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BY JEAN HILLER
Winterizing your heavy construction equipment
isn’t just about readying a machine for
colder temperatures. It also involves the necessary
actions to take once the temperature
drops, snow falls and ice covers the ground.
In fact, planning ahead is just one small part
of a three-step winterization process that
includes preparation, prevention and operation.
The preparation stage of winterizing an excavator
is just that — making the excavator
ready for use in subzero temperatures, snow,
freezing rain, ice or other winter-related
weather conditions that may adversely affect
its performance or condition.
Today’s synthetic oil and multi-grade
oil covers the range of temperatures experienced
throughout most of the year; however,
winter temperatures in Canada, which
typically dip below zero degrees, require extra
attention. “If you’re working in Canada
where winter lows can reach 40 degrees
below zero, then you need to switch to an
arctic oil,” says Roberto Bogdanoff, director,
key accounts customer solutions, Volvo
“It comes down to the viscosity of the oil.
If you use a thick oil in the winter, it takes
longer for the lubrication system to be fully
affected, causing the engine to work with
very low lubrication for five to 10 seconds.
However, with multi-grade oil, even under
a wide range of temperatures, the viscosity
doesn’t change much. So you start the engine,
and your lubrication system is active
within one or two seconds. And if you have
synthetic oil, it’s basically active immediately,”
The viscosity rule also applies to fuel, and switching to a winter
blend of fuel will prevent diesel fuel from gelling. Other fluids needed
for excavator operation that are susceptible to the cold include lubricants,
antifreeze, hydraulic fluid and coolant. These areas should
follow the manufacturer’s recommendation for colder climates, but
the general rule of thumb for preparation also applies.
It’s also a good idea to check windshield wipers and replace wiper
fluid with a de-icing solution to improve visibility.
The preparation stage is the ideal time to make sure excavator
batteries are in good working condition. “Batteries can be up to 50
per cent weaker in an extremely cold environment. Add that to an
already weak battery and suddenly you’ve got a machine that won’t
start,” says Bogdanoff. Use a battery tester to check voltage and watch
for performance signals, such as a sluggish or slow engine turnover.
The prevention stage of winterizing your excavator requires actions
that will eliminate or reduce the chance of downtime or
damage to the machine. Unlike the preparation steps that must
be done before the winter weather arrives, these actions should
be taken after the temperature drops, the snow falls or the ice
First and foremost is a visual inspection of the machine, specifically
the hydraulic hoses, which are particularly sensitive to wintry
conditions. The lifespan of a hydraulic hose is typically 7,000 to
9,000 hours, but freezing temperatures can degrade the composition
of the rubber tubing, making it stiff and brittle. Replace hoses with
cracks or weak spots that could spell disaster when further stressed
by hot hydraulic oil.
“Once a hydraulic hose breaks, you can have hundreds of gallons
of oil on the ground in a matter of seconds,” says Bogdanoff. “Not
only do you have costly cleanup and repairs, but you might also face
a fine for a hazardous material spill.”
Hydraulic cylinder rods are another component of the machine
where prevention is important. Repeated exposure to snow, ice and
salt brine mixtures can cause chrome to rust over time. Fully retracting
hydraulic cylinder rods when possible can help decrease the
potential for damage. Steam washing the excavator exterior regularly
will help remove salt build-up, which can wreak havoc on 25 tonnes
of heavy construction equipment.
Snow and ice can interfere with movement of the boom and arm
and should be cleared from the machine exterior before operation. “I’ve
seen a hydraulic cylinder break because the compartment was full of
snow. The operator didn’t clean it off and started moving the machine.
The cylinder started compressing the snow. All of a sudden it didn’t
have any more room to move and it broke,” says Bogdanoff. “Snow, as
fluffy as it is, when you start compacting it, it gets really hard.”
Steps to the cab should also be cleared of snow and ice to ensure
safe entry and exit for the operator. A working heating system will
also keep freezing temperatures outside, not inside the cab.
The operator is also key to the operation stage of winterization, when
the machine is actually engaged in work. Operating an excavator in
the winter requires adapting to the conditions, including winter tires
(on wheeled excavators) and buckets designed specifically for frozen
ground. Bogdanoff recommends making sure wheeled excavators
have proper winter tires and exercising caution when operating a
crawler excavator on frozen surfaces.
“The steel track acts just like an ice skate; it can slide,” says Bogdanoff.
“It’s amazing how such a large piece of equipment can easily
slide on the ice.”
Even the basic steps of starting up and shutting down an excavator
require special attention in frigid winter weather. Before any work
can be done, the excavator engine and hydraulic systems must first
be warmed up.
“Once the engine is stabilized, after idling about five minutes,
you need to start moving the machine slowly to warm up the whole
system and hydraulics, not just the engine,” says Bogdanoff. “Once
the temperature indicators in the cab reach normal range, you can
start working at full power.”
The excavator also requires extra time for a cool-down period
before shutting down the machine. Bogdanoff recommends letting
the machine idle for 90 seconds before shutting down power.
As a final step in the process, top off the fuel tank at the end of
the workday. This prevents condensation from forming in the tank,
which can lead to water in the fuel line — a problem that can cause
extensive damage to the engine — making winterizing an excavator
a moot process.
In some instances, and areas of the country, it simply doesn’t make
smart business sense to operate an excavator during the winter
months. Storing an excavator requires many of the same steps as
those recommended for winterizing a machine.
• Replace fluids and fuels with winter blends.
• Use manufacturer-recommended lubricants, antifreeze, hydraulic
fluid and coolant.
• Retract hydraulic cylinders.
• Fill fuel tank.
• Clean excavator exterior of dust, dirt, debris, snow and ice.
• Store equipment inside when possible to avoid the damaging
effects of snow, ice and salt brine.
Following the three-step winterization process of preparation,
prevention and operation will help your excavator deliver day-afterday
dependability through the winter … spring, summer and fall.
Ontario looks at a new
technique to improve
BY ANDREW MACKLIN
Concrete Pavement Preservation techniques
are not new in Canada and the U.S.
It has been almost 50 years since grooving
and grinding was first demonstrated on
concrete roads in California in 1965. But
in Canada, provincial transportation ministries
have started to appreciate the inherent
value of using this technique to extend
the life of concrete highways.
WHAT IT INVOLVES
Diamond Grinding involves the removal
of the thin surface layer of hardened concrete
using diamond saw blades. The removal
of that layer helps to improve surface
friction and blend together surface
irregularities without affecting overhead
clearances. The grinding process can be
done in off-peak hours and is environmentally
Ultimately, the process provides an estimated
60%-70% improvement over the
pre-grind profile of the road.
Diamond Grooving is used to help provide
stronger water dispersal on concrete
and asphalt roads. Groover blades are
spread farther apart that grinding blades
to provide relief for water to escape, similar
to that of the commercial tire industry.
The groover blades can be oriented in either
a longitudinal or transverse orientation
depending on user preference.
The residue left by both the grinding
and grooving processes is slurry. All production
grinders have a standard CGR
vacuum as part of the operation. The slurry
is vacuumed off of the roads and taken
to nearby settling ponds where the sentiment
can be separated, dried and recycled
and the water re-used.
The result of using diamond grinding is a significant reduction
in splash and spray, hydroplaning and wet weather accidents by
up to 70 per cent according to data from the International Grooving
& Grinding Association (IGGA).
TECHNIQUE IN ACTION
From 1989 to 1991, the Ontario Ministry of Transportation
(MTO) placed concrete pavements for Highway 115 under
freeway twinning projects. The twinning project involved approximately
27 two-lane kilometres of concrete pavement. The
56.7km highway runs north/south, linking the city of Peterborough
to Toronto via Highway 401.
According to information provided by MTO: “While minor
maintenance had occurred, the first major intervention after this
was in 2007 by way of a Concrete Pavement Restoration (CPR)
Contract which included full and partial depth slab repairs, selected
crack sealing and stitching and dowel bar retrofit. This
contract was followed by similar CPR contracts in 2008, 2009,
“In 2011, a Contract was let for Diamond Grinding all concrete
pavements on Highway 115. This process removed the
remnants of the original transverse grooved (tined) surface and
placed a regular longitudinal corduroy texture.
“In June of 2013, the tender for Diamond Grooving of concrete
pavements on Highway 115 was issued. The tender opening
was August of 2013. The tender also included extensive resealing
of concrete joints.”
The diamond grinding technique has been used on Ontario
highways before, but grooving was a new concept for MTO. John
Roberts, who is the Executive Director of the IGGA, originally
pitched the idea of diamond grooving in combination with diamond
grinding to the Ministry.