Features Aggregates Technology
Halite, MSOE test rod wipers for dust

Jan. 29, 2015, Wixom, Mich. – First-of-its kind test for rod wipers developed by Halite and MSOE sets new industry criteria for contaminant exclusion.

Jan. 29, 2015, Wixom, Mich. – First-of-its kind test for rod wipers
developed by Halite and MSOE sets new industry criteria for contaminant
exclusion.

Hallite Seals Americas, Inc., a leading global manufacturer of
high-performance hydraulic sealing solutions, announced today the
successful development of a new test procedure for assessing the amount
of dirt and dust that enters a typical hydraulic system through the rod
wiper. Developed in cooperation with Milwaukee School of Engineering’s
(MSOE) Fluid Power Institute, the test breaks new ground because it
features a novel methodology for measuring dry particles attributed to
being a major cause of hydraulic system inefficiency, degradation and
failure. It fills a critical need within the cylinder manufacturing
industry.

Most hydraulic systems employ numerous cylinders which function
like a syringe, drawing in contaminants. The rod wiper located in the
sealing configuration of a hydraulic cylinder is designed to limit the
ingression of dirt, dust and grit, making it one of the most critical
system components. However, there is no specific ISO method for testing a
rod wiper’s ability to prevent >4, >6 and >14 micron particles
from entering the hydraulic system. These microscopic particle sizes
are most damaging to hydraulic systems as referenced in ISO 4406 for
coding contamination levels in hydraulic fluids.

“The MSOE rod wiper test uses an online particle counting method
instead of traditional gravimetric measurement where particles are
weighed,” says Chuck White, Business Development Manager for Hallite.
“The particle count approach provides a more complete and accurate
assessment of contaminants than weight because two samples can have the
same gravimetric weight in oil, but one may contain many more dirt
particles than the other indicating much greater potential for damage to
precision components. This new method raises the bar on keeping solid
contaminants out of the system now to avoid problems later.”

MSOE used the SAE J1195 standard combined with best practices
to establish a baseline for developing the rod wiper test procedure. A
rig was built in the MSOE test lab and parameters such as duration,
cycle rate, pressure and temperature were set using input from hydraulic
cylinder manufacturers to best simulate the rigor of actual field
conditions. It took eight months of development, verification, trials
and adjustments to establish a repeatable test procedure. Once the new
procedure was completed and proven, MSOE tested the Hallite 520 and 820
wipers against two competitors.

The test procedure involved installing the rod wiper into the
specified test fixture, heating the hydraulic circulation fluid to150˚F,
pumping the oil over the top of the rod and letting it drain down into
the reservoir while circulating high-velocity particles (ISO 12103-1-A4
Course Test Dust) of contamination in the chamber. The objective was to
count how much dirt and grit got past the wiper. Based on the conditions
and method used, data suggests that the Hallite 520 and 820 wipers
allowed less than one half the amount of contaminant from entering into
the test system compared to competitive wipers that were tested.

A White Paper has been produced for the MSOE test. And a graphic
animation of the test depicting how it was conducted was created. Both
are available upon request.

“Hallite has a reputation as a trusted brand for wiper
technology, but we needed competitive third-party validation for the
integrity of our material and design,” says White. “We are very excited
about the performance results because they demonstrate how our products
work in some of the most aggressive field environments. Also, working
together with MSOE and key customers to develop and conduct a test of
this quality is invaluable as it forged a three-way partnership that
emphasizes the importance of rod wipers and gives Hallite an opportunity
to demonstrate our continued commitment to understanding and developing
technologies to improve the effectiveness of hydraulics systems.

Finally, by cooperating with one of the leading academic fluid
power research laboratories in the nation where students are building
and managing the mechanical functions for test fixtures, Hallite is
providing real-world interaction to help the next generation of
hydraulics engineers learn more about seals and how they interact. This
paves the path for innovative future testing methods.”

Hallite is a leading manufacturer of high performance
hydraulic sealing solutions, such as wiper seals and other customer
gaskets, rubber and plastics parts. For over 100 years Hallite has
manufactured a wide range of products for a variety of markets including
mining, off-highway, construction, agriculture and material handling.
Engineered in a wide variety of advanced materials, the full range of
products are readily accessible through Hallite’s global manufacturing
presence and a worldwide network of service partners. Hallite is a
member of the Fenner PLC Group of companies. For more information about
Hallite, visit www.hallite.com.

Fluid Power Institute™
MSOE’s Fluid Power Institute™ (FPI) has been a pioneer in motion control
and fluid power education since its inception in 1962. FPI has active
programs in fluid power systems design, electro-hydraulics, test &
evaluation, fluid development and contamination control. FPI recently
added a new off-campus 12,500sqft laboratory facility to support the
R&D needs of the fluid power Industry. This high-bay laboratory has
drive-in access, reconfigurable workspaces, and multiple power units for
realistic endurance testing of fluid power equipment. For more
information, visit www.msoe.edu/fpi.