To: Colleagues far and wide
From: Reliability Engineer, Gordon Tattershall
Re: Conveyor idler sealing assessment –
Locating products and practices that add
benefits to life cycle costs, or sustain or
increase production uptime is necessary for
viability in this decade, and on this occasion I
am writing to share some of my latest findings
on a product that may be worth while your
consideration. Any feedback would be welcome.
In my experience, replacement conveyor idlers
contribute to a significant amount of the cost
of conveyor maintenance, and even more so where
product carry back or water accumulates along
the trough idler.
The predominant failures occur from
contamination effecting the bearing
functionality, idlers becoming jammed by product
being caught between the frame and idler, and
the rolling surface becoming preferentially worn
whether from abrasion or corrosion.
I have seen several different conveyor idler
constructions and was impressed by the one
manufactured in Europe and distributed by
The following photographs are of an idler I have
partly disassembled to form an opinion on the
potential of contamination entry to the bearing
when in service. The outer running surface or
thick HDPE has a number of advantages over a
thin steel shell.
The shaft sealing arrangement consists of a
wiper seal and pre lubricated multiple chevron
rings that rub on a sleeve. The sealing
arrangement is located in a bore by a moulded
feature that positively locates it. The
manufacturer has undertaken laboratory test work
to verify the functionality and repeatability of
the sealing arrangement.
The bearing is inboard of the sealing
arrangement mounted in a stiff moulded section
of the idler. The torque to rotate the idler
measure with a spring gauge and string was so
low it wasn’t clearly determined due to the
discrimination of the spring scale used.
The running surface is HDPE on a steel
substrate. The surface finish has a
manufacturing profile may assist in the
dispersement of water.
After disassembling the sealing arrangement I
believe it could be reasonably expected to
increase the Mean Time between Failure of idler
bearings, whilst the idler perimeter also will
be less subject to the effects of surface wear
The idler is available in Australia from
EU-Roller A.P.I who supplied a sample for my
personal assessment. The contact for further
enquiry is Mr Andrew Stevens.
email@example.com or for further
information (includes a sizing template for
retrofitting ) is a website
The following series of photographs have been
taken to show some of the construction aspects
of the EU Roller so you can gain a greater sense
of what may be a difference from the typical
steel idler. The idler was quite robust and this
one I inspected has been well made.
Trust this may be of use for background
knowledge as we all strive for knowledge and
opportunities for continuous improvement.
EU Roller API as
End view of roller
showing the shaft wiper seal and the removed rubber shaft cap
Seal assembly showing
lubricated chevron rings and outer wiper seal
View of HDPE idler
showing internal end boss and illustrating location of seal assembly
Internal view of end
End view showing
shaft sleeve and bore for sealing assembly
Side view of removed
seal assembly showing protruding wiper seal and locking feature
Seal is securely
located requiring a reasonable force to disassemble