hydraulic technical library
Hydraulic troubleshooting, maintenance and repair tips, application formulas and guidelines, conversions and other technical data designed to help you solve your hydraulic problems.


High pressure fluid is present in operational hydraulic systems. Fluids under high pressure are dangerous and can cause serious injury or death. Do not make modifications, repairs or adjustments to any hydraulic system unless you are competent or working under competent supervision. If in doubt consult a qualified technician or engineer.


Hydraulic equipment maintenance - why it's so important

Hydraulic Cylinders
A popular myth about hydraulic cylinders - exploded!
Hydraulic cylinder failure caused by the diesel effect
Hydraulic ram leak caused by operator error
Hydraulic cylinder rods turn black
Hydraulic cylinders - checking rod straightness
Proactive maintenance for hydraulic cylinders
The top four causes of seal failure in hydraulic cylinders
Pressure intensification in hydraulic cylinders
How to test hydraulic cylinders
The effect of temperature on static hydraulic pressure
How to reduce hydraulic cylinder repair costs
How to deal with bent hydraulic cylinder rods
How to solve hydraulic cylinder squeal
How to store hydraulic cylinders - safely
How to store hydraulic cylinders - Part 2
Thermal expansion and pressure intensification in hydraulic cylinders
Straight talk about bent hydraulic cylinder rods

Hydraulic Pumps
How to prevent 'dry' starting of hydraulic pumps
The anatomy of a hydraulic pump failure
Hydraulic pump life cut short by particle contamination
The anatomy of hydraulic vane pump failure
Hydraulic load sensing control explained
Power saving with hydraulic load-sensing control
A serious consequence of over-pressurizing your hydraulic system
Hydraulic power unit problem highlights the importance of hydraulic pump testing
A strange hydraulic pump problem - but true!
How to determine hydraulic pump condition using volumetric efficiency

Hydraulic Motors
Hydraulic motors - how dry starts damage them
Understanding hydrostatic balance
Hydraulic repair using aftermarket hydraulic parts
Temperature shock of hydraulic motors and how to avoid it

Hydraulic Valves
Why hydraulic valve solenoid coils burn-out
How to configure mobile hydraulic valves using power beyond
Hydraulic valve failure caused by cavitation
How to nail hydraulic logic element leakage
How to control decompression in hydraulic press circuits
An important fact about hydraulic spool valves

Hydraulic Oil
Why you should record all hydraulic oil top-offs
Adding hydraulic oil - without the dirt
Hydraulic fluid - getting the viscosity right
High hydraulic fluid temperature - how it causes premature failures
Biodegradable hydraulic oil - its application and use
The true cost of hydraulic oil leaks
Hydraulic system oil types and manufacturers' recommendations
Which hydraulic oil should I use?
How to remove water from hydraulic oil
How to deal with air contamination of hydraulic oil
If you have to change your hydraulic oil - then do this ...
If you HAVE to change your hydraulic oil ... part 2
How to consolidate your hydraulic oil inventory
How to make your hydraulic oil last longer

Hydraulic Filters
Hydraulic pump and motor case drains - filter with caution
Hydraulic filters that do more harm than good - Part 1
Hydraulic filters that do more harm than good - Part 2
Hydraulic filters that do more harm than good - Part 3
Hydraulic filter condition monitoring
What to do if your hydraulic filters are 'clicking'

Hydraulic Hose and Tube
Hydraulic hose - failure costs and prevention
How to flush a hydraulic system
How to put the brake on water hammer in hydraulics
Something to think about next time you change a hydraulic hose!

Hydraulic Fittings and Adaptors
Hydraulic fitting selection the key to leak-free hydraulic plumbing
How to convert 37-degree hydraulic fittings into zero-leak connections
How to deal with hydraulic and pneumatic leaks

Hydrostatic Transmissions
Hydrostatic transmissions: making sense of case drain flow - Part 1
Hydrostatic transmissions: making sense of case drain flow - Part 2
Hydrostatic transmissions: making sense of case drain flow - Part 3
Is this problem destroying your hydrostatic transmission?

Hydraulic Troubleshooting
Would you pass this simple hydraulics test?
How to master hydraulic troubleshooting
The trouble with hydraulics troubleshooting
The value of the humble hydraulic symbol
Hydraulic system troubleshooting - check the easy things first
Hydraulic troubleshooting basics
How to avoid hydraulic troubleshooting mistakes
How to troubleshoot hydraulic cylinder drift
Hydraulic troubleshooting: do as I say - not as I do
Hydraulic troubleshooting tools
How is your hydraulic heat exchanger connected?
Are you sure your hydraulic machine is broken?
Hydraulic diagrams you can't do without
Solving hydraulic problems: whatever it takes?

Hydraulics Maintenance
You can't fix stupid - but your can avoid hydraulic failures due to memory lapse!
Make sure YOU know the 'animal' you're dealing with
How well do YOU know YOUR hydraulic equipment?
How to solve hydraulic system overheating problems
Hydraulic press failure illustrates the importance of scheduling pump change-outs
How to reduce hydraulic system noise
How to source aftermarket hydraulic components
Priority number one in hydraulics maintenance
Anatomy of a hydraulic maintenance failure
Hydraulic equipment reliability - begin with the end in mind
Hydraulic equipment reliability - begin with the end in mind - Part 2
Confessions of a hydraulic equipment manufacturer
Mechatronics and what it means for hydraulics
Hydraulic maintenance lessons from the Qantas mid-air emergency
One type of hydraulic system you don't want!
The bitter-sweet nature of hydraulics maintenance
How to tell if your hydraulic equipment is 'sick'
A simple piece of advice that could literally save your life

Hydraulics Articles in Spanish
El Valor de un Sencillo Simbolo Hidraulico
Resolviendo Problemas de Sobrecalentamiento en Sistemas Hidraulicos
Una Seleccion Correcta de Conexiones: La Clave Para Una Instalacion Hidraulica Libre de Fugas
Determinando la Condicion de una Bomba Hidraulica, Utilizando el Concepto de Eficiencia Volumetrica
Combatiendo la Contaminacion con Aire de un Fluido Hidraulico
Combatiendo la Contaminacion con Agua de un Fluido Hidraulico


Hydraulic accumulators
Hydraulic cooling and heating
Hydraulic cylinders
Hydraulic drive calculations for vehicles
Hydraulic filters
Hydraulic fluids
Hydraulic pumps and motors
Hydraulic reservoirs
Hydraulic valves
Hydraulic winch drive calculations
Orifices in hydraulic systems
Velocity and pressure drop in hydraulic hoses and pipes


Conversion factor tables
Hydraulic fittings
Hydraulic gear pump displacement calculation
Hydraulic hose
Hydraulic seals
Hydraulic symbols
Hydraulic system start-up procedures
Hydraulic tubing
Hydraulic vane pump displacement calculation
SAE hydraulic port flange dimensions
SAE hydraulic pump and motor mounting flange and shaft dimensions

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"This book has the potential to save many organizations lots of money. It should be on the bookshelf of every engineer, supervisor, planner and technician that deals with hydraulic equipment... it's worth its weight in gold." Find out more

Alexander (Sandy) Dunn
Plant Maintenance Resource Center