Page 41 - Commercial Vehicle Engineer - June 2021

Wheely-Safe's device can detect a nut coming loose before
a driver is aware of it
WHEEL NUT SECURITY
“It is an incident-based thing, it isn’t a time-based thing. It is about spotting the incident that happens on the road on a Wednesday afternoon”
But, as Wheely-Safe’s Broadfield notes, vehicles can have diligent inspection routines, and regularly torque the wheel nuts correctly, but incidents of wheels loosening can still happen.
For instance, wheel loss is more common in off-road vehicles. “If a truck is loaded to 40 tonnes and they go
down a pothole and all the weight goes through one side or one axle and they have twin wheels and those start working independent to each other, then it can start the process of a wheel nut coming loose,” says Broadfield.
“Other problems occur when too much is when the wheels are on the limit, or when they twin them up, and as soon as you twin stuff up you have more surfaces to play with and you can have the two wheels themselves working against each other if they are not perfectly centred and nuts can just work loose.”
Tech solutions
However, there are solutions that can
aid the detection of any wheel nuts coming loose. Wheely-Safe has devised a displacement sensor that sits in a bracket between two wheel studs. “When it is all torqued up that sensor has quite a lot of compression force on it, but the bracket forces it against the wheel rim and that closes a switch,” explains Broadfield. “To open the switch, you need just below one millimetre of movement.
“There is also a heat sensor in there for rim temperatures as that’s a really good indicator for what’s happening behind the wheel with the braking system and the hubs, which is also a valuable element.”
Once the switch has been opened,
a message is sent, via a light on the dashboard, to the driver. A message can also be sent to a transport office, although Broadfield advocates always having a
driver alert to prevent any potential delays in addressing a problem. This alert goes off before the driver is even aware there is a problem with the wheel nuts, Broadfield adds. The driver can then quickly find a place to stop before the loose nut has a chance to become
a problem.
Things like fluorescent WNI are useful
to show if a nut is slowly loosening, but sometimes they can loosen very quickly, Broadfield adds. “This device catches those that do work loose quickly,” he says.
“It is an incident-based thing, it isn’t a time-based thing. It is about spotting the incident that happens on the road on a Wednesday afternoon.”
As Broadfield says, the combination of technology, along with daily driver checks and regular scheduled maintenance
for wheels and nuts, should ensure
that operators do not add to the wheel loss statistics.
COMMERCIAL VEHICLE ENGINEER > JUNE 2021 41