Dusty
environments can pose a challenge for overhead conveyors used in industry and logistics.
When particles settle on conventional metal bearings, deposits can reduce
smooth operation and, in severe cases, cause failure. To address this issue,
igus has launched a new hybrid ball bearing from its xiros series.
Made from
stainless steel and high-performance plastic, the bearing enables
lubrication-free and dirt-resistant operation while supporting loads of up to
39 kg.
In industry
and logistics, goods and workpieces need to be transported between production
and storage areas quickly while using minimal space. Overhead conveyor
technology is commonly used for this purpose.
“Design
engineers are currently endeavouring to make these systems more efficient as
users are increasingly less accepting of downtime and breakdowns. Even short
interruptions can cause high costs and delays,” said Marcus Semsroth, Head of
Business Unit xiros Polymer Ball Bearings at igus.
One way to
improve efficiency is by replacing the ball bearings used by trolleys moving on
aluminium profiles.
“For this
purpose, we have launched a new hybrid ball bearing from the xiros series. It
makes overhead conveyors more fail-safe and requires less maintenance,”
Semsroth added.
In most
overhead conveyors, carriages move on standard metal ball bearings. These are
degreased and filled with low-friction oil to reduce friction. However, the
low-viscosity oil can leak through the seals and attract particles,
particularly in dusty environments such as the textile industry.
The
resulting deposits can affect smooth operation and, in the worst case, lead to
failures.
“To get to
grips with this problem, we have designed the new hybrid ball bearings in such
a way that they work without lubrication,” explained Semsroth.
The use of
high-performance plastic xirodur B180 enables low-friction dry operation,
reducing susceptibility to dirt and eliminating the need for maintenance. The
outer race also runs with low friction on aluminium profiles. Steel bearings
generally require an additional plastic outer and are therefore more complex
and expensive.
“In the
past, many design engineers of overhead conveyors expressed the wish to switch
from steel ball bearings to plastic variants from igus. In many cases, however,
this was not possible as the load capacity of solid plastic bearings is too
low,” Semsroth said.
To address
this limitation, the inner race, the most critical component of the hybrid
bearing where the highest surface pressure occurs, is made of stainless steel.
The load balls are also made of stainless steel, but from a different alloy.
The cage is
made from iglidur J3, a high-performance polymer containing additives designed
to improve strength and sliding properties. This combination enables the hybrid
bearing to support loads of up to 39 kg.
“Although
metal ball bearings with a load capacity of 80 to 100kg are stronger, the new
hybrid ball bearing is suitable for a wide range of applications in industry
and logistics, for example in furniture construction or packaging systems.”
The ball
bearings are available in three variants with inner diameters of 8 mm, 10 mm
and 12 mm. A version with a spherical outer race is also available to enable
smooth operation in aluminium profiles.