The 2 Ways To Get Essential Hydraulics Knowledge

radial piston motor failureFor heavy equipment owners at least, there are only two ways to get the essential hydraulics knowledge they need. The first way is via their preferred repair shop, in exchange for helping to pay for the owner’s holiday home. This is ‘after the event’ education. And it’s the most expensive education anyone can get. The second way is to get and study a couple of good books on the subject. This is ‘upfront education’ and compared to ‘after the event’ education it can be got for pennies on the dollar.

A question I received from a heavy equipment owner recently … continue reading »

The Life Cycle Bathtub Curve For Hydraulic Components

axial piston pump failureThe original life cycle bathtub curve was based on the cycle of human life. And at some point last century it was adapted by reliability engineers working in the electronics manufacturing industry to graphically represent the failure rate of their products. As you can see from its depiction below, the Observed Failure Rate-the top, bathtub curve, is the product of the three curves below it: Infant Mortality Failures, Wear Out Failures and a near constant rate of Random Failures.

One glance and it’s obvious the bathtub curve is just as pertinent to the life cycle of hydraulic components as it … continue reading »

A Word About Retermination of Hydraulic Hoses

hydraulic hoseClause 5.4.6.5.1 a) of ISO 4413:2010 “Hydraulic fluid power – General rules and safety requirements for systems and their components” states: “hose assemblies shall be constructed from hoses that have not been previously used in operation as part of another hose assembly and that fulfil all performance and marking requirements given in appropriate standards;”

This means squeezing a new end onto a hydraulic hose that has previously been in service contravenes ISO 4413:2010. In the majority of cases, the practical implications of this directive are not burdensome. After all, in most situations, the hose end outlasts the hose itself.… continue reading »