1. Causes of Hydraulic Pump Failures
"What could be the reason for a hydraulic pump failure and how can we prevent such failures in the
future?"
A hydraulic pump failure can be caused by a number of factors. There are several different types of pumps
available on the market, and each can have its own specific failure mode. Of course, certain failure modes
are common to all types of pumps. Some of these failures can be caused by poor system design, using
low-quality fluids and/or poor contamination control.
The best way to prevent future failures is to ensure that you are using quality hydraulic fluids. Keep in
mind that the fluid is the single most important component of a hydraulic system, so always use high-
quality hydraulic fluids with the correct viscosity.
Hydraulic fluids should also be kept clean, cool and dry. This is highly important. One of the ways you can
do this is through quality filtration. Filters should be selected only if they achieve the target cleanliness
levels that have been set for the fluid in the system. Also, use quality filters in locations that assure the
required protection and upgrade the filters when necessary.
In addition, consider the possibility of using offline filters, because the cost of removing dirt is often much
less in an offline mode than trying to do everything in a pressure-line filter location on the hydraulic
system.
It is estimated that between 70 to 80 percent of hydraulic system failures are from contamination, with
particle contamination making up the largest portion. Therefore, it is best practice to regularly perform oil
analysis with particle counts.
Remember, the hydraulic pump is generally the most expensive component on a hydraulic system. It has
the highest reliability risk, the highest contaminant sensitivity risk and the ability to cause chain-reaction
failures. In other words, when the pump starts to fail, it starts to kick out debris into a debris field
downstream of the pump. If there is not a good filter downstream, this debris moves on to other
components like valves and actuators, and can lead to damage in those components as well.
Be wary of quick-fix solutions like switching to costly synthetics and expensive filtration systems. Instead,
provide solutions to the problems that exist. It is critical to set the proper cleanliness and dryness targets
and to develop contamination control procedures that will allow you to meet those targets. By doing so,
you should greatly reduce and possibly eliminate your pump failures.