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Canada's “Rock to Road” Magazine
March-April
2007 Issue
For a copy of the issue
that contains these articles with colour photos, click
here.
Asphalt
show - a hit with visitors
The World of Asphalt 2007 Show and Conference was held March 19-22,
2007 in Atlanta, Georgia at the Georgia International Convention Center.
According to show organizers, the show was a success with both attendees
and exhibitors.
More than 3,600 asphalt, highway maintenance and traffic safety industry
professionals attended the event, with almost 14 per cent international
attendance. Some 222 exhibitors used 6247 m2 net square feet of exhibit
space to display the latest equipment, technologies, products and services.
World of Asphalt featured more educational
programming than ever before, and offered a wider array of products
and suppliers on the show floor.
The 2007 show’s expanded education
included worker certification courses for traffic control technicians
and OSHA construction safety as well as a “hot topics” program
on the very latest in asphalt industry trends. The show also hosted
two of the industry’s leading conferences, the People, Plants
and Paving Training Program and the Asphalt Pavement Alliance’s
(APA) Asphalt Pavement Conference. More than 4,000 tickets were sold
for all of the World of Asphalt learning programs.
New exhibit pavilions in 2007 highlighted
traffic safety products and information technology resources, and joined
testing equipment and “new product” pavilions, providing
additional opportunities for attendees to compare and discuss product
advances and capabilities with leading industry suppliers.
“This was one of our best shows
ever in terms of numbers and most importantly, quality, with an energetic
buzz throughout the show,” noted World of Asphalt Chairman Richard
Moore, President of Lehman-Roberts Co., Memphis, Tennessee. “We
continued our momentum as a showcase for the latest education and technology
innovations in our industry.”
World of Asphalt 2007 concluded with a
well-received continuing-education tour of the renowned National Center
for Asphalt Technology (NCAT), which was another value-added learning
opportunity for show participants.
World of Asphalt 2007 international attendees
came from more than 50 countries worldwide and from all major world
regions. The show had the support of more than 20 U.S., Canadian and
worldwide trade associations as well as leading U.S. state and federal
government agencies. The next World of Asphalt will be held March 9-12,
2009 in Orlando, Florida. The event is held annually except in years
when the CONEXPO-CON/AGG exhibition is staged.
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Roadbuilder
uses technology to control bulk materials
Advanced
site positioning and grade control technology is helping a roadbuilding
contractor accurately measure bulk materials, control grade to tight
tolerances and manage site operations.
By Andy Bateman, Engineering
Editor
Triggered
by rapidly increasing traffic volumes on a popular route between Toronto
and Ottawa, Ontario Ministry of Transportation (MTO) contract 2006-4015
will improve the intersection of Highways 7 and 417 as well as nearby
stretches of both highways. From the contractor’s perspective,
one of the important characteristics of this job is the large volume
of imported fill materials required due to a significant shortfall between
the volumes of suitable site excavation material and design fill volumes.
Well over a million tonnes of imported
earth and rock fill for bridge abutments and earth embankments will
be supplied by third parties, so accurate measurement of these large
quantities is essential for payments to suppliers, job progress tracking
and submissions to the owner for work done. Tomlinson’s GPS-based
site positioning system has facilitated such measurements and more.
Rod-mounted rover units are used to check the elevation and location
of virtually any desired point, while an integral grade control system
guides earthmoving and road base placement operations. Other elements
of the system include a base station, site controller software, hand
held controller, data manager and report utility.
Tomlinson’s Andrew Piasetzki explains
that the $48,063,825 contract is scheduled for completion by June 27,
2008 after a July 2006 start. The section of Highway 7 from 1.8 km west
of Jinkinson Rd to 0.9 km east of Carp Rd is being widened from two
lanes to four, with service roads also being added to both north and
south sides for a total of six additional lanes. Improvements on Highway
417 extend from 1.9 km east of the Carp Rd interchange to 0.1 km east
of Richardson Rd, for an overall contract length of 5.06 km.
In all, the job calls for 479 859 m3 of
earth borrow as well as 164 856 m3 (about 369 000 tonnes) of select
subgrade material (SSM), despite an estimated 282 879 m3 of earth excavation.
In addition, there is about 124 000 m3 of rock embankment compared to
total rock excavation quantities of 88 243 m3, thereby necessitating
some 35 000 m3 of rock borrow.
Piasetzki adds that specifications for
earth borrow require the material to be homogenous and non-plastic (not
containing clay minerals). Fortunately, there are several nearby sources,
including 281 000 m3 from Clark Quarry and 75 000 to 100 000 m3 from
Huntley Quarry, both Aecon Group operations, as well as Tomlinson’s
own Jinkinson Quarry and the Goulbourn Quarry of Thomas Cavanagh Construction
Ltd.
For Tomlinson general manager Bert Hendriks,
one of the most useful aspects of the system has been the initial volume
measurement of large borrow stockpiles and the subsequent tracking of
borrow volumes used on the job. Hendriks adds that it is simpler in
most cases to measure a borrow pile in situ rather than after it has
been placed, when the road widths, ditches, intersections and all other
dimensions have to be measured. According to Hendriks, the volume of
one large borrow stockpile was measured in an hour compared to two or
three days by traditional means.
For contractors, another important aspect
of the system is its ability to determine as built quantities as distinct
from design quantities. This means reduced risk, as payment is based
of actual work done rather than tender estimates. In this regard, the
ability to accurately measure as built bulk excavation and fill quantities
before, during and after construction is analogous to measuring rock
quantities by face profiling. Virtually all excavation and fill materials
have been measured using the system including earth, rock, SSM and even
muskeg (peat bog).
Turning to machine control, the Trimble
GSC900 grade control system uses GPS to provide grade control for Caterpillar
D6R XL and D8T dozers, as well as a Caterpillar 163H motor grader and
330D excavator. The blade of each machine is fitted with two receivers
set a known distance apart, with that information used by the system
to set the blade angle at the design slope (crossfall) angle of, for
example, two per cent. At the same time, tight level control is maintained
in real time with signals received at a rate of four times per second
at the blade. As a further refinement, there is an allowance for compaction,
with the target grade level set slightly higher than the finished level.
The receivers on the dozers differ from
those on the grader to reflect the grading accuracy required. Each dozer
is fitted with two MS990 smart GPS antennas, described as integrated
GPS receiver and antenna units specifically designed for machine installation
in the harsh construction environment. The dual antenna configuration
is (according to Trimble) unique to the manufacturer’s GPS based
grade control systems and enables the exact position, cross slope and
heading of the blade or bucket to be measured. Said to be suitable for
a wide range of machines, the MS990 antenna for GCS900 provides blade
control to within a reported 20-30 mm.
For blade control on the 163H grader,
Tomlinson’s system utilises both GPS and laser technology to provide
improved vertical accuracy. The grader is fitted with a SR300 laser
receiver, working with a GL722 laser transmitter. Together, the GCS900
grade control system, laser receiver and laser transmitter provide grader
blade control within a reported 3-6 mm.
Trimble’s SCS900 site controller
software is a key component of the overall control system and, on this
particular site, runs on a TSC2 hand held controller. Developed specifically
for construction applications, the site controller software facilitates
site measurement tasks such as initial site measurements as well as
periodic measurements to determine progress, material stockpile or as
built–quantities. During construction, the software also assists
in stakeout tasks such as the establishment of points, lines, alignments,
planes and surfaces.
Data transfer between office and field
crew is managed automatically by the SCS data manager and captures all
measurement and stakeout operations for multiple crews and locations.
This data transfer allows office supervisors to organise new site information,
create new work orders and assign them to field crews.
What is GPS?
Global
Positioning System (GPS) is a satellite positioning system designed
and operated by the U.S. Department of Defense. GPS satellites
broadcast radio signals with their position, precise timing
and other information to GPS receivers on the ground. Each GPS
receiver then uses the radio signals from several satellites
to compute its exact location in three dimensions.
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All
devices can be kept current with the latest data, with this data easily
transferable to the controller for field operations. Another piece of
the system, the SCS report utility, allows office supervisors to review
data from a work order and automatically generate report files for any
field operation by crew, site, priority, work status and due date. Consolidated
data can be used for a number of purposes including overall progress
reporting and the submission of as-built quantities.
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Capital
Paving takes Ontario Paver of the Year Award
Excellence
in provincial roadbuilding is recognised annually by the Ontario Ministry
of Transportation (MTO) Paver of the Year Awards. The 2006 awards were
presented at the 80th convention of the Ontario Road Builders Association,
held February 5-7, 2007 at the Fairmont Royal York Hotel in Toronto.
In a change from previous years, the 2006 awards consisted of Paver
of the Year and three finalists.
By Andy Bateman, Engineering
Editor
Capital
Paving Inc. won the prestigious 2006 Paver of the Year Award for work
completed on Highway 403 in Mississauga, including one of the province’s
first High Occupancy Vehicle (HOV) lanes. MTO Contract 2003-2012 extended
from east of Highway 407, easterly to 0.3 km west of Highway 401. Capital
was paving subcontractor to the Bot Construction Group on this 15.1
km long project, with mainline paving beginning in August 2004 and completed
in August 2006. Asphalt paving included multiple lifts on the new eastbound
and westbound HOV Lanes utilising SP25, SP19 and SP12.5 FC2 Superpave
mixes, the resurfacing of existing Highway 403 lanes with SP19 and SP
12.5 FC2 lifts, as well as the resurfacing of all interchange ramps
with SP12.5 FC2 mix.
The job’s location on a heavily
trafficked 400 series highway in the Greater Toronto Area inevitably
meant numerous operating constraints for the paving operation. All work
was scheduled for completion at night due to high daytime traffic volumes,
with lane closure restrictions in the east bound lanes allowed from
10:00 pm to 4:00 am and in the west bound lanes from 11:00 pm to 5:00
am. In practice, these six-hour windows at night provided about four
hours of actual paving time, with the remaining time consumed by strict
lane closure procedures, milling of joints, tack coat, paving, line
marking and lane reopening.
All traffic control was under the direction
of the general contractor, with standard nighttime paving procedures
adopted. As scheduling was also completed through Bot, constant communication
was vital for a successful project. A further additional challenge was
the distance from the asphalt plant to the jobsite, some 45 km, to ensure
“just in time deliveries” as well as a large surcharge of
material at the jobsite for the start of paving.
Access to the new HOV lanes became increasingly
restricted due to the combination of new centre median wall, ongoing
bridge rehabilitation and a temporary concrete barrier (TCB), with the
result that trucks delivering asphalt had no choice but to reverse long
distances back to the paving operation. Cool weather impacted on paving,
as contract conditions required temperatures of at least 2°C and
rising for the SP25 and SP19 mixes and 12°C and rising for the SP12.5FC2
mix. The job was also Capital’s first Superpave job and so required
rapid adjustment by all involved to the (then) new mixes. The SP25 mix,
for example, was found to be susceptible to segregation and required
extra care and attention during manufacturing, transportation and placement.
On site, it was also found that mixes containing 70-28 performance grade
asphalt cement were sometimes susceptible to “pick up” by
the rubber tire rollers.
The team that successfully met all these
challenges included Jim Karageorgos, asphalt operations manager; Mark
Latyn, quality control manager; John Viveiros, asphalt foreman; Jim
Lindhorst and Andre Lavergne, asphalt plant operators; Rodney Alderdice,
assistant site manager and Terry McNeil, quality control technician.
Equipment that facilitated a successful project
included the company’s stationary CMI STD400 triple drum plant
rated at 360 tonnes/h, located at Highways 6 and 401 near Aberfoyle.
Asphalt from the plant was delivered to site by live–bottom trucks
with payload capacities of 35–40 tonnes. At the job site, Capital’s
paving train included a Roadtec SB-2500C Shuttle Buggy feeding a Roadtec
RP-190 paver equipped with a 10-20 hydraulic screed, MOBA electronic
grade package, non-contacting ski, fully-automated feed package, electric
screed heater and custom/in-house lighting package. Behind the paver,
a Caterpillar CB-534D low-amplitude, high-frequency double drum compactor
made two passes, followed by a Caterpillar PS-360B pneumatic roller,
ballasted to 17 tonnes and making six passes. Mat finishing was completed
by a Caterpillar CB-534D making one pass. This compaction trio achieved
average density of 94 per cent.
In addition to the main paving fleet,
Capital kept a full set of standby equipment on site in case of breakdown,
including a Barber-Greene BG-260 paver, a Caterpillar CB-634B double
drum compactor and Dynapac CP21 pneumatic roller.
Overall, a successful project is attributed
to personnel involved in the project from supervisory staff right through
to the labourers and operators running the equipment. Everyone shared
the same goal and worked together to accomplish the project.
On the supply side, equipment was relatively
new and well maintained, while superior quality and consistency of raw
materials from Dufferin Aggregates aided a good result. A well-maintained
and operated asphalt plant was an important factor, as well as excellent
communication between plant and field crews. Best paving practices were
followed by all members of the team, while well designed job mix formulas
were produced by Trow Associates Inc., CTA Lab, and John Emery Geotechnical
Engineering Ltd.
Last word goes to Capital president Geoffrey
Stephens: “Although Capital Paving is not the biggest construction
company in the industry, we are a growing family-owned company and we
tackle some of the biggest jobs in Ontario. The fact that Capital Paving
is the first company to win Paver of the Year twice is an honour and
a testament of the outstanding quality and dedication of our team of
employees. Our commitment to quality is embedded in our paving practices,
but also in all aspects of the company.”
Aecon Construction & Materials received
a finalist award for its high quality work on MTO contract 2006-3036.
This contract on busy Highway 19 was valued at $5.7 million and ran
from July to October 2006. Highway 19 is a direct route from Highway
3 Tillsonburg to Highway 401 and consequently carries a high ratio of
truck traffic. Aecon’s work extended from 0.30 km north of rural
route 18, Mount Elgin, northerly to 0.4 km north of Highway 401, with
the scope of work including grading, drainage, granular base and hot
mix paving, together with concrete culvert extension and rehabilitation
work.
From the contractor’s perspective, the
weather and traffic were the two main factors influencing progress on
this job. Weather conditions were unfavourable to say the least, with
all four months of the project experiencing precipitation above the
30-year average and two months had nearly double the average. Things
were much better on the traffic side, thanks to effective work by traffic
control personnel (TCP). As the contract had approximately five work
zones at any given time, communication from adjacent TCP was paramount
to keep traffic flowing and keep the operation moving safely and efficiently.
As always, site safety was a top priority and reinforced through weekly
tool box talks carried out with every crew on the job site. Aecon’s
award winning team included senior paving superintendent Glenn Pye,
paving supervisor Jeff Pye, senior superintendent Gary Kmith, project
superintendent Danny DiBenidetto and project estimator John Krasko.
Senior contracts manager Brian Morris
reports that the success of this project was very much a team effort
and everyone involved should be commended. A special mention also goes
to Danny DiBenidetto who “put in countless hours in order to achieve
the ultimate goal. Danny has earned the respect of all his peers, and
the local residents along the corridor and is to be commended for his
hard work and dedication.”
On site, operations kicked off with the
in-place processing of the existing road base, with subcontractor Roto-Mill
Services Ltd. utilizing two pulverisers in tandem to accelerate the
process. Hot mix asphalt for the job was supplied by a 360 tonnes/h
capacity portable Gencor counterflow drum mix plant set up in the Beachville
Quarry of Carmeuse Lime. From there, asphalt was hauled to site by triaxle
and flow-boy trucks with payloads of 21 and 38 tonnes, respectively.
On site, the paving train included a Roadtec SB-2500C Shuttle Buggy
and Caterpillar AP-1000D paver equipped with a new electric screed.
Breakdown compaction was completed by a Caterpillar CB-634D double drum
vibratory unit followed by a Caterpillar PS-300B pneumatic roller in
the secondary position. The mat was finished by a Dresser 714 static
machine. The job required some 25 000 tonnes of Superpave SP19 mix,
with coarse and fine aggregates supplied by Oxford Sand & Gravel
together with RAP from Highway 19. In addition, some 11 000 tonnes of
Superpave 12.5 mm FC2 utilised coarse and fine aggregates from Ontario
Trap Rock. Asphalt cement for both mixes was supplied by McAsphalt Industries,
while Oxford Sand & Gravel also supplied 25 000 tonnes of Granular
A and 15 000 tonnes of Granular B base material.
Lafarge Paving and Construction (Eastern)
Ltd. was another recipient of a finalist award for its performance on
MTO contract 2006-4049. This 9.8 km long contract on the eastbound and
westbound lanes of Highway 417 extended from Nicholas Ave to Woodroffe
Ave. in Ottawa. Valued at $4.52 million the contract was completed in
just ten weeks from August 3 to October 13, 2006.
Project superintendent Rick Seguin reports
that the scope of work included paving (paid by the square metre), crack
repair, manhole adjustments, partial depth asphalt removal and barrier
wall placement. Weather and traffic played their part in this contract
as well, with one of the wettest Octobers on record impacting the paving
schedule.
High traffic volumes through Ottawa also
meant that all work was done at night at this location. Seguin adds
that, in an effort to reduce traffic speed, the Ontario Provincial Police
(O.P.P.) was employed to remain within the construction zone. Several
fines were issued for speeding as well as two for entering the work
area. The O.P.P also assisted in the contract’s live traffic switch-overs,
with the nightly switch-over of traffic control executed without a complete
tear down. Weather and traffic aside, the site team also successfully
dealt with night paving under poor lighting conditions, restrictive
time restraints as specified in the contract, numerous catch basins
throughout the majority of lane one, smoothness specifications applied
to the contract and 14 bridge decks in about five kilometres. In addition,
contract conditions required full width paving to the same station each
night, resulting in shorter distances being paved each night and an
increase in the number of transverse joints that had to be constructed.
Seguin attributes a successful project
to the full commitment from the entire team before the project began,
underlining excellent communication between the crews, quality control
staff and contract administration. Key site staff included Brad Gooderham
who was responsible for quality control and asphalt foreman Dave Alve.
Every night before start up, tailgate meetings were conducted to review
safety issues, quality concerns and production goals. A positive working
relationship was established with the contract administration with everyone
striving together to provide a safe work site and deliver a quality
product.
Turning to material and methods, hot mix asphalt
for the contract was supplied from the Boyce Quarry on Rideau Rd., Ottawa,
home to a stationary CMI batch plant with a capacity of 300 tonnes/h.
The milling equipment used by subcontractor Roto-Mill Services Ltd.
included a Terex PR800-7 with a 2.14m cutting width, while the Lafarge
paving fleet included a Roadtec SB -2500C Shuttle Buggy and a Barber-Greene
BG-240B paver. The compaction train included a Bomag BW164AD breakdown
compactor, a Caterpillar PS-300B pneumatic secondary compactor and a
Ferguson 712 finishing roller. Job quantities and materials included
27 106 tonnes of SP12.5 mm FC2 Level E mix using PG 70-28 asphalt cement
from Lafarge Asphalt Engineering’s Millhaven terminal. The Lafarge
group’s Boyce quarry supplied DFC fine aggregate and HL-1 coarse
aggregate, while IKO supplied asphalt sand.
Fowler Construction Company Ltd. also
received a finalist award for its performance on a 10.7 km long section
of Highway 141 between Rosseau and Bent River in Muskoka. This secondary
highway intersects with Highway 11 north of Bracebridge and winds west
to Parry Sound. Company vice president Tom O’Callaghan reports
that the $7.5 million highway reconstruction contract called for the
replacement of 19 centreline culverts as well as 46 000 m3 of rock excavation
to widen the right of way. One section of the contract required company
forces to construct a granite wall to serve as the new “shore
line” of Lake Rosseau and also support a guide rail.
Ironically, given the local availability of granite, the unique dimensional
granite stone used for the wall was imported to Muskoka from
Vermilion Bay, west of Dryden. Additional work included the full depth
reclamation of the existing pavement followed on the majority of the
roadway by just 50 mm of Granular A base and a single lift of SP12.5
asphalt. Time was tight, as the highway had to be pulverized and paved
in 15 days. Asphalt from the company’s stationary plant in Bracebridge
was paved by the site team utilising a Roadtec SB -2500 shuttle buggy
and Caterpillar AP-1055B paver, followed by a Bomag BW174AD compactor
equipped with Asphalt Manager and a Bomag BW24R rubber tired roller
to finish the mat. O’Callaghan adds that Fowler received a bonus
for smoothness, also noting that approximately two kilometres of the
highway was exempt from asphalt smoothness measurements due to the tight
radius of some curves.
“What was quite unique was that
we were able to achieve an excellent smoothness index, with only one
lift of asphalt on granular grade. Both the grading and paving
crews are to be commended in their efforts to achieve smoothness.”
Fowler’s team included Gilles Truchon,
manager of construction; Tim Fawcett, divisional manager of MTO Projects;
Doug Buchanan, project superintendent and Roger Brassard, paving
superintendent. In O’Callaghan’s view, the success of this
contract is a good example of teamwork in action:” Doug Buchanan’s
team would have provided the smooth grade for Roger Brassard’s
team, responsible to utilize Fowler’s “Best Practices”
for paving. Collectively those two have over 70 years of experience
in highway construction.”
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What's
new in portable crushers
Metso
New generation of Lokotracks launched
Building
on more than 20 years of experience with the Lokotrack mobile crushing
concept, Metso Minerals recently announced an entirely new generation
of mobile plants for primary crushing. The Lokotrack LT3054, LT1315
and LT1415 combine continuous high crushing capacity, a broad range
of process options and user-friendly operation with the latest dust
and noise reduction options.
The new generation Lokotracks are designed
for both high capacity contract crushing and the severe service quarrying
and in-pit crushing applications. Due to the low transport height, the
units can be easily transported on a standard trailer. When equipped
with the optional over band magnetic separator and pan feeder below
the crusher, trouble-free processing of recycled materials containing
rebar is possible.
With a capacity range of up to 900 tonnes/h,
the new Lokotrack models are an excellent choice for any single- or
multi-stage primary and secondary crushing process. They have operating
weights from 54 to 63.5 tonnes, and are powered by an environmentally
friendly Tier 3 Caterpillar diesel engines.
During the past 20 years, the original
Lokotrack product line has expanded to more than 30 different models
with over 3,000 units delivered world wide.
The new Lokotracks are built around the
field-proven Nordberg C Series jaw crushers and NP Series impact crushers.
The C Series crushers are designed for cost-efficient primary reduction
of hard and abrasive materials. They are based on modular, non-welded
frame construction offering the highest possible fatigue strength.
The NP Series impact crushers are capable
of crushing medium hard rock types, such as limestone, as well as all
rock-based recycled materials. The NP crushers feature a large feed
opening to avoid bridging, a unique triple-wedge hammer retention system
for simple and quick locking of wedges, and heavy-duty construction
for a long and reliable service life.
To meet specific application requirements,
the new Lokotracks can be equipped with several feeder options: a high
capacity grizzly (LT3054), a pan feeder/scalper (LT3054, LT1315, LT1415)
or a roller grizzly (LT3054, LT1315, LT1415) capable of handling highly
viscous feed materials.
Both new Lokotrack models can be equipped
with the optional, highly efficient two-deck screen and product conveyors.
This enables production of one or two calibrated end products. When
equipped with the circulation conveyor, the screen oversize fractions
can be returned to the crusher.
Other key features include the new IC700
intelligent control system that optimizes the crushing process for improved
performance and product quality, easier operation and enhanced serviceability.
A detachable screen module with two decks that offer the facility for
closed circuit operation and the ability to produce a number of different
end products, is available as an option.
www.metso.com
Telsmith
New portable crushing plant delivers high output
Designed
for high-capacity performance in tough applications, the new Telsmith
3258 portable crushing plant is engineered with features that are claimed
to boost production, reduce maintenance requirements, improve safety
and enhance mobility. The plant travels at 4.1 m high and 3 m in width.
At the heart of the plant is the Telsmith Model 3258 hydraulic jaw crusher
that is equipped with a 812 mm gape and a 1473 mm wide crushing chamber.
According to the manufacturer, the unique, finger-tip controlled, hydraulic
adjustment cylinders reduce maintenance and increase uptime production
while the hydraulic overload system automatically protects the crusher
from tramp metal.
The crusher is fed with a 1524 mm wide
and 6.1 m long vibrating grizzly. For optimum portability, the grizzly
feeder, loading hopper and grizzly bypass chute comprise one modular
unit. The entire module can be removed as one piece, sliding off the
back of the plant and simplifying travel in weight restricted travel
areas. Additionally, the chassis is equipped with a standard tri-axle
air ride suspension. An optional 4th axle can be pneumatically elevated
off the ground, reducing wear and tear during tight onsite maneuvering.
The 3258 portable plant offers a variety
of standard and optional features to increase its versatility, and ease
of operation and maintenance.
Capable of either diesel or electric power,
these plants feature an optional variable speed drive for the feeder.
Diesel plants incorporate a 365-hp engine with a hydraulically activated
trans-fluid clutch. Push-button controls engage the clutch automatically,
and a hydraulic belt tensioner is used to maintain a constant belt pressure,
eliminating the need to adjust belts. Several leveling systems are available
as options. Using an innovative approach, Telsmith has tucked the cylinders
under the plant, allowing extra room around the support legs for blocking.
Large service platforms are built into the chassis for easy access to
the jaw, feeder and engine.
www.telsmith.com
Fintec
Heavy-duty jaw crusher provides onsite mobility
The
Fintec 1107 is a track-mounted primary jaw crusher system designed and
built for tough quarry duty, yet is fully transportable on a low-boy
trailer, making it suitable for producers with multiple aggregate sites.
Track-mounted plants are becoming more
popular in aggregate applications because their mobility allows the
crushing and screening system to follow the quarry face, reducing trucking
costs.
Manufactured by Fintec Crushing and Screening
Ltd., the 1107 features the latest crushing technology, including finite
element techniques to minimize stress levels within the frame itself.
With a throughput of up to 362 tonnes/h, the plant utilizes a heavy-duty
1100 mm x 700 mm Sandvik J11 jaw crusher that features the unique ability
to interchange the fixed and swing jaw.
The single-toggle, hydraulic wedge-adjust
crusher incorporates a symmetrical crushing chamber with an equal nominal
and effective feed opening. A deflector plate at the top of the moving
jaw allows all of the feed opening to be active – crushing the
material from the very top of the chamber – and eliminates the
need for a stationary cross wall in the feed area, which can reduce
true feed allowance. The result is a feed opening that accepts large
feed material – which can often cause bridging and jaw plugging
with a conventional opening – without the need for an additional
breaker system. An optimized nip angle ensures that material progresses
smoothly down the crushing chamber for high reduction, productivity
and even utilization of the jaw plates.
The Sandvik jaw also features a lubrication-free
toggle plate and reversible jaw dies. Clamping bars that fix the jaw
plate to the crusher are easy to install, and with the support bars,
are easily replaceable, reducing total life-cycle costs for the crusher.
A heavy-duty frame is constructed with
two side plates of rolled steel and hollow casting at the front frame
end and moving jaw to provide high strength- and rigidity-to-weight
ratios. The uniformly welded frame provides equal strength in all directions
for durability against shock loads, and minimizes the risk of main-frame
failure that can occur with bolted-on construction.
The 1107 is also equipped with a Sandvik
heavy-duty feeder and a 3-ply extra heavy duty main conveyor. The standard
weight is 43.5 tonnes, which makes it transportable on a low-bed trailer.
Onsite mobility is achieved by simple
controls, sturdy 508 mm wide tracks and a Caterpillar Tier III-compliant
engine.
www.fintec.com
Extec
Track-mounted cone crusher boosts productivity
The
new X44 SBS cone crusher from Extec Screens & Crushers Ltd. has
been designed from the ground up to enhance production and profitability
Some of the new features built into the
X44 SBS mobile crushing plant include: a hydraulic drive-CAT C-13 diesel
engine; variable speed, high torgue for controlled continuous feed;
a feed hopper, mounted on hydraulically controlled slew ring, that decreases
down time after metal detection in in-feed material and, hydraulic closed
side setting adjustment
The cone unit is a Telsmith 44SBS complete
with a hydraulic closed side setting adjustment, which allows the X44
SBS unit to be set to produce a range of products from 10 to 45 mm.
The X44 SBS throughput depends on whether the unit is used in a closed
or open circuit set up. A rate of 410 tonnes/h can be achieved with
the coarsest setting in an open circuit.
The hydraulic closed side setting adjustment
has been developed to enable crusher setting changes to be made quickly
and easily. The adjustment is activated through the control box, making
this system particularly suitable for applications where regular cone
setting adjustments are required.
The X44 SBS utilises a Caterpillar C-13
diesel engine to provide the power for the hydraulic power pack, and
to generate electricity for the electrical systems of the machine. The
tracks, feeder, cone, conveyors and all other working parts of the machine
are hydraulically driven.
A number of features on the X44 SBS are
designed to improve productivity and enhance maintenance procedures.
For example, the feed conveyor includes a metal detector as standard
equipment. If any metal is detected in the feed material, the belt swivels
through 30 degrees and discharges a half conveyor load to the side of
the machine. This stops any scrap or other metal objects falling into
the crusher and damaging it. Another feature of the machine is that
the X44 SBS possesses an intelligent control system. This allows Extec
machines to communicate with each other during the same operation: so
if an Extec C-12+ jaw crusher is feeding the X44 SBS, and there is a
blockage in either machine, it will stop.
Additional features available on the X44
SBS include heavy duty Hardox steel hopper liners for prolonged active
life; a recirculating screen box for a guaranteed finished top size,
and an optional bogie for quick and easy transportation in between job
sites.
www.extecscreens.com
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Recycling
contractor keeps pace with increased demand
A Richmond, B.C.-based
recycling contractor has added portable aggregate processing capacity
to keep pace with increasing demand.
By Andy Bateman, Engineering
Editor
Privately
owned Richvan Holdings Ltd. began recycling concrete and asphalt at
its River Road site in the late 1990’s A decade later, the company’s
growth reflects a thriving provincial economy and a sharp regional increase
in demand for virgin and recycled aggregates. Richvan’s production
totalled 250 000 tonnes in 2006 and is on target for 350 000 tonnes
in 2007. To keep pace with this demand surge, a track-mounted crushing
and screening plant has recently been acquired to boost aggregate production
capacity in a single portable unit.
Owner Leno Gagno reports that a full range
of recycle materials are processed on the 5.26 ha site, including demolition
concrete with and without rebar, reject concrete block, concrete plant
surplus material, broken asphalt and milled asphalt. These feed materials
are typically processed into 75 mm minus, 19 mm washed drain rock and
manufactured sand by the operation’s existing fixed plant, while
the new portable plant focuses on granular base production.
One of the striking operational aspects of this
business is the constantly varying nature, volume and location of feed
material within the operation. In visits separated by only two days,
Aggregates & Roadbuilding saw the portable plant processing very
different types of feed material in separate locations on the same property.
On the first visit, the unit was producing
granular base from slabby, sorted concrete at the back of the yard.
Just 48 hours later, the same unit was working near the front gate,
where a mixed stockpile of predominantly broken asphalt was also being
processed into granular base. These frequent location changes underscore
the value of portable capacity that allows the producer to convert feed
into product without having to haul either around the property. The
same variability in feed, typical of recycle operations, also requires
vigilance on the part of plant operators to ensure that no excessive
oversize, steel or other potentially damaging material enters the unit.
By the same token, the portable plant
itself must be able to deal with concrete and asphalt feeds of different
hardness and size as well as any residual steel in concrete feed. Some
recycle plant operators have learned the hard way that oversize or long
rebar pieces can quickly result in damaged crusher blow bars, linings,
ripped conveyor belts and plug ups if allowed to enter the crusher.
In Richvan’s case, the portable
and fixed plants both appear to be well matched to the application.
The fixed plant utilises the well proven combination of primary jaw
and secondary impactor for crushing. Recycle feed is first reduced by
a Kolberg-Pioneer 31x44 jaw crusher before being conveyed to a JCI 5x16
triple-deck screen for size separation. Oversize is directed to a 4050
impact crusher in closed circuit with the screen, while screened 19
mm drain rock is washed and dewatered by an Eagle Iron Works 610 mm
x 6.71 m single-screw fine material washer.
In typical duty, Richvan’s portable
unit produces 19 mm minus or 75 mm minus granular base material from
mixed concrete and asphalt, with support equipment a function of the
feed type. Where demolition concrete has a significant rebar content,
feed is often first loosened and sorted by a Caterpillar 330C excavator
before being baled out to a Caterpillar 325BL excavator fitted with
Stanley shears. The 325BL separates most of the steel from the concrete
and, in turn, bales concrete pieces to a Caterpillar 345B excavator
feeding the plant. With more forgiving feed such as broken or milled
asphalt, the 345B usually works solo. Acquired in June 2006, the track-mounted
Kolberg-Pioneer Fast Trax FT4240 teams a horizontal shaft impact (HSI)
crusher and 4 x12 double-deck vibrating screen in closed circuit, enabling
raw feed to be directly processed into finished product. Richvan’s
unit is equipped with an optional magnet mounted above the product belt
to remove steel (or other ferrous material) not removed by the pre-sorting
process.
Like many operators of impact crushers,
Richvan has experimented with the metallurgy of the portable HSI crusher’s
blow bars to, as far as possible, maximise bar wear life without breakage.
The trade off here is bar wear life versus impact resistance. Standard
manganese bars have high impact resistance and are more tolerant of
large feed sizes, but also wear relatively quickly.
Alternatively, high chrome bars are harder
and offer increased wear life but are more susceptible to breakage from
oversize or uncrushable feed. In any particular application, the goal
then is to find the hardest bar that will resist chipping or breakage
from the largest or hardest feed material it is likely to see. John
Gagno reports that bars with a chrome content as high as 25 per cent
for concrete or asphalt feed have been delivering good results. That
appears to be about the upper limit, as Gagno started to have breakage
problems with 27 per cent chrome content bars.
According to Kolberg-Pioneer, the portable
plant is designed for rock and recycle applications, well suited
to crushing base material from recycled materials and able to deliver
production rates of up to 295 tonnes/h. Reduction ratios for this single
crushing stage unit are said to range from 12:1 up to 18:1. The vibrating
grizzly feeder provides a 4.27 m long, 4.21 m3 capacity hopper to support
continuous operation with fewer loads.
Manufacturer’s data also indicates
that this HSI crusher utilizes the maximum performance rotor (MPR),
said to offer the integrity of a solid rotor design with the accessibility
of a segmented rotor. Replaceable, bolt-on wear liners and primary and
secondary apron tips are all standard equipment, while hydrostatic drive
with a three bar rotor is optional.
Further options include an under feeder
conveyor, allowing undersized material from the feeder to be transferred
out of the side of the plant and windrowed or stockpiled. In a closed
circuit configuration, the remaining oversize from the screen can be
transferred back to the impact crusher feed opening for further reduction
by means of a closed circuit conveyor system.
If desired, the conveyor receiving material
retained on the screen’s bottom deck can be reversed so that sized
material can be removed as a product to be stockpiled. For applications
requiring movement across public highways, the unit is transportable
on a low-boy trailer with indicated dimensions of 20.21 m overall length
(with screen), 3.38 m overall transport width, 3.48 m overall transport
height and a weight of 44.9 tonnes.
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National
Heavy Equipment Show takes flight
From its relatively modest beginnings in 1997,
the National Heavy Equipment Show (NHES) has taken flight and is now
one of Canada’s principal show events for the construction industry.
At this year’s show, over 11,000 attendees had the opportunity
to see the latest from 231 companies on virtually every aspect of the
equipment business in displays totalling nearly 27 900 m2. The 2007
show was held March 22-23, 2007 at the International Centre, close to
Toronto’s Pearson International Airport and former home to the
De Havilland aircraft manufacturing plant.
In addition to the extensive exhibitor
displays, attendees again had the opportunity to compete in the popular
Backhoe Rodeo, a skill-testing event where contestants run five machines,
with the winner returning the best combined time. This year’s
Rodeo was sponsored by Ontrac Equipment Services Inc. in the Centre’s
Hall 4 and won by Octavio Miranda of Miranda Construction Haulage.
Adding to an already lively atmosphere,
some of the supporting industry associations took the opportunity to
host their own successful functions during the two-day period. These
included the Thursday breakfast of the Canadian Association of Equipment
Distributors (CAED), as well as the Spring Operations Seminar of the
Ontario Hot Mix Producers Association (OHMPA).
The NHES is organized and produced by
Master Promotions Ltd.
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March-April
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
EMail: rocktoroad@sympatico.ca
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