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Canada's “Rock to Road” Magazine
May/June
2007 Issue
For a copy of the issue
that contains these articles with colour photos, click
here.
Portable
spread delivers high productivity
By Andy Bateman, Engineering
Editor
An
aggregate crushing contractor combines proven production practices with
advanced crushing technology to achieve high productivity.
On the face of it, efficient aggregate production should be a simple
process. Take a natural or recycle raw material and use screens to sort
it into desired sizes, crushing large material into smaller sizes where
necessary. In practice, many variables impact on the efficiency of this
process. Some, such as equipment selection and set up are within the
control of the producer while others, the physical and chemical properties
of the deposit for instance, are not. Those producers who consistently
achieve high productivity appear to do so by integrating well proven
production practices as well as modern technology into plant set ups.
Aggregates & Roadbuilding Magazine saw one such plant on a recent
site visit.
The portable spread was working in the
Pinchin pit near Erin, Ont. where crushing contractor Flesherton Concrete
Products was producing granular base and asphalt aggregates for pit
owner Aecon Materials. The spread included two crushing stages, two
screening stages, associated conveyors, control/ genset trailer and
mobile support equipment.
Plant supervisor Greg Hammer explained
that the Pinchin deposit contains well-graded material with occasional
pieces up to 250 mm in diameter. In normal operation, a Caterpillar
980G wheel loader discharged pit run into the feed hopper of an ELRUS
combination feeder, screen and jaw primary plant. Material from the
hopper was conveyed to the 6x20 primary screen, fitted with 52 mm and
25 mm screen cloths on the top and middle decks respectively. Minus
25 mm passing the screen’s bottom deck was stockpiled by
a Strada Industries stacker as Granular B finished product. Meanwhile,
oversize from the screen’s top deck was directed to the ELRUS
20x36 jaw crusher and crushed to a maximum size of between 64 mm and
76 mm.
At the same time, the minus 52 mm to plus
25 mm material retained on the bottom deck was bypassed around the jaw.
The jaw crusher run and crusher bypass material both discharged onto
a common side conveyor off the primary plant and conveyed to a feed
bin ahead of the secondary plant.
At the secondary plant, material from
the feed bin was conveyed to a 6x20 ELRUS secondary screen fitted with
44 mm, 22 mm and 4.8 mm screen cloths on the top, middle and bottom
decks, respectively. In this application, the cloth on the top deck
provided impact protection and also helped to spread feed material more
evenly across the lower two sizing decks. All material larger than 22
mm was directed to a Sandvik H3800 Hydrocone crusher in closed circuit
with the screen, while minus 22 mm to plus 4.8 mm was stockpiled as
HL8 finished product and minus 4.8 mm stockpiled as screenings.
Hammer reports an average running production
rate of 500 tonnes/h for this set up, with an estimated product split
of 310 tonnes of Granular B, 100 tonnes of HL8 and 90 tonnes of screenings.
Even when producing Granular A, an average running production rate of
460 tonnes/h is reportedly being achieved. Equally important, these
impressive rates are being achieved in conjunction with cubicle product
shape and high plant availability.
Hammer points out, in order of process
flow, factors contributing to this good performance. “At the feeder
screen jaw plant, the input rate is increased by allowing material smaller
than 52 mm in the feed to bypass the jaw crusher. This means the jaw
is not loaded with small material and avoids any unnecessary crushing
or fines generation within the jaw. Also, by producing Granular B directly
off the primary screen, finished product is taken out of the system
as soon as possible.”
The feed bin to the secondary plant serves
a number of purposes. For one thing, it enables the plant operator to
carefully control the flow rate of material going into the secondary
plant. This degree of control allows the plant operator to fine tune
material flow rates in the secondary plant, resulting in high production
rates and smooth running without overloading the secondary crusher,
screen or conveyor belts. The bin also acts as a buffer between the
primary and secondary plants, absorbing surges or breaks in the flow
of material from the primary plant. As a result, a steady flow of feed
is maintained to the secondary plant.
At the secondary plant, the Hydrocone
is working in almost ideal conditions, with steady feed and a reduction
ratio of about 3:1 to consistently produce a well shaped cubicle product
at a high production rate.
“We set the primary jaw fairly tight
so that the largest size in the feed to the Hydrocone is about 75 mm,
or about three times larger than the maximum particle size in the HL8
finished product. Finally, the Hydrocone is equipped with an automatic
crusher control system.”
According to Sandvik Rock Processing,
the ASRi intelligent crusher control system is equipped with an advanced
sensor to measure the pressure at which the crusher operates. This is
said to lead to a more accurate indication of crusher performance and
help the operator to optimise the crushing force. It also protects the
crusher from overloads and so helps prevent stoppages.
The system also allows up to twenty different
crushing programs to be stored, with the user able to choose between
three operating modes for each program. The first mode allows the operator
to enter a specific close side setting (CSS) to keep the crusher running
at the same setting. Should an overload occur, the crusher opens to
relieve the overload and returns the mainshaft to the desired position
when the load reverts to normal. The second mode regulates the crusher
load setting to optimize crusher productivity. If, for instance, the
highest load level is selected, the CSS will always be the smallest
possible, resulting in maximum reduction for a particular application.
In the third mode, the system can be set
to a multi-CSS function in which the crusher automatically switches
between two different settings to give two product curves. This switching
takes place on a time share basis, such that the end product contains
the desired proportion of finer and coarser materials.
The Process Optimization Tool (POT) is
a further system refinement and utilises three laboratory test results
to predict product curves and qualities for different crusher settings.
The user can also study the effect of a change in set point or anticipate
the consequences of switching between different feed materials. Other
system features include intelligent wear compensation, reducing the
need for calibration, while a single press of a button does metal-to-metal
calibration.
Additional functions include alarm, event
log, operating data and historical data. In large operations with multiple
crushers, the ASRi system on each crusher can communicate with a higher
level system by way of an Ethernet connection. The basic requirement
for using an automatic regulator like the ASRi system is a crusher with
hydraulic adjustment setting that allows for repeated rapid setting
adjustments during operation with the crusher under full load. All hydrocone
crushers are said to meet this requirement.
The business activities of the Flesherton
Concrete Products Inc. group, known as Fleshcon, include contract crushing,
ready mix concrete with plants in Flesherton and Stayner (Clearview
Concrete) and the six sand and gravel pits of Mike Croft Contracting
Inc.
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top
Canada's
Top 25 Operations
By Andy Bateman, Engineering
Editor
“Steady
away” could be the theme for this year’s exclusive report
on Canada’s biggest aggregate operations.
In
compiling this year’s rankings of the country’s Top 25 Aggregate
Operations, one of the most noticeable aspects is the similarity to
last year, with most operations reporting 2006 production tonnage within
a few percent of the 2005 figure. The top of the list is particularly
stable with all of the country’s top five aggregate operations
reporting 2006 production within 2 per cent of 2005. The order of the
top five also remains unchanged despite the inclusion of operations
serving very different markets. Elsewhere, year over year changes are
less than 5 per cent although there are some exceptions. In British
Columbia, the Cox Station Quarry of Mainland Sand & Gravel reported
8 per cent year over year growth to rise three spots from 14th to 11th.
On the other hand, production drops of 10 per cent or more were reported
by the Milton and Acton quarries of Dufferin Aggregates (Ontario), the
St-Dominique Quarry of Les Carrieres de St. Dominique and the St-Eustache
Quarry of Les Carrières St-Eustache (Quebec), as well as the
Lower Cove Quarry of Atlantic Minerals in Newfoundland.
The western provinces continue to lead
the way in terms of demand and producers there report ongoing investment
and process changes to boost production capacity. Harold Diggon, operations
manager for Texada Quarrying Ltd., Canada’s biggest aggregate
operation and quarry, reported 5.66 million tonnes for 2006, up slightly
from 2005’s figure of 5.59 million tonnes. To increase Texada’s
production, Diggon has put a Mormak 36x48 jaw crusher, complete with
loader dump and belt tie-in, back into service at the aggregate plant
to provide additional primary crushing capacity and back up for the
plant’s Cedarapids 36x48 jaw crusher. On the sales side, 2007
year-to-date numbers have been boosted by shipment of some 450 000 tonnes
of 300 mm minus core rock to Deltaport Constructors Ltd. (DCL) for the
Deltaport Third Berth Expansion Project. Deltaport is the Port of Vancouver’s
largest container terminal, located at Roberts Bank, 40 km south of
Vancouver’s inner harbour. At the Deltaport site, DCL project
manager Dave Basnett explained that the project will extend the existing
dock by 430 m to provide an additional berth at the container terminal
and also expand the port’s real estate by the addition of a large
new reclaim area. The Texada material is being utilised to construct
a dike enclosing the new reclaim area which, once enclosed, will be
backfilled with imported dredged river sand. The dike does double duty
as it also provides an access road to a new tug basin located outside
the reclaim area. At the time of Aggregates & Roadbuilding’s
site visit earlier this year, work on the dike included raising its
height by 3m, placing erosion control material on the outside faces
and constructing a 200 m long leg northwards from of the end of the
dike for the new tug basin.
Construction Aggregates Limited (CAL)
operates Canada’s largest sand and gravel operation at Sechelt
B.C., with reported 2006 production of over 5 million tonnes.
According to Rodger McLean, manager of Vancouver Island & Coastal
Aggregate Operations for Lehigh Northwest Materials Ltd., 2007 promises
to be even stronger with a target 6 million tonnes of production. Sechelt’s
regular customers are stretching pit production capacity and, on top
of that, the operation also shipped 50 000 tonnes of concrete sand to
Hawaii in April, with a second shipment planned for June. To keep up
with this growth, process improvements include the doubling of primary
surge pile capacity and the acquisition of four Caterpillar 773F haul
trucks by Sechelt’s haulage contractor.
Production also remains strong at the
Producer’s Pit, the CAL sand and gravel operation in Victoria
B.C., where 2.3 million tonnes were produced in 2006. McLean adds that
the final extraction and reclamation program for the Producer’s
Pit has been deferred for at least a year by the securing of additional
reserves.
The Cox Station granite quarry of Mainland Sand
& Gravel Ltd. appears regularly in Aggregates & Roadbuilding,
both in the Top 25 report and feature articles. (“B.C. quarry
redevelopment plan creates long term benefits, short term challenges”,
August/ September 2006). Capital investment at Cox Station continues
apace with the recent addition of process and mobile equipment. New
mobile equipment additions include a Sandvik D25KS production blasthole
drill as well as Caterpillar 988H and 980H wheel loaders and a Cat 236B
skid steer loader. Further additions to the mobile fleet acquired on
a rent-to-purchase basis include a Komatsu PC 400 LC excavator, a John
Deere 844J wheel loader, a Komatsu WA 500 loader and a Caterpillar 740
articulated dump truck. On the process side, a 640 m long conveyor has
been installed to complement the recently commissioned over-railroad
load out conveyor. The company has also acquired a portable crushing
plant and shipped it all the way to Cox Station from Nova Scotia. This
portable spread combines a Metso HP400 cone crusher and Cedarapids 6x20
triple deck screen and, rare for a portable plant, now runs on mains
power. This power arrangement is achieved by using a trailer mounted
portable substation with three transformers that can quickly be connected
to mains supply from a nearby drop pole.
Moving east to Alberta, Brian Puchala,
Inland’s operations superintendent for Northern Alberta reports
2006 production of 3 million tonnes for the Villeneuve pit, 30 km northwest
of Edmonton, with a significant increase to 3.42 million tonnes forecasted
for 2007. Continuing very strong regional demand is being driven by
growth across most industry sectors. Major regional roadbuilding includes
further sections of Edmonton’s Anthony Henday Drive, while demand
in industrial, commercial and residential sectors continues to climb.
At the operation itself, two new pits in the area will supply an extra
300 000 tonnes of raw feed to the Villeneuve processing plant. Capital
investments in fixed and mobile equipment here total some $3 million.
New mobile equipment additions including a Caterpillar 345CL excavator
and Caterpillar 988H wheel loader, while process additions include a
Metso GP200 gyratory crusher and a chassis mounted Metso HP300 cone
crusher.
In other parts of the country, capital
investments appear more geared to product diversification and replacement
as well as capacity increase. In Quebec, for instance, Claude Sylvestre,
president of Carriers de St-Dominique, reports that mobile equipment
additions have included Caterpillar 988F and 988B wheel loaders as well
as two 777B haul trucks, while processing equipment include a Trio 54x34
fine material washer. The province’s largest quarry, Carriere
St-Eustache, invested $2.36 million last year in capital equipment purchases
that included a new Freightliner water truck, an Atlas Copco T4BH rotary
blasthole drill, new Terex Simplicity DM-140S 8x24 triple-deck screens
and a new primary feeding system. A new Metso 8x24 triple-deck secondary
screen has been added this year.
Further east, Kim Conrad of Conrad Bros in Dartmouth
N.S. expects the market to remain buoyant for another couple of years
and this expectation is reflected in continuing business investment.
The Dartmouth Quarry produced 1.2 million tonnes in 2006, and changes
here include a fourth Metso HP400 cone crusher, a Caterpillar 980 wheel
loader, a Caterpillar 772D haul truck and a Sandvik D25KS production
blast hole drill. Together with new truck scales and other items, these
expenditures total about $2 million. Continuing east to Newfoundland,
Lloyd Buglar at Atlantic Minerals Limited reports that 2007 spending
plans for the Lower Cove quarry include a new crawler mounted rotary
blasthole drill and a motor grader.
So what changes might 2007 bring to the national
aggregates picture? Potential candidates for next year’s list
include Polaris Minerals’ Orca Quarry, located in B.C. at the
north end of Vancouver Island. This water based sand and gravel operation
went in production in February 2007 and is already supplying major ready
mix concrete producers in San Francisco and Vancouver’s Lower
Mainland area. Another possible 2007 candidate is the Muskeg Valley
Quarry, located in the oil sands region of northeastern Alberta. Owned
by Birch Mountain Resources Ltd, this quarry has recently received a
500 000-tonne order from an oil sand infrastructure project and will
reportedly have a huge annual production capacity of 9 million tonnes
of crushed product.
Click
here to download Top 2006 Aggregate Operations (110kb)
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What's
new in ADTs
Volvo
Full
suspension option for Volvo new E-Series haulers
Volvo CE has rolled out a radical redesign
for its new E-series line of articulated haulers. The new models are
claimed to be the world’s first to offer a suspension system with
automatic leveling and stability control on all wheels. According to
the manufacturer, this ‘full suspension’ provides excellent
off road performance, allowing the hauler to travel at much higher speeds
for increased productivity. Even when fully loaded, the E-series haulers’
ability to ‘float’ over rough ground without bouncing and
rolling improves operator comfort and safety.
The benefits of full suspension were proven
during extensive field trails carried out using the A35E and A40E models.
Furthermore, these benefits were shown to increase with the length of
the haul road, effectively absorbing all rough spots and allowing operators
to maintain considerably higher average speeds – with or without
a load. Volvo CE says it is now possible for a hauler to travel at 55
km/h over rough roads with minimal bouncing, rolling and shaking.
The full suspension system provides automatic
leveling and stability control on all wheel and instead of the traditional
rubber suspension, there is a hydraulic cylinder fitted to each wheel.
The system constantly monitors the load and ground conditions, adapting
the suspension to suit the prevailing conditions.
Volvo CE says it continues to offer all
E-series models with upgraded versions of the standard suspension system.
The seven models in the new E-series cover capacities from the 24-tonne
A25E to the 39-tonne A40E. All feature Tier 3/Stage 111A-approved Volvo
diesel engines that offer high torque at low revs, high fuel efficiency
and reduced noise levels. Both power and torque have been increased
in the Volvo designed and built D16 engines fitted to the A40E and A40E
FS with a 12 per cent increase in power to 476 hp and 19 per cent increase
in torque. The biggest output increases are found on the D12 engines
used by the A35E and A35E FS, which generate the equivalent power and
torque of the outgoing larger A40D model.
The A35E, A35E FS, A40E and A40E FS all
feature a new fully automatic nine-speed fast adaptive transmission.
Shafts, planetary gears and bearings are all reinforced to cope with
higher torque produced by their bigger engines. An optimized gear shifting
pattern has better overlap of ratios to give constant power transfer.
These models also have new frames, axles and a new drop box with longitudinal
differential and 100 per cent lock up which reduces power losses, improves
traction and provides better fuel economy.
These larger models are fitted with more
powerful exhaust brakes and retarders. In addition, the cooling system
has been improved to the extent that there is no need to fit further
cooling for hot climates.
The A35E now comes with wet disc brakes
for improved stopping power and longer service life. The A40E has a
larger body that has been designed to allow easier loading and a high
dumping joint and long overhang allows the hauler to dump into hoppers
or over an edge.
www.volvo.com
Terex
Terex
upgrades ADT range
Terex has beefed up its new Generation
7 line of articulated dump trucks by adding the TA35 and TA40, its two
biggest models of ADTs. One of the main features of the range-topping
duo is an all new operator’s cab that will be adopted by the smaller
models in the Generation 7 range.
This new, centrally-mounted cab replaces
the side-mounted operator station that was previously used on the TA35
and TA40. The cab has a completely new automotive style dash, with a
Siemens VDO flat screen information panel at its centre. The screen
is flanked by two large clear dials for travel speed and engine revs,
with smaller dials for oil temperatures situated below.
The ergonomic design of the TA cab puts
all of the controls literally at the driver’s fingertips, with
retarder, gear selection lever and handbrake in a curved grouping to
the right of the driver’s seat.
Both the TA35 and the TA40 are powered
by Detroit Diesel 60 series engines. The electronically-controlled 14-litre
Detroit engine meets EPA Tier 3 emissions standards, while providing
similar levels of performance to the previous TA35 and TA40 trucks.
In the TA35 that equates to 400 hp and 2,000 Nm of torque, while the
TA40 has 450 hp available, along with 2,100 Nm of torque.
The biggest change to the driveline
comes behind the engine however, where Terex has moved away from the
remote-mounted ZF310 transmission, in favour of an Allison HD4560. This
transmission is now mounted directly to the engine, enabling Terex engineers
to fit a remote two-speed transfer box after the transmission, effectively
doubling the number of gear ratios available to the operator.
Top speed of the TA40 is 60 km/h in the
upper range, with sixth gear equal to 37.5 km/h in the lower range.
The TA35 has a top speed in the high range of 53.9 km/h.
The manufacturer states that operator
will experience far smoother gear shifting, both up and down the gearbox,
and the transmission offers increased reliability due to the strength
of its construction. To back up its claim, Terex now offers a 10,000
hour/three-year warranty on the driveline.
A greater benefit to the operator is improved
retardation, both from the new oil-cooled service brakes and from an
integral retarder working on the output shaft of the transmission. In
addition, the Detroit engine is equipped with an equally effective engine
or ‘Jake’ brake, which closes the valves and in effect makes
the engine work like a compressor, providing additional retardation.
Unlike the previous TA40 and TA35, both of these retardation systems
can be used separately or in conjunction with each other. The operator
simply switches the engine brake and the retarder on, with switches
on the dash, and then every time their foot comes off the accelerator
pedal the two braking systems come into play.
The retarder has six positions, controlled
by a lever to the right of the steering wheel. The engine brake has
three positions, working on two, four or all six cylinders, controlled
through the switch to the left of the steering. When used together,
the engine brake and the retarder will virtually bring the truck to
a halt, even fully laden on the steepest descents, prolonging service
brake life and reducing operating costs.
The front axle of the TA35 and TA40 has
been moved further back on the chassis, now riding on a four-point suspension
system. This suspension has revolutionised the ride in the cab, and
prevents any dipping of the cab to the side when the steering is fully
turned.
The trucks are permanent six wheel drive
with a differential between each axle to prevent wind-up. All three
axles have automatic limited slip differentials and the leading rear
axle has a drive-through differential which, along with the dropbox
output differential can be locked using a single switch on the dash.
The all-welded high grade steel body remains
virtually unchanged from the successful predecessors, offering a heaped
capacity of 21 m3 on the TA35 and a class-leading 23.3 m3 on the
TA40. Maximum payload is 38 tonnes on the TA40 and 34 tonnes on the
TA35.
www.terex.com
Case
Case introduces two new artic
models
The new Case 327B and 330B articulated
trucks feature more horsepower, an ergonomically designed cab and a
variety of service and maintenance features. These two Tier 3-certified
trucks also feature the same industry-leading technology as the rest
of the Case 300 Series ADT line, such as an integrated differential,
variable geometry turbocharger, auto warm-up system and self-diagnosed
fluid-level checks.
“With the 327B and 330B models in
the ADT lineup, Case customers have a complete range of innovative trucks
to match their demanding applications,” said David Wolf, marketing
manager for Case Construction Equipment.
According to the manufacturer, the Tier
3-certified, electronically controlled Case 10-litre engines provide
greater performance, efficiency and reduced emissions. The four-stroke,
turbocharged, air-to-air cooled diesel engines utilize unit injectors
that increase the pressure of fuel entering each cylinder, above and
beyond the pressure coming off the common rail. The engines also feature
a Variable Geometry Turbocharger (VGT) that provides an optimized air-to-fuel
mixture for peak performance to move more material per hour.
“The engines on the Case 327B and
330B ADTs are more fuel efficient and are fully serviceable and under
warranty through the Case dealer network,” Wolf said.
The fully adjustable, ergonomically designed
operator environment provides excellent comfort and visibility for increased
productivity. Machine operation is made easy with a choice of automatic
or manual modes.
Mounted directly under the center of the
cab, the front driveline is equipped with a new front suspension system
to absorb shocks from rough terrain and provide a more comfortable ride.
“The new front driveline features an integrated transmission-mounted
differential that transfers power directly from the transmission to
the front wheel ends,” Wolf said. “This eliminates a drive
shaft and increases tractive effort to the front wheels, while reducing
noise and vibration for greater operator comfort.”
In addition to the long, sloping hood
design that offers superior forward visibility, the 327B and 330B also
feature a floor-to-ceiling glass cab door, providing more visibility
to the side. The upper window in the new glass door opens for ventilation
while controlling dust entry into the cab.
“At Case, we emphasize ease of service
and maintenance across all our product lines, so the operator spends
more time on production,” Wolf said. “Along with the Case
exclusive swing-out fenders and flip-forward hood, we have added a tilt
cab that gives service technicians outstanding accessibility to the
drivelines, transmission, hydraulic valves and lines, so preventative
maintenance checks are completed with minimal effort.”
Maintenance checks are performed at ground
level, with fluid sight glasses and access panels mounted on the hood.
An automatic lubrication system continuously greases all lubrication
points from a central distribution block.
The 327B and 330B models retain the wide
frame and low dump body, which differentiates Case Articulated Dump
Trucks from the competition. The wider bottom of the bed provides a
lower center of gravity and exceptional stability. This design provides
room for the dump cylinders to be housed inside the frame, which protects
them from the elements better than cylinders mounted outside the frame.
www.casece.com
Caterpillar
Second, smaller Cat ejector truck has
C11 engine
The most recent addition to Caterpillar’s
range of articulated dump trucks is 730 Ejector ADT. It is the second
in the manufacturer’s line to use a self-cleaning ejector mechanism
that allows material to be spread and dumped on-the-go, without raising
the body. Because its body is not raised, the Ejector Truck is designed
to work efficiently on sites where stability issues or overhead obstacles
limit the use of conventional dump trucks. The ejector body also offers
clean load ejection to eliminate material carry-back.
Rated at 28.1 tonnes payload, the 730
Ejector Truck is powered by a Cat C11 diesel engine with ACERT Technology
that meets EPA Tier 3 and EU Stage IIIa exhaust emissions regulations.
The engine produces net power of 317 and features mechanically actuated
electronic unit injection, air-to-air aftercooling and single wastegate
turbocharging.
The engine is matched to a six-speed electronically
controlled transmission featuring an anti-hunt strategy and electronic
clutch pressure control and controlled throttle shifting for smooth
shifts and extended component life. The integral retarder offers high
power density. Its compact design provides more retarding power and
fast response times.
The 730 Ejector incorporates all the features
of the standard 730’s suspension and cab. The proven three-point
front suspension provides a smooth ride to enable the operator to drive
at productive speeds over rough terrain. The inter-axle and cross-axle
differential locking systems with “on-the-go” capability
provide full driveline locking for maximum performance in adverse conditions.
The center-mounted cab and rear-mounted cooling system help provide
excellent sight lines from the operator’s seat.
The load ejection concept delivers many
benefits. Material can be spread while the truck is moving to cut cycle
time, decrease power train loads and reduce the amount of support equipment
needed for spreading and dozing. The ejector also prevents material
from adhering to the inside of the truck body after the dump, so payload
can be maximized, improving productivity, reducing fuel consumption
and lowering cost per ton. Ejecting a load without raising the body
increases stability, so the truck can work on inclines, side slopes
and in very soft underfoot.
The reinforced ejector body is made from
high-yield, heat-treated steel. Its top rails incorporate the same steel
used on the Cat 769D off-highway truck. The ejector mechanism includes
a high-strength blade and technology similar to that proven on Cat wheel
tractor-scrapers. The ejector body is designed to work in applications
where diameter of rocks does not exceed 152 mm.
To reduce downtime, increase availability
and lower costs, the 730 Ejector offers extended engine and hydraulic
oil change intervals, extended life coolant and adjustment-free wheel
bearings. Lubrication points are grouped for convenience, as are service
points under the hood.
www.cat.com
Moxy
Moxy unveils worlds' largest
ADT
Moxy Engineering, a Norwegian-based manufacturer
of six-wheel drive articulated dump trucks, has announced the launch
of its fifth and largest model, the MT51. Due to go into production
in the second half of this year, the 510-hp hauler, with a heaped payload
capacity of 28.8 m3, is claimed to be the largest of its kind in the
world. The manufacturer says the new model takes the best of the current
range of Moxy ADT’s, including traction from the gear-drive, free-swinging
tandem rear suspension system, power from the 15-litre, 6 cylinder Cummins
QSX15 water-cooled Tier 3 diesel engine and reliability from over 30
years of ADT design experience. The MT51 claims a class-leading power
to weight ratio of 6.48 hp per tonne.
The MT51 features a new low-vibration
and low-noise cab design and fully independent front nitrogen suspension
that significantly improves operator comfort. The truck is equipped
with an Alison 4600 ORS automatic transmission with lock up in all gears.
It also has a remote propshaft-driven two-speed dropbox. The all-hydraulic
braking system consists of a dual-circuit acting on all six wheels.
The hauler is fitted with standard 29.5 R25 two star radial tires
The unique advantages of Moxy’s
permanent 6-wheel drive, free-swinging rear tandem bogie, articulation
hinge system, independent front wheel suspension system and sloping
rear frame design are said to provide excellent driving stability with
equal power and weight distribution to the wheels. The Moxy truck is
designed to work in rough terrain while travelling at speeds of up to
50 km/h.
Some of the other key features of the new MT51 are increased stability,
eradicating the need for wide, low profile tires, improved safety due
to better visibility achieved with the new cab and hood design and easier
servicing thanks to centralized remote-mounted service points that can
be reached from ground level. The hood opens to 83 degrees for better
access and an automatic central lubrication system is standard on all
Moxy models.
Cabs are equipped with air conditions
and an air suspension seat. The “tip-tronic” gearshift feature
enables the operator to run the truck in both automatic and manual gear
to ensure smooth gear shifts and momentum.
www.moxytrucks.com
John
Deere
New ADTs deliver productivity gains
John Deere’s 250D, 300D, 350D and
400D articulated dump trucks have been redesigned to increase productivity
and uptime, including updates to the transmission, operator station
improvements, electrical enhancements and a new engine in the 250D and
300D.
“All of the new enhancements boost
the productivity of our ADTs while keeping the overall operating cost
low,” said Chris Maifield, product marketing manager, John Deere
Construction & Forestry Company. “With a significant weight
advantage and the best payload-to-weight ratio among the top five ADT
manufacturers, Deere trucks continue to burn less fuel, particularly
in high time-on-grade applications and in poor underfoot conditions.”
The 350D and 400D are powered by a turbocharged
and inter-cooled Mercedes Benz OM501LA, 12-litre V6 engine that has
been updated to meet Tier 3 EPA emissions standards. Its compact V6
design is claimed to allow the Deere truck to achieve best-in-class
approach angle, and the robust retarding system works seamlessly with
the transmission retarder to prolong service brake life.
The 250D and 300D feature a Tier 3-certified
John Deere 6090 PowerTech Plus I6 engine with 24 valve cylinder head.
Engine displacement has increased from 8.1 to 9-litres. Fuel economy
testing in the 9-litre class shows that this engine provides superior
fuel economy across the operating range.
The transmission has been updated in all
four models to further improve reliability and operator comfort. The
transmission controller features improved shift quality and clutch control.
The 250D and 300D cooling system also provides greater transmission
cooling capacity.
Like the previous models, automatic retarding
on all four trucks offers ease of operation, capacity and smoothness.
Cab comforts include a fully adjustable air suspension seat, more extensive
sound-insulation and a high-capacity air conditioner. A new monitor
provides increased diagnostic capability, and a new sealed switch module
with centralized controls eliminates several rocker switches, a retarder
lever and mechanical HVAC controls.
A relocated electrical center provides
easy access to fuses, relays, and controllers. A new electrohydraulic
tip control enables several functions that make operation easier and
more comfortable. The operator now can set maximum dump body tip height,
and enable either soft or hard stops and the end of dump body travel.
The driveline assist feature automates some of the repetitive actions
during dump body tip. It shifts the transmission to neutral, applies
the park brake and takes the engine to maximum speed when the dump body
lever is in the full dump position. Once the maximum dump angle is reached,
the engine returns to low idle travel.
www.johndeere.com
Komatsu
Updated hauler designed for bigger payloads
Komatsu Canada Ltd. (KCL) recently introduced
its new HM400-2 articulated dump truck. Designed and built for a variety
of conditions from rough terrain construction sites to landfills, the
HM400-2 builds on Komatsu’s exclusive proven features such as
hydropneumatic front and rear suspension, 2-stage lift cylinders, reliable
wet multiple disc brake retarder and maintenance free oscillating hitch.
Komatsu’s new articulated dump truck
features a powerful, clean SAA6D140E-5 turbocharged, after-cooled diesel
engine that provides an increase in the maximum net output to 438 hp.
The new engine meets both EPA Tier 3 and EU Stage IIIA emission regulations.
The environmentally-friendly machine has reduced ambient noise levels
and lead free radiators. The easy-to-load body has a heaped capacity
of 22.3 m3 and a low loading height of 2.97 m.
The HM400-2 is equipped with the latest
Komtrax™ technology which sends machine operating information
to a secure website utilizing wireless technology. Hour meter, location,
cautions and maintenance alerts are relayed to the web application for
analysis. The Komtrax fleet monitoring system increases machine availability,
reduces the risk of machine theft, allows for remote diagnosis by the
distributor, and provides a wealth of other information to drive business
efficiency and productivity.
The new hauler features the Komatsu designed
electronically controlled countershaft transmission with K-ATOMiCS,
which has been proven in Komatsu’s rigid dump trucks. This system
assures smooth shifts without shock and maximizes powertrain life. The
electronic clutch modulation system ensures proper clutch pressure when
the clutch is engaged, and the total control system controls both the
engine and transmission by monitoring the vehicle conditions. The engine
power mode selection system makes it easy to select the appropriate
mode depending on the working condition: power mode for job sites where
the truck meets high resistance and economy mode for light work on the
flat ground. Provisions for tailgates is standard for faster and more
cost effective means of attaching tailgates in the field.
The HM400-2 has a wide cab with electrically
operated windows for better visibility and improved production and safety.
The ergonomically designed operator’s compartment makes it easy
and comfortable for the operator to access all controls. An integrated
cab and floor provide an airtight cab and reduce noise. The cab now
includes two front under view mirrors and four rear view mirrors as
well as an electric heated rear window to facilitate defrosting.
www.komatsu.ca
Back
to top
B.C.
aggregate producer settles pond fines issue
A British Columbia aggregate
producer has developed a unique solution to the treatment of wash plant
process water.
By Andy Bateman, Engineering
Editor
Allard
Contractors is an independent sand and gravel producer, based some 30
km southeast of downtown Vancouver in Coquitlam. The operation there
produces a full range of aggregates, including washed aggregates for
the company’s ready mix concrete operations. To deal with the
familiar issue of settling pond fines, Allard’s unique water treatment
system utilises flocculants to rapidly settle suspended fines out of
grey wash plant process water. Known as floc-sand, the collected fines
soon dry into a manageable cake suitable for pit rehabilitation and
an experimental revegetation program.
For co-owner Jim Allard, the new system represents
a major step forward in fines management and the closely related issue
of pit water management. Allard explains: “Effective water management
is a particularly sensitive issue here due to the proximity of the Coquitlam
River. Over the years, our water management system has evolved to meet
multiple needs, including a reliable supply of fresh water for aggregate
washing, settlement of wash water and containment of surface run off.
“Our goal is to ensure that water discharging
into the river is clean and in normal operating conditions the pit does
not contribute to any sediment entering the river. However, the pit’s
water system can become overtaxed during severe storm conditions, because
storm water from the Westwood Plateau residential subdivision is diverted
into the gravel pits.”
Allard’s original water management system
consists of three fresh water ponds and four settling ponds together
with associated pumps, pipe work and culverts. From time to time, fines
accumulating in the settling ponds are excavated into one of three separate
silt ponds and allowed to dry. There, after a drying period of up to
six months, the fines are transferred to the pit as rehabilitation fill,
although the transfer is still a messy process due to the sloppy nature
of the material.
Once in the pit, another year may go by before the
fill is sufficiently stable to bear the weight of mobile equipment.
For Allard, the promise of improved fill quality as well as improved
water clarification were reason enough to invest significant time and
money in a new approach.
With the “Allard Secret Floc System”,
grey water from the aggregate washing processes is piped near to a new
flocculent house for treatment. A solution of flocculent A is first
added to the process water followed by a solution of flocculent B further
downstream. The flocculent house contains two dilution assemblies such
that a controlled amount of each flocculent concentrate can be mixed
with a controlled amount of clean water. To achieve this, the flow rates
of clean water and flocculent concentrate are controlled by pressure
regulators and a number of check valves to ensure that fluids flow through
the mixing system in the right direction. Each dilution assembly receives
clean source pond water via a 25 mm diameter pipe with the freshwater
initially passing through a Watts pressure regulator set at 45psi +/-
5psi. Once its pressure is regulated, the freshwater flows through as
pressure shut off valve installed in the line as a precaution to activate
if the pressure exceeds 45 psi.
Downstream of the shut off valve, a solenoid switch
regulates freshwater flow and is followed by a spring check valve to
prevent backflow or loss of flocculent concentrate. Downstream of this
check valve, concentrate is introduced into the line, with the concentrate
supply pipe also containing a check valve to prevent flow of clean water
up into the flocculent tote.
Once the flocculent concentrate is in the freshwater
line, the mixture flows through a 25 mm USA BlueBook mixing chamber
to produce a homogenous mixture containing 0.5 per cent flocculent,
that is, 5ml of flocculent per litre of solution. The mixture is fed
into a large tank for storing or pumping into the 102 mm process water
line. Inside each concentrate tote, the level of concentrate is monitored
by a float switch to ensure an adequate supply of concentrate is maintained.
Once diluted, the flocculent solutions are injected into the pit process
water at two locations, with each injection point equipped with a lever
valve for manually regulating flocculent flow if required. Flocculent
A is injected just outside the flocculent house while flocculent B is
injected just before discharge.
Following the addition of the flocculent solutions,
a three outlet manifold discharges the treated water into a rectangular
18.3 m x 4.6 m x 1.5 m floc-sand pond. Three sides of this pond are
constructed with removable concrete stac-a-bloc units while the remaining
end wall consists of a removable steel gate. Within the pond, the floc-sand
precipitates out almost immediately as 10-12 mm diameter pellets and
accumulates on the bottom. At the same time, clear water is allowed
to weir over the steel retaining wall and rejoin the pit’s existing
water system. Each morning, the pond’s steel retaining wall is
removed and the floc-sand is hauled to a nearby floc storage pond.
Some 200 tonnes of floc-sand is generated daily during
the production of 2000 tonnes of washed aggregates, of which about 800
tonnes is concrete sand. On average, the system treats 4500 l/min of
grey water during aggregate washing operations.
From Allard’s perspective, the new system
delivers a number benefits, tangible and intangible, with intangibles
such as the public’s perception of the aggregate industry perhaps
the more important: “This new approach to fines management is
an effective way of demonstrating our environmental commitment to the
general public and other sectors of the aggregate industry. We have
also taken the process a step further by using a mixture of the recovered
fines and biosolids to grow test plots of cottonwood and so provide
a possible method for similar vegetation growth on a larger scale. For
operators, this water treatment method means that collected pond fines
can now be viewed as a potential resource and not just a headache.”
Staying on operations, Allard adds that the floc-sand’s
early stability is a big factor in the system’s success: “Each
day’s accumulation can be dug out of the floc-sand pond by wheel
loader the next morning and within 24 hours the material can be walked
on. Ten days later it is stable enough to support the weight of mobile
equipment.”
These benefits aside, the new system seems to make
good business sense although Allard readily admits it is not cheap to
run. Flocculent A is purchased at $US1.43/lb and Flocculent B is $US1.65/lb,
delivered in 2290-lb totes. At $3000 to $3700 per tote, accurate control
over flocculent mixing and dosage is essential to clarify the grey process
water without using excess flocculent. These flocculent system costs
are equivalent to about $2/tonne of washed sand finished product, so
with other production costs running at about $3/tonne, total finished
product costs of $5/tonne. High as that number may sound, average selling
prices of about $10/tonne for washed concrete sand in the pit’s
market area mean that the process still yields a healthy margin. As
Allard also points out, there are significant cost offsets from reduced
wash pond maintenance and fines rehandling.
Going forward, the focus is on opportunities to drive
down the new system’s operating costs. One such opportunity is
a huge existing stockpile of screened sand containing 20 per cent minus
200 mesh material. Concrete sand produced from this feedstock can be
produced at lower cost as most production costs have already been incurred
in its production. At present, system operating costs are also increased
by the daily requirement to clean out the stac-a-bloc pond, resulting
in some 90 minutes of plant downtime as well as $225 in loader operating
costs. Over 250 annual working days, these additional costs amount to
$56,250 in loader operating and maintenance costs and some 375 hours
of plant downtime.
Plans are in hand to refine the system and eliminate
these clean out and downtime costs. Two 3 m x 3 m inverted pyramid hoppers
will be installed within the stac-a-bloc pond to receive the manifold
discharge rather than allowing the discharge to empty directly into
the pond. Clear water overflowing from the hoppers will discharge into
streams and rejoin the existing water system. Meanwhile the floc-sand
settling in the hopper enters 254 mm piping that is gravity fed into
the pond. Once the pond is full of floc-sand, the end steel gate will
be removed and the sand removed. This refinement will improve the sand/
water separation and reduce time spent on pond gate removal, sand removal
and gate replacement.
Allard Contractors Limited is a family owned business
with five gravel pits, three processing plants, and two ready mix concrete
plants located in Vancouver’s Lower Mainland region.
Back to
top
Bauma
2007 shatters all records
By Robert L. Consedine, Editor
Perfect
weather, huge crowds and the largest array of construction machinery
ever assembled on the planet combined to make Bauma 2007 a memorable
event for everyone who attended. Already recognized as the world’s
biggest construction exposition, Bauma 2007 outdid itself by topping
the 500,000-person attendance mark, an increase of 20 per cent from
the record number of visitors at the last Bauma show in 2004. The proportion
of visitors from outside Germany jumped from 116,000 in the 2004 to
160,000 for this year’s event. According to the show’s organizer,
Messe Meunchen, Munich Airport registered 120,000 arriving passengers
on Thursday April 26th, the midpoint of the show’s seven-day run.
It set a new single day arrivals record for the airport. Bauma officials
report that of the 171 countries represented at the show, the number
of overseas visitors was particularly high from Australia, the United
States, Canada, China, India, Korea, Mexico and Japan. A significant
number also came from the countries in the Arabian Peninsula.
Held at the New Munich Trade Fair Centre, the
show featured 3041 exhibitors, an increase of 7 per cent from the 2004
event, who used 180 000 m2 of space in 16 halls and 360 000 m2 of outdoor
area to present their products and services. Virtually every major manufacturer
of construction equipment and aggregate processing machinery including
Liebherr, who mounted the largest exhibition of equipment at the show,
Volvo CE, JCB, Terex, Caterpillar, Komatsu, Astec Industries, Wirtgen
Group, Atlas Copco, Bomag, Sandvik, CNH Global and Hitachi just to name
a few. Included among the more than 20 Canadian companies exhibiting
at Bauma 2007 were McCloskey International Ltd., Peterborough, Ont.,
Thomas Equipment, Centreville, N.B., Black Cat Blades, Edmonton, Alta.,
Ritchie Bros. Auctioneers, Richmond, B.C., Breaker Technology, Thornbury,
Ont., CME Blasting, Oakville, Ont., Valley Blades, Waterloo Ont., Metaris,
Toronto, Ont. and Camoplast, Sherbrooke, Que.
One of the major developments that occurred
during Bauma 2007 was the acquisition of Fintec Crushing and Screening
Ltd., headquartered in Northern Ireland, and the UK-based Extec Screens
& Crushers Ltd. by Sandvik Mining and Construction. The two companies
are leaders in the design and manufacture of mobile crushing and screening
systems.
“These acquisitions are in line with Sandvik’s
long-term strategy of continued profitable growth and our air is to
become the leading supplier of mobile crushing and screening solutions
to the market,” says Lars Josefsson, president of Sandvik Mining
and Construction. “Extec and Fintec have modern manufacturing
facilities, are strong in R&D and have well-developed distribution
networks. This in combination with Sandvik’s global resources
will make it possible to grow our crushing and screening business into
new markets and service our customers even better,” stated Josefsson.
Sandvik expects the acquisitions to be completed
sometime during the second quarter of 2007.
A survey of exhibitors by show officials indicated
most felt this was the most successful Baulma of all time. “For
Caterpillar and our dealer, Zeppelin, Bauma 2007 was a tremendous success”
stated Colin Treaford, events manager, Caterpillar Inc., Peoria, Illinois.
“We were also able to welcome a record number of retailers and
customers at our stand. The business climate at the fair was very positive.”
Kevin L. Curtis, president and CEO of Besser
Co., a major manufacturer of ready-mix plants and other concrete production
machinery based in Alpena, Michigan, said: “For us Bauma is the
perfect venue at which to exhibit our new machines and develop and strengthen
our relationships within the sector. Since 1989, Bauma has been one
of the main components in our global marketing plan, and we already
have high hopes for Bauma 2010.”
Back to
top
Terex
“King of the Dirt” demo days challenge operators
By Andy Bateman, Engineering
Editor
Multiple
“King of the Dirt” demo days events in 2006, March and April
2007 gave attendees from across North America the opportunity to see
and operate current models in the Terex construction equipment line-up.
Hosted by Terex Construction Americas, these events attracted no less
than 1000 dealers, customers, operators and media representatives in
total. After an opening display of the current Terex tractor loader
backhoe line-up, equipment operators at each event were challenged to
complete a number of skill tests with the Terex TX760B tractor loader
backhoe including “beat the buzzer”, “basketball”,
“softball”, “tire over post” and “steering”.
Attendees also had the opportunity to test operate the TX 860B, TX870B
and TX970B backhoes. The extensive range of equipment available for
testing also included a number of compact machines as well as the TA
40 articulated dump truck, TXL 300-2 wheel loader, TR70 rigid truck
and TS 14G scraper for those interested in the heavier end of the Terex
mobile construction equipment range. Additional attractions to an already
full agenda included a shotgun ride in a NASCAR stock car at Memphis
Motorsports Park, the event venue, as well as Memphis’ famous
Peabody Hotel and Beale Street, “Home of the Blues and birthplace
of rock n’ roll.”
Back to
top
May-June
2007 issue
Aggregates
and Roadbuilding Magazine
4999 St Catherine Street West.
Suite 315
Westmount, Quebec H3Z 1T3
Tel: (514) 487-9868 Fax: (514) 487-9276
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