem cylinders and circuits • Air to hydraulic and hydraulic to hydraulic single stroke intensifiers • Air-to-air, air-to-hydraulic, and hydraulic-to-hydraulic reciprocating intensifiers • Quiz
Chapter 18: Miscellaneous Fluid Power Items -- Sponsored by Elettrotec
Electric motors, heat engines, non-electric motors • Shuttle valves • Quick exhaust valves • Quick-acting couplings • Pressure gauges • Temperature gauges • Rotating unions • Flow meters • Pressure switches • Shutoff valves • Mufflers • Machine members • Quiz
Chapter 19: Moving Part Air Logic Controls -- Sponsored by Crouzet North America
And • Or • Not • Yes • Flip-Flop • Memory • Differentiator • On-delay timer • Off-delay timer • Frequency generator • Pressure decay sensor • Sequencer • Sequence valve • Anti-tiedown • Counters • Air logic circuits • Quiz
Chapter 20: Brain Teasers -- Sponsored by Lynch Fluid Controls Inc.
Chapter 21: Practice Circuits -- Sponsored by Bosch Rexroth
Chapter 22: Useful Formulas
Fluid Power Basics, Copyright 2007 by Penton Media Inc. No part of this document may be used or reproduced in any manner without written permission except for brief quotations embodied in critical articles or reviews.
