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Preparation,

Prevention and

Operation

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.

PREPARATION

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

Construction Equipment.

“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,”

says Bogdanoff.

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.

PREVENTION

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

accumulates outside.

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.

OPERATION

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.

STORING

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

concrete highways

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

friendly.

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,

and 2010.

“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.