June 2002
Large regional quarries provide a growing proportion of the crushed stone in the United States, but is bigger better?
By Bob Drake
Shipment of stone by water—here, from Vulcan’s Reed Quarry in Kentucky—allows producers to competitively expand markets and quarry operations to take advantage of economies of scale that help lower cost per ton.
A shipload of crushed granite bound for Houston in 1986 boldly signaled the opening of Foster Yeoman’s Glensanda quarry in Scotland. The coastal operation was dubbed a “Superquarry” because of its remote location and its capability of supplying distant markets with more than 5 million metric tons (mt) per year of aggregate. Although at least a half-dozen U.S. quarries had for decades achieved similar feats—but at shorter distances—the trans-Atlantic shipment of Glensanda granite brought worldwide attention to the Superquarry concept.
Foster Yeoman’s stone shipments to the United States didn’t last long. The company today exports about 80 percent of its 6 million-mt/year production to northern Europe. To date, European ownership of U.S. aggregate companies has had a greater impact on U.S. markets than has imported European stone. But the Superquarry concept has taken hold. Large coastal quarries in the Americas are providing increasing amounts of construction aggregates to cities along the East, Gulf and Northwest coasts.
In 1987, Vulcan Materials Co. entered into a partnership with a Mexican construction company to develop a large limestone quarry on Mexico’s Yucatan Peninsula. The joint-venture operation began shipping crushed stone to U.S. Gulf Coast markets in 1990. Vulcan bought out the joint venture for about $121 million early last year, making it the sole owner of the 6,000-acre quarry site, deep-water harbor, two Panamax-class self-unloading ships and U.S. distribution yards.
In 1995, Martin Marietta purchased a coastal granite quarry on Nova Scotia’s Strait of Canso and in 2000 began construction of a new aggregate plant and ship-loading facility at its Freeport, Bahamas quarry. Completed this year, the Bahama Rock operation, which serves East-coast customers from Maryland to Texas, is the largest new-plant investment in Martin Marietta’s history, the company said.
Increased import activity also is evident on the West Coast. Last year, Hanson Aggregates West signed a five-year contract with Canada Steamship Lines (CSL) to haul stone from a Construction Aggregates Ltd. quarry in Sechelt, B.C. (northwest of Vancouver), to San Francisco. A new ship-loading system at Sechelt runs at rates up to 4,600 metric tons per hour (mt/h), CSL reported. Ships unload at Hanson’s San Francisco dock at rates of more than 2,000 mt/h.
In April, Vancouver, B.C.-based Global Industrial Services, an aggregator of industrial mineral, aggregate, engineering, construction and drilling companies, said it received mineral leases and permits to mine 500,000 mt of stone from its Sechelt, B.C., property. The company said it has more than “200 million tons of drill proven dolomite, limestone and granite” and is working with a transportation company to export construction aggregates to the United States. “With the lower Canadian dollar exchange rate with the U.S. dollar, the timing is ideal for the export of Canadian crushed stone,” the company said.
Since 1990, U.S. imports of crushed stone have tripled to about 15 million mt/year, according to the U.S. Geological Survey (Figure 1). But in spite of this impressive growth, imported aggregate—primarily from Mexico, Canada and the Bahamas—amounts to less than 1 percent of the total U.S. consumption of crushed stone.
Figure 1. U.S. Imports of crushed stone
Super quarries abound
Part of the reason imports contribute so little to the U.S. crushed stone market is because of the limited number of water-accessible markets compared to inland markets; and because of the large number of domestic Superquarries already serving large inland markets as well as some coastal areas. In fact, based on a generally accepted production threshold of 5 million mt/year or more, the 19 largest quarries in the United States are of Superquarry size, according to USGS statistics.
Of the 10 largest quarries in the United States identified by the USGS (Table 1), only three ship aggregate by water: Vulcan Materials’ Reed Quarry in Kentucky; Oglebay Norton’s Calcite Quarry; and Lafarge North America’s Stoneport Quarry in Michigan. The other seven depend on rail and truck transport.
Geology played a dominant role in development of many of these Superquarries. In some cases—operations near San Antonio and Miami for example—large quarries exploit the only suitable near-surface stone deposits that are reasonably close to major urban markets, such as Houston, Orlando and the east coast of Florida. Steel companies originally developed the large Michigan coastal quarries to tap deposits of high-calcium limestone and dolomite. Decreased steel manufacturing forced these quarries in most cases to shift primary markets to serve construction aggregate demand around the Great Lakes from Chicago to Buffalo.
Perhaps a more significant trend affecting U.S. aggregate markets is the increase in the number of moderate to large regional quarries. Many of these operations use the same basic concept as a Superquarry—remote location with bulk transport of stone to distribution yards serving many local markets—but most produce less than 5 million mt/year.
The growth of regional quarries is driven in part by the increasing difficulty of obtaining permits for new quarries and by the lack of accessible reserves in or near urban areas. In a 1999 interview in Geotimes magazine, Brian Fowler, an engineering geologist with 30 years experience in the heavy construction and aggregate industries and principal of North American Reserve, discussed what he called the “supply proximity” problem in the Northeast. “In the next 10 to 20 years, our aggregate supplies will be fresh material produced from regional megaquarries at costs that will be substantially higher than those we enjoy today,” Fowler said.
In the last two decades, the number of quarries in the United States producing 1 million mt/year or more almost tripled, from 171 in 1980 to 477 in 2000, according to the USGS (Figure 2). In 1980, these quarries produced about 32 percent of the total crushed stone consumed in the country. In 2000, quarries of million-tons-plus capacity produced more than 50 percent of the nation’s crushed stone. There were more than 3,500 active quarries in the United States in 2000.
| Figure 2. number of U.S. Quarries producing 1 million MT/Y |
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Regional megaquarries can provide significant benefits to producers, such as access to expanded market areas. In a recent annual report, Martin Marietta stated, “The company believes that its ability to transport materials by ocean vessels and river barges and its increased access to rail transportation…has enhanced the company’s ability to compete in certain extended areas.”
In 1994, Martin Marietta shipped 93 percent of its aggregate by truck and 7 percent by rail. Following acquisition of Redland Stone in Texas, Meridian Aggregates, the Nova Scotia and Bahamas quarries and two large quarries on the Ohio/Mississippi River system, the company reported that last year it shipped only 77 percent of its aggregate by truck, 15 percent by rail and 8 percent by water.
Rinker Materials’ FEC Quarry near Miami shipped more than 11.5 million mt last year. All of it was moved by rail and truck, according to Cliff Kirkmyer, vice president of Rinker’s quarry division. Rinker operates a Transport Group that manages arrangements with about 500 truck owner-operators.
“A broader distribution network can provide for a higher degree of success,” said Kirkmyer, who spent 7-1/2 years managing distribution of stone from Vulcan’s Mexican quarry before joining Rinker in 1996.
Logistics play an important role in bulk transport operations, such as ensuring sufficient inventory to load ships on schedule.
Transport logistics
The benefits an operator of a regional quarry gains from expanded access to markets are complicated, however, by some inherent logistical problems. “It’s a seven-day-a-week, 24-hour-a-day operation,” said Kirkmyer about Rinker’s FEC Quarry. “You need to have a hard and fast schedule for all activities, from the pit to loadout. We run two operations shifts and one maintenance shift each day. Keys to success are communications between shifts and departments—what needs to be done when—and a strong support structure, including maintenance, purchasing and administration.”
Tom Hayes, applications specialist for Caterpillar, agreed that mine planning and maintenance are key. “A good mine plan allows operations to know just what will be mined and when. This plan is the basis of how the quarry became a Superquarry,” he said. “Maintenance is the other 50 percent of the equation. If the maintenance falls off, machines are not capable of maintaining scheduled up time, which results in lower production.”
And lower production can lead to reduced product inventory, which is critical when relying on bulk-transport systems for distribution. As it is, the logistics of transporting stone to customers by rail or water adds a level of uncertainty to the business. Martin Marietta noted its increased exposure to railroad performance, “including track congestion, crew availability, and power failures, and the ability to renegotiate favorable railroad shipping contracts.” A water distribution network has similar uncertainties, Martin Marietta said, “including the ability to negotiate favorable shipping contracts, demurrage costs and barge or ship availability.”
Fowler also recognized the limitations of railroads in solving the “supply proximity” problem. “Heavy regulation, limited track networks and lack of terminal facilities prevent them from becoming a more easily available solution,” he said.
Martin Marietta reported that although its increased reliance on rail and water transport provides opportunities for increased revenue and total profit, freight costs have eroded margins. “This typically occurs where the company transports aggregates from a production location to a distribution location by rail or water, and the customer pays a selling price that includes a freight component,” Martin Marietta said. “Margins are negatively affected because the customer typically does not pay the company a profit associated with the transportation component of the selling price.”
Some aggregate companies attempt to limit the risk of transportation uncertainties by owning or exerting significant control over freight operations. Control of the transportation system and distribution network is a significant advantage, according to Kirkmyer. “Without control, you could not manage inventory or meet market demands,” he said.
Foster Yeoman leased two ships and bought a third to service its Glensanda Superquarry. The company also formed a joint venture with Hanson in the United Kingdom to operate Mendip Rail Ltd., which transports more than 5 million mt/year of crushed stone from the companies’ inland quarries.
In the United States, Vulcan Materials owns two ships that haul aggregate from its Mexican quarry to Gulf Coast ports. Oglebay Norton, an owner and operator of Great Lakes vessels prior to its entry into the aggregate industry, has a fleet of 12 self-unloading ships that service its three large coastal quarries in Michigan. In 2001, the company combined its Michigan Limestone Operations with its marine services business to create a Great Lakes Minerals segment. Approximately 75 percent of the limestone transported by the company’s marine fleet comes from its three quarries.
“The combination of Michigan Limestone with the existing marine transportation capabilities established the company as the largest and only fully integrated producer and bulk transporter of limestone on the Great Lakes,” Oglebay Norton reported. “The company can now mine, process and transport stone to the company’s own docks or directly to customers on a delivered cost per ton basis…with an efficiency that non-integrated competitors cannot match.”
In addition, early this year, the company agreed to pool its fleet operations with American Steamship Co.’s 11 Great Lakes vessels in order to deploy the fleet more efficiently and provide better service to its shipping and limestone customers, according to Oglebay Norton.
Economies of scale
Do large quarry operations always provide crushed stone to customers at a lower cost per ton? “Typically, yes,” said Kirkmyer, “You can spread costs over more tons.” He qualified his answer, however, by noting that large operations usually buy larger, more expensive equipment. And large quarries require more support staff with more senior people who have more experience, according to Kirkmyer.
Highly skilled and experienced employees with a good working knowledge of the equipment they operate is a characteristic of large operations also recognized by Paul Smith, product manager for JCI. “Larger producers also tend to be extremely sophisticated in terms of tracking their maintenance and operation costs,” Smith said. “At high production volumes, even the smallest savings to the cost per ton can [add] thousands of dollars to bottom line profits.”
Automation is a key factor used today in large quarries to maximize production volumes while minimizing plant downtime and cost per ton, Smith said. “Cost reduction is the driving incentive to implement systems and procedures that improve economies of scale.”
Getting to that point, however, can be difficult. Large, complex aggregate plant projects seem prone to cost overruns and delayed start ups.
“In some cases, a producer’s increased revenues or reduced labor costs might initially be offset by increased capital expenses or transitional learning curves associated with implementing [automated] systems,” Smith said. “However, producers striving to improve their economies of scale often benefit through reducing indirect or hidden costs as well. For example, in addition to improved efficiencies and flexibility within the operation, larger producers typically also operate in a safer manner that reduces their exposure to worker’s comp and insurance liabilities associated with injuries.
“Aggregate processing has long been considered as much an art as a science,” Smith said. “Today, through use of advanced technology, larger producers have the ability to produce exactly what they need, almost by the push of a button.”
In many ways, bigger is better, but not without significant risks and challenges. Traditional crushed stone facilities that serve a 50-mile radius around the quarry thrive or languish in part based on their proximity to local construction projects. Superquarries, on the other hand, often must develop, maintain and reliably supply multiple markets hundreds of miles away. For those operators, logistics can make or break the business as much as location.
Bob Drake is editor-at-large for AggMan.
Large regional quarries provide a growing proportion of the crushed stone in the United States, but is bigger better?
By Bill Welgoss
Bigger, stronger, faster have been the trends with each year’s new models of wheel loaders and hydraulic excavators. But, lately that has only been the beginning. Add to that
ergonomic cabs, safety and health advancements and computer technology—to ease repetitive digging and loading cycles and to provide troubleshooting, maintenance and performance tracking—and today’s digging machines enable new standards to be set in uptime and operator and maintenance efficiency. In short, even under pressure to meet stricter engine emissions and noise standards, manufacturers have advanced performance in their new or upgraded models to allow for more productivity than ever before.
Below is a sampling of the latest technologies developed by manufacturers to boost productivity.
Wheel Loaders
1. Case D Series
Case says it has designed a cooling module for its D Series wheel loaders that helps the machines run quieter and saves money through less component wear, longer fluid life and more uptime.
The cooling system is offered on the Case 521D and 621D wheel loaders and the 521D XT and 621D XT (pictured) tool carriers. Models range from 110 to 130 hp, and can be equipped with 2.0- to 3.0-cu. yd. buckets.
The D Series cooling system uses a Case-exclusive mid-mount, cube-shaped module that supplies clean air and more efficiently cools the engine and components, according to Case. By eliminating stacked coolers, the cooling system design prevents debris from plugging between coolers. This reduces owning and operating costs through less fluid breakdown and lower component wear.
The design also supplies cooler air, because the air no longer gets repeatedly heated while passing through the series of stacked coolers. That means the engine and fluids get the cleanest, coolest air possible from the top and sides of the cube.
Other advancements include a large hydraulically driven fan that runs independent of the engine and an optional reversible fan; a closed-center, load-sensing hydraulic system; and ground level access to all daily maintenance points.
2. Caterpillar 980G Series II
Caterpillar 980G Series II Wheel Loader improvements over the 980G model include an Integrated Braking System, which reduces axle temperatures and improves transmission neutralizer smoothness. The unit is powered by a Cat 3406E engine, which offers electronic unit injection. The Cat ADEM III engine control system offers electronic governing, automatic air-fuel ratio control, injection timing control and system diagnostics. Flywheel power is 311 hp. The engine meets EPA Tier 2 emissions standards. The free wheel stator torque converter improves power train efficiency in situations where ground speed is high and resistance is low. An optional Caterpillar aggregate autodig can be fitted to the unit for efficient bucket loading. Bucket sizes range from 5.0 to 7.5 cu. yds. A pressurized cab keeps dust out and is equipped with a new Caterpillar comfort seat with air suspension.
The 980G II offers ground-level access for routine maintenance. A central lube bank allows remote greasing of most parts requiring such care. For spill-free maintenance, ecology drains equip the engine, transmission and hydraulic oil sumps. Axle oil ecology drains are an option. Another option available is Cat QuickEvac. The new on-board system performs automated engine oil changes and prelubrication of the engine before cranking. Prelubrication and filling of filters before cranking eliminates the need to run the engine before verifying proper oil level, and it reduces engine wear. The cooling system is factory filled with Caterpillar extended life coolant, which can extend change intervals to as long as 6,000 hours.
3. Kawasaki 135ZIV-2
Kawasaki’s 135ZIV-2 wheel loader is the largest and newest addition to its wheel loaders, now consisting of 11 models. The unit can be equipped with a 12.8-cu. yd bucket and matches with 50-75-ton haul trucks. Advancements include an automatic traction control system, which monitors wheel spin and decreases engine rpm in a wheel-slippage condition.
Other items include a fully electronic QST30 Cummins Celect engine with a built-in protection system; a hydraulic system that uses variable piston pumps for both steering and main circuits; a mode control system; a power boost button on the boom lever that allows the operator to increase digging power by 10 percent momentarily; a lock-up clutch in the converter to allow the torque converter to go to direct drive; and K-Lever steering and single-lever hydraulic controls.
An option available for the 135ZIV-2 and other Kawasaki loaders is the K-Link system. This provides a satellite link to assist in monitoring machine location, hours and alarms. From a distant control location, a user can keep track of how the machine is operating and its exact location. Kawasaki says it will also be providing links to the engine and transmission electronic controls to allow the K-Link system to monitor a range of powertrain functions. This system could also be adapted to monitor data from electronic scales and auto lube systems.
4. Komatsu WA450-5/WA480-5 and WA600-3
Komatsu America International Company announced upgrades to its WA450-5 (pictured) and WA480-5 wheel loaders.
According to the company, the 261-hp Komatsu SAA6D125E-3 engine provides optimum combustion of fuel at both low and high speed/power applications. Engine torque has been increased 23 percent in the WA480-5 and 19 percent in the WA450-5. Fuel consumption has been reduced 15 percent. An optional lock-up torque converter saves fuel in load-and-carry and hill-climb operations. Performance items include two engine-operating modes—normal and power. The hydraulic system provides more rim pull when using the transmission kickdown switch. The automatic transmission enables selection of manual shifting or three levels of automatic shifting modes (low, medium and high).
Komatsu has designed the 450/480-5 to include a main monitor—EMMS (equipment management monitoring system), which displays 38 different machine functions. Komatsu builds a loadmeter right into the main monitor. This allows the operator to put the proper amount of material into the truck or hopper. The Komatsu loadmeter displays the loaded bucket weight. The loadmeter does not require the operator to pause the operation of the wheel loader to get the loaded weight reading since the controller calculates the load on the go. Up to five different materials can be tracked by this system, and a printer is also available for the loadmeter to print out the weights.
Komatsu has also recently introduced the WA600-3 wheel loader. It uses all of the Avance Plus characteristics: increased operator comfort and control; enhanced serviceability; improved components and a 450-hp Komatsu engine compliant with Tier 2 emissions regulations. The WA600-3 has a breakout force of 83,477 lbs., and bucket range of 6.7 to 8.0 cu. yds.
Joystick steering is available on many Komatsu loaders. The Komatsu joystick steering option offers a standard steering wheel and a joystick.
5. LBX Link-Belt L130
LBX Company LLC offers a new series of wheel loaders—the L120, L125 and L130 (3.2 cu. yd. bucket capacity, pictured). According to the company, the loaders use Power-Link geometry which gives Link-Belt loaders a higher breakout force compared to traditional Z-bar geometry across the entire lift range.
Loaders use electro-hydraulic servo controls which give the operator finger-tip control. The linkage design allows the operator to maintain a level-lift with forks or bucket with substantial lift forces without sacrificing the high breakout forces needed for earth or aggregate applications, according to LBX.
A lift height limits function, and can be preset. The frame is also designed not to come in contact with a truck’s sidewalls.
Nitrogen accumulators in the lift circuit act as shock absorbers and allow the loader arms and bucket to float over contours for site cleanup. A kick-down button puts the loader into first gear, and automatically goes into second gear when moving from a pile.
Other items include an optional ride control function; a liquid-cooled Cummins engine; ergopower transmission and dual-circuit, fully hydraulic, wet multi-disc brakes; a diagnostic system that constantly monitors all the main control components; and limited-slip differentials standard on both front and rear axles.
6. Volvo E-Series
Volvo Construction Equipment North America, Inc., now offers five models in its E-Series: L120E, L150E, L220E and L330E. Bucket sizes range from 3.0-9.9 cu. meters (L120E) to 6.1-13.5 cu. meters (L330). E-Series engines provide improved horsepower and higher torque at low rpm. Engine output ranges from 224 hp at 1,800 rpm (L120E) to 503 hp at 1,800 rpm (L330E). E-Series loaders are powered by Volvo Tier 2 compliant electronically controlled engines. Other advancements include a load-sensing hydraulic system. Two variable piston pumps provide the exact flow and pressure required, according to Volvo.
A Contronic control and monitoring system is also provided. The system’s three computers monitor operational functions in real time, store data for analysis and allow for reprogramming and updating of the machine’s functions. With the E-Series, Contronic’s control panel continuously relays information about fuel consumption, oil levels, fluid levels and temperatures.
E-Series Models are equipped with the Volvo Care Cab II. Air in the cab is filtered in two steps. According to Volvo, this provides the cleanest cab environment on the market.
A new rounded exterior provides improved visibility around the machine. E-Series loaders also offer improved service hatches and platforms. Other advancements include: enhanced powershift transmission with automatic power shift; frame and three-point engine and transmission mount that reduces vibration and cab noise; and optional low-profile tires.
Hydraulic shovels/Excavators
7. Case CX Series
Case’s CX Series line includes five models with an electronically controlled engine and advanced pro control system (PCS) hydraulics. Industry-first electronically controlled diesel engines, featured in the CX210, CX240, CX290, CX330 and CX800 (pictured), use sophisticated electronic engine controls, high-pressure fuel injection and high-strength components. According to Case, engines have superior power-to-weight ratios in a design that boosts airflow, provides more power, improves response and increases fuel economy. Engines use an electronic governor to more closely control engine speed. The asynchronous control of the electronic governor allows all engine functions to be tuned. Engines use charge-air cooling to lower the temperature of the air entering the combustion unit, reducing engine stress and improving combustion. Electronic fuel injection delivers higher injection pressures and controls timing and fueling to match the load. Engines also offer auto warm-up to get systems on-line quickly and an auto idle feature to conserve fuel. The CX800 unit is rated at 480 gross hp.
An onboard computer selects the optimal operation mode by sensing load demands and automatically balancing power and speed for the greatest efficiency and economy. PCS hydraulics use a swing-priority feature, which monitors and automatically prioritizes oil flow based on demand. The system boosts flow to the swing motor or the arm cylinder when needed.
Auto power boost, available on the CX210 through CX800, instantly increases power by 10 percent in eight-second intervals when the Pro Control System detects resistance.
The speed assistance system uses a double-pump combination for boom lifting, arm open and close, and regenerates hydraulic oil for boom lowering and arm closing. Cushion control ensures a smooth stop, less spillage and greater operator comfort.
A large new backlit liquid-crystal display panel provides more than 11 messages and readouts on operation status. Units also offer an electronic anti-theft system.
8. Caterpillar 5110B
The new Caterpillar 5110B hydraulic excavator establishes a new size class suited for loading 50- to 60-ton-capacity trucks in four passes, and is capable of loading trucks with capacities as large as 100 tons. Mass excavator buckets range from 8.1-13.6 cu. yds. Mass excavator breakout force is 112,725 lbs.
The electronically controlled hydraulic pumps and Caterpillar proportional priority pressure compensating (PPPC) valves prioritize flow based on the operator’s joystick inputs. Electronic underspeed control prevents excessive engine lugging. The hydraulic system also features a separate, variable-capacity temperature-sensing cooling system.
The Cat 3412 hydraulically-actuated, electronically-controlled unit injection (HEUI) twin turbocharged air-to-air after-cooled engine produces 696 net hp at 1,800 rpm. The electronic engine control system senses engine conditions and operator requirements and adjusts the engine for the most efficient operation. The engine communicates with the hydraulics to match hydraulic output to engine power. The engine cooling system uses a seven-core modular radiator, the Caterpillar advanced modular cooling system (AMOCS).
The Electronic Monitoring System II provides three warning levels to alert the operator of impending or current problems. The system also stores performance data that aid diagnostics. Five different service modes help technicians quickly diagnose mechanical and electrical systems.
9. Caterpillar 385B
Caterpillar’s 385B hydraulic excavator is the latest addition to its 300 Series. The 85-metric ton unit is powered by a 513-hp Cat 3456 engine equipped with electronically controlled unit injection. The engine meets worldwide emissions regulations.
Proportional priority pressure compensated hydraulics offer advanced electronic control for power, efficiency and control-ability, according to Cat. The unit can be equipped with a mass excavation boom and 7.25-cu. yd. bucket.
The 385B offers extended service intervals of 500 hours for engine oil and 4,000 hours for hydraulic oil. The Cat electronic technician service tool allows quick diagnosis of excavator parameters, says Caterpillar.
Electronic joystick controls allow the operator to configure the control pattern and responsiveness. The Cat-designed electronic control system uses the vital information display system (VIDS). VIDS includes an analog gauge section, a display screen and a keypad for requesting information and changing displayed information.
Service points are centrally located. A remote greasing block on the boom and grease fitting for the swing bearing deliver grease to hard-to-reach components. Capsule-type hydraulic filters ease replacement and eliminate spillage.
10. Hitachi EX1200-5
Hitachi replaced its Hitachi EX1100 with the EX1200-5 in a new series of excavators. The EX1200-5 matches with 35-40 ton articulated dump trucks and with 40-90 ton rigid frame haul trucks. The size has been increased from the EX1100. The unit weighs 244,800 lbs. in a loading shovel configuration. Loading shovel bucket capacity is 7.7 cu. yds. (rock bucket).
The EX1200-5 uses an in-line six-cylinder turbocharged air intake inter-cooler engine that provides 671 hp at 1,650 rpm. The engine is supported by Hitachi dealers.
The “swing priority” hydraulic system allows for a faster boom-down operation, making it faster to go into the muckpile while loading trucks. A heavy lift circuit increases lifting capability by 10 percent.
The cab has been redesigned, and its size has been increased 10 percent. The EX1200-5 comes with a data logging unit (DLU) which monitors the engine, hydraulic and electrical functions. The information can be downloaded to a laptop computer.
Large doors allow for easy access to the engine and pump compartments. Extended oil and filter change intervals have reduced downtime and cost of servicing the EX1200-5, according to Hitachi.
11 John Deere 600C LC and 800C
John Deere now offers a 57-metric-ton 600C LC and a 75 metric-ton 800C (pictured). The units are driven by charge-air-cooled and turbocharged 15.7 engines rated at 396 SAE net hp and 453 SAE net hp (at 1,800 rpm), respectively. The large-displacement engines are are emissions certified. Fuel economy is boosted with Deere’s Powerwize II engine/hydraulic management system. According to Deere, the system constantly balances hydraulic pressure and flow to improve engine efficiency.
A tungsten-carbide thermal coating on the bucket-to-arm joint increases durability and the greasing interval, according to Deere.
The cab offers an automatic, “blend-air” climate control system. The top of the cab offers a smoke-tinted sunroof hatch.
Daily lube points, filters and dipsticks are in grouped locations. Standard on the 800C is an on-board, electric lubricator for greasing front pins. It can be used to lubricate other equipment on the job, too. The lube unit and auxiliary hose store beneath the steps at the right front of the machine.
The mass-excavating package offered for both models uses a 9-ft., 8 in. arm, available with a 23-ft., 4-in. boom.
12. Komatsu PC750LC-6A
Komatsu’s PC750LC-6A excavator, introduced in December 2001, offers a new Tier 2 compliant engine. The SAA6D140E-3 engine offers 10 hp greater output and decreased fuel consumption, according to the company. The engine is an electronically controlled “common rail injection” unit. The PC750LC-6A uses two PC400LC-6 swing motors to increase swing torque and acceleration. The result is a 4-percent increase in productivity and 1-percent decrease in fuel consumption. The combined features provide 5 percent more output per gallon of fuel consumed, according to Komatsu
Oil and filter intervals (hours) have been extended: engine oil, 250-500 hours; engine oil filter, 250-500 hours; hydraulic oil, 2,000-5,000 hours; and hydraulic oil filter, 250-500 hours.
New DT connectors (sealing deutch style) are used on the wiring harnesses. Also, element-exposed wires are covered in heat resistant casing.
The main frame has been reinforced to improve durability. The swivel joint mount has also been improved. Swing circle bearing capacity has been increased to extend its life. A 3-percent noise reduction was achieved in the cab.
13. LBX Link-Belt 800LX
LBX Company’s new addition to its Link-Belt LX Series, the 800 LX, is available in a standard and mass version bucket rating. Both versions use an Isuzu BB-6WG1XQB engine with 444 hp. The 23-ft. 9-in. boom on the mass model comes with a 9-ft. 9-in. arm and a bucket range of 2.47-5.91 cu. yds.
An Inte-LX computer control system monitors hydraulic output and pressures and regulates engine performance. Auto power-up, a function of the Inte-LX system, automatically supplies a power increase. Hydraulic pressure sensors detect resistance, and pressure is increased by 9 percent for eight seconds. Auto Power-Up always stays on in the lift mode.
Other items include four selectable work modes and Auto-Mode. In Auto-Mode, Inte-LX instantly changes modes ensuring the best combination of speed and power, according to LBX. An on-board diagnostic system analyzes up to 148 items in four categories, and machine history can be downloaded to a personal computer. A self-diagnostic system troubleshoots electrical faults and monitors key excavator functions. Auto power swing is a patent pending design that incorporates a selector valve which helps maintain attachment and swing flows. The Nephron filtration system allows hydraulic fluid to be changed every 5,000 hours. An Easy Maintenance System extends greasing intervals to once every 1,000 hours or six months.
14. Liebherr Quarry Excavators
Liebherr Quarry Excavators range in operating weight from the 78,000-lb. R944, with a bucket range of 1.0-3.4 cu. yds., to the 505,000-lb. R994, with a bucket range of 11.8-19.6 cu. yd. Pictured is the 264,550-lb. R984C, with a bucket range of 3.7-13.1 cu. yds. Breakout force of this unit is 123,680 lbs. Maximum digging depth is 26 ft., 5 in.; maximum reach at grade is 42 ft.; and maximum dump height is 30 ft.
Liebherr’s Litronic operating system has now been incorporated into the complete range of quarry excavators. This operating system is composed of electronic and functional hydraulics that control, regulate, coordinate and monitor all of the key elements of the travel and work functions of Liebherr quarry excavators.
The Litronic system has sensors on the engine, pumps, hydraulic tank and servo circuit that continuously reports operating data to the control and instrument panel.
Automatic protective devices are a part of the Litronic system that can shut down components should a critical condition exist.
By using computerized electronic controls for the main pumps, there is more direct use of available engine horsepower on Liebherr excavators without wasting fuel, according to the company. These electronic controls also avoid excessive energy wastes by keeping oil from being forced through over-pressure relief valves. Another advancement is the independent dedicated swing pump, which the company says allows maximum utilization of available horsepower during swing operation providing faster cycle time.
The operator’s cab is sound insulated, has tinted windows and high visibility for operational areas. The operator’s seat adjusts to the operator’s individual weight with a six-way adjustment available. Joysticks have been integrated into the adjustable seat console. An audio-visual display constantly indicates operating condition of the machine.
15. O&K RH Series
O&K RH Series use the company’s patented TriPower kinematics, which O&K says boosts crowd and digging forces without additional energy consumption. According to O&K, TriPower eases the stress on the excavator, reduces wear and optimizes bucket fill factor. O&K’s front-end attachment is retracted under zero pressure, which accelerates cycle times.
A board control in-cab diagnostic system monitors operating and service data, displaying findings on a monitor. When variances are detected, the operator is alerted visually and audibly.
Excavators are equipped with diesel engines, but are also available with electric motors. A pump managing system with electronic load limit control continuously evaluates engine and hydraulic system operating values against stored set values. It will adjust pump output to improve output, according to the company. The system also optimizes engine power for a given task. Other items include variable oil-flow control, automatic engine idle, zero-flow and output control; and pressure cut-off on the main pumps.
O&K uses a patented cooling system, which is independent of the return circuit. This allows the system to run at optimum operating temperatures under extreme conditions, according to O&K.
O&K units can be configured either as excavators or shovels. Sizes range from the RH30-F (80 to 90 metric tons, with bucket capacity of 6.3 cu. meters (shovel) and 5.1 cu. meters (backhoe) to the RH 400 (920 metric tons, with a 50 cu. meter bucket capacity). Pictured is the RH 40-E, with a 100 metric ton operating weight and a 8.1 cu. meter bucket capacity. According to O&K, the RH 40-E loads a 60 metric ton truck in five passes. It is powered by a Cummins QSK 19-C engine rated at 640 hp, at 1,800 rpm. Units larger than the RH 40-E come equipped with twin engines.
For service backup, direct satellite links between the excavator and a service office are available.
16. Volvo B-series
The new B-series of Volvo excavators are powered by turbocharged Volvo engines. Pictured is the EC330B. According to the company, the horsepower of each Volvo engine is precisely matched to hydraulic system requirements in order to maximize performance, provide high fuel efficiencies and fully comply with EPA Tier 2 and EU Step 2 emission standards.
The new B-series excavators have a hydraulic system designed with four power modes that respond automatically to the operator’s joystick movements and application requirements.
The boom, arm and swing priority systems; boom and arm flow regeneration; and two variable displacement piston pumps are designed to enhance performance. They combine to provide high swing torque and powerful digging forces, with fast digging and swing speeds, according to Volvo.
In the cab, the seat and joystick control consoles can be adjusted independently. The cab is also equipped with an automatic electronic climate control (ECC) system.
Additional cab items include shock-reducing mounts, sound-absorbing material, an additional rear-view mirror, a pressurized cab and ventilation system.
The B-series maintenance systems and tools include: Service Contronic, MATRIS (machine tracking system) and VCADS Pro (Volvo computer aided diagnostic system professional).
For the boom and arm, chromed pins and internal cylinder cushioning are used.
All models in the Volvo B-series are 97 percent recyclable. A hydraulic pressure relief system promotes safer changing of attachments.
Bill Welgoss is senior industry editor for AggMan.
Compression Crushing vs. Impact Crushing
Consider these pros and cons of both crushing types if you’re unsure what’s best for your operation
By Ed Hayes
Sometimes, choosing between using compression crushers or impact crushers for certain applications is clear. For other applications, however, it can be a “judgement call,” as an operator decides among positive and negative factors of each type of crushing.
If impact crushing is chosen, it is critical to analyze the raw-material characteristics very carefully for the immediate mining areas as well as for the long-term mining areas. Doing so ensures that any changes in the abrasiveness and the crushing characteristics of the raw material won’t substantially increase the crushing costs, and thereby, reduce operating profits.
All raw-material characteristics should be considered when choosing between compression crushing and impact crushing. These include the following:
1. Compressive strength (hardness) of the raw material:
• Soft—5,000 to 10,000 psi.
• Medium—10,000 to 20,000 psi.
• Hard—20,000 to 30,000 psi.
• Very Hard—30,000 to 45,000 psi.
• Extremely Hard—Over 45,000 psi.
2. Abrasiveness of the raw material.
3. Thickness of the beds and the laminations of sedimentary-type rock, such as limestone, dolomite and sandstone.
4. Cleavage planes of igneous and metamorphic rock, such as granite, gneiss, quartzite, trap rock, basalt and diabase.
The thickness of the beds, the laminations and the cleavage planes will affect the elongation-of-particle ratio and the cubicity differently depending on whether compression or impact crushers are used.
The reduction ratios for impact crushers can range from 10:1, up to 20:1. The reduction ratios for compression crushers can range from 5:1, up to 7:1. Therefore, in many applications, the crushing of the raw material to the desired finished products can be accomplished using fewer impact crushers instead of more compression crushers. Fewer impact crushers require fewer structures, conveyors and screens as well as resulting in a more compact plant. When used in highly abrasive raw material, however, the wear rates and the resulting operational costs for impact crushers will become substantially higher. In just a matter of months, wear cost and cost of plant downtime will exceed the capital savings compared to using compression crushers.
Important factors for Compression-Crushing
For jaw crushers, the top size of the raw-feed material should not exceed approximately 80 percent of the shorter dimension of the feed opening. Also, the reduction ratio achieved by the closed-side setting should not exceed the crusher manufacturer’s specific recommendation for the reduction ratio, and also for the compressive strength of the rock.
For cone crushers, the proper crushing chamber should be used. The top size of the feed should not exceed approximately 80 percent of the feed opening dimension. The crusher should always be run with a full chamber and with an even non-segregated feed distribution around the entire circumference of the crushing chamber. Also, the closed-side-setting should be within the crusher manufacturer’s recommendation for the specific compressive strength of the rock so as not to incur any “ring-bounce,” structural failures or mechanical failures.
Important factors for Impact-Crushing
It is very important to consider that, for horizontal shaft impactors (HSIs), crushing efficiency is at its maximum only when the blowbars are new with sharp, angular leading edges. This enables the rotor to shear the larger particles and to impart the maximum energy to shatter the smaller particles by hitting a “line-drive.” As the blowbars become increasingly worn and their leading edges become more rounded, the rotor hits more “pop flies” and imparts less energy into the rock. This reduces the product reduction ratio and also causes more “rebounds” within the crushing chamber, which in turn increases the blowbar and apron wear rates. This increased inefficiency also increases the recirculating load back to the HSI or it sends more oversize particles to the next crusher in the circuit.
In vertical shaft impactors it is very important to consider the type of crushing chamber to utilize. The crushing chamber with anvils will usually give a higher reduction ratio with less minus 200-mesh product than the rock-shelf autogenous crushing chamber. The rock-shelf type of chamber saves the replacement cost for worn-out anvils, but usually results in a reduced ratio of reduction and more minus 200-mesh byproduct from inter-particle abrasion.
Since each plant site, raw material characteristics and market product requirements are different, every producer should invest the time and research into determining the right combination of equipment for each new plant and for each modification to an existing plant. The time invested in the detailed research can pay big dividends in customer satisfaction (product quality) as well as corporate profits.
Ed Hayes is the president of H&H Solutions, Inc., in Gettysburg, Pa.
The Berg Corp. Finds Lucrative Niche with Complete Demolition and Recycling Services
The Berg Corp. chose to spend a little bit more money for a tracked mobile crusher to realize savings due to the unit’s ability to work in tough environments.
The first thing that strikes an observer at a demolition job by The Berg Corp. is the color purple. The Baltimore-based demolition and recycling contractor paints all its equipment and signage purple.
“We like to be different. You gotta have an angle on everything,” said David J. Berg, owner of The Berg Corp. “In this business, your best advertisement is your on-site equipment and signage. When people see us, they remember.”
With a 60-person workforce, The Berg Corp. specializes in complete demolition utilizing recycling.
“We are very into material handling. We can go into a building and segregate it into all its basic components,” said Berg.
Last December, the company expanded its crushing operations with the purchase of a Kolberg-Pioneer 2649 Rocky Trax, track-mounted mobile jaw crusher from Baltimore-based McClung-Logan. The Berg Corp. first entered into material crushing in 1990 with a Pegson 2844 wheel-mounted mobile jaw crushing unit.
“We got into crushing because I’m a CPA, so I’m a numbers guy. I saw how much money we were paying for trucks and how much money we were paying to go to the landfills,” said Berg. “I look at a crusher as a mobile landfill.”
Berg bids a job the way the competition bids: he calculates the amount for hauling and dumping debris. The savings realized by crushing debris on-site goes into paying for crushing operations.
“You only have one chance to get the money, and that is when you bid it. Once you bid it, you are locked in, and you have to look at every angle you can to get production, safety and profits,”said Berg.
Though more expensive, Berg went with a track-mounted unit with the purchase of the Rocky Trax. But, the unit pays for itself in material handling savings, according to Berg.
“Do you know how much handling it takes to load out 40,000 cu. yds. of crushed material? When it is not crushed, it is 60-70,000 cu. yds. You have to pick it up, put it into a truck, move it, dump it and handle it again,” said Berg. “We put the track machine by where we tear down. We lift the material one time to feed the crusher, which reduces material volume by a third. When you are moving thousands of yards a year, it saves a lot of money.”
Another asset of the track-mounted machine is that it can go about anywhere. It can travel over an embankment with as high as a 20-percent grade, and it can travel over rebar and other debris that would need to be cleared for rubber-tired units.
Other key equipment The Berg Corp. uses includes seven Komatsu PC-300 excavators. Berg also has two PC-220s and a PC-200. All, of course, are painted Berg Corp. purple. Maintaining a fleet of excavators from one manufacturer allows the company to use its large battery of attachments—buckets, pulverizers, grapples, shears, etc.—on any machine. For screening, The Berg Corp. uses a Powerscreen Turbo Chieftain.
With crushing and screening capabilities, The Berg Corp. is able to win a lot of bids by being able to provide spec product to the builder on-site. This not only saves the builder—in one case about a quarter million dollars—but it also provides substantial savings for The Berg Corp. by reducing the cost of hauling material off-site.
The Berg Corp. also is the only company in the Baltimore/Washington market that carries a fleet of remote-controlled robotic excavators made by Sweden-based Brokk. The company owns two BM-250 units, a BM-150 and plans to buy the recently introduced BM-90 unit.
“These small robotic excavators go inside buildings and take out concrete slabs, stairways, elevator cores—hard stuff made easy. And, they’re indestructible,” said Berg.
Essential to the company’s success, according to Berg, is planning. Operations people meet at 5 a.m. to go over every detail of a job.
“Before we start a job, we go through a budget, labor and equipment. We make a blueprint that shows how we are going to physically do it,” said Berg. “Then we update it on a daily basis. We know the production we are getting, where the material is going—every aspect is considered up-front.”
Scheduling equipment utilization is another major component to the company’s success.
“We know where all the equipment is going, especially the crushers. We have two crushers, and we know where each one is going in the next three months.
“Every piece of equipment has a job board, and I can show you man hours, how many hours it has on it and when maintenance is scheduled,” said Berg. “We work six days a week, so we have to be this way.”
Preventive maintenance is another key. “It is more important than getting the job done, because if you don’t have equipment running, then nothing is getting done,” said Berg.
All equipment owned by The Berg Corp., except for a 1996 excavator, is a 1999 model or newer: “We keep our equipment in excellent shape.”
What attracted Berg specifically to the Rocky Trax unit were a handful of items.
For one, the unit weighs 106,000 lbs., which is simlar to competitive models, but it offers more capacity, according to Berg.
“The 49-in.-wide opening makes a tremendous difference (5 in. longer than the opening on the other crushing unit). You can’t imagine, but we are handling 20 to 25 percent more throughput,” said Berg.
Berg also preferred the dual hydraulic drive over a V-belt drive, and the hydraulic system that allows remote adjustment of the closed-side setting of the crusher.
The company uses a rig and a low-boy, both of which need to have four axles to transport the unit legally in Maryland and Virginia.
Time savings are realized by a feed hopper that does not need to be folded down. In fact, there are no set-up or breakdown procedures for the Rocky Trax. It can be put directly into service.
A capability offered by the Rocky Trax unit that has yet to be utilized by The Berg Corp. is its ability to process virgin aggregate.
Berg said that since December, the Rocky Trax unit has done four jobs, which have accounted for about 40 percent of the unit’s purchase cost in a three-month span.
Bob Drake is editor-at-large for AggMan.
Avoiding the ‘Production at Any Cost’ Mindset
When it comes to hydraulic hammers, production at any cost usually means at a high cost
Editor’s Note: This monthly column is supplied exclusively for AggMan by Association of Equipment Management Professionals (AEMP).
Operator training and realistic production expectations are critical to the successful use of breakers.
When considering the purchase of a breaker to be used in the crushed stone and aggregate industry, it is wise to understand what you are in for. A quarry or mine generally represents the greatest demand placed on a breaker, significantly more than in contracting or construction projects. Therefore, operating cost is a much greater consideration in the crushed stone industry.
Pound for pound, breakers are one of the most expensive pieces of equipment to purchase and maintain in the industry. Many people call them self-destructive. Others say that breakers are remarkably tough, considering the demands placed on them. All say that they are a vital part of their operation and are excellent replacements for drop balls, not to mention their ability to enhance safety by clearing jammed crushers.
Below are common questions asked by aggregate producers and answers supplied by Jim Lafon, vice president and regional sales manager for Tramac Corporation.
Question: Why is weight not a good measure when considering a breaker for my oversize requirement?
Answer: Design features are critical for aggregate producers when selecting a hydraulic breaker. The total breaker weight is important when matching to the carrier. It is a misconception that there is value in weight. Actually, the only important weight in a breaker is the weight of the piston. It is more important to consider production or performance relative to carrier size and carrier weight. Many people assume that the heavier the breaker, the better—but this is a misconception. In reality it is better to choose the lightest breaker capable of matching your project requirements. For example, heavy and large breakers, used in small-jaw crushers, are extremely difficult to place on the rock. Think about it! If you can’t place the tool correctly on the rock, what good is more power? Then choose a carrier that will not only operate the breaker, but also provide other specific duties. A breaker is like any other equipment. It is best to match total performance to meet your expectations.
Question: What about the CIMA Tool Energy Rating? I need a standard that I can rely on to make an intelligent buying decision.
Answer: Performance or production is the result of the proper impact frequency in addition to the CIMA energy rating. It’s useful to compare breakers to engines. Frequency of impact is as important to a breaker’s performance as RPMs and torque are to an engine’s horsepower—without one, you won’t have the other.
Consider competing in the Daytona 500 with a haul truck engine. The haul truck engine has the horsepower, and it certainly can do the work. But it can’t go very fast and is improperly matched to the task. Matching the proper elements of total performance is what really gets the job done. Make sure the breaker impact frequency (impact blows per minute) is properly adjusted.
Next, you should consider the piston shock wave design, which is as important as any other factor. Shock wave design produced by a breaker is as important as the one produced when blasting. When you have considered reliability, operator training, carrier match and breaker design, to name a few, then add CIMA Tool Energy. At that point, you have a more complete measure of performance. There is no one factor more important than another.
Question: What are the most significant problems associated with hydraulic breakers, and how can they be minimized?
Answer: In order to address this question correctly, it is best to choose specific brands and models for comparison purposes. Each has its own unique strength and weakness. I take the position that it is best to ask the manufacturer for operating cost projections and a projected maintenance and repair schedule for each model you are considering. A reasonably good comparison can be made by this method, providing the manufacturers have a population of breakers in the crushed stone industry.
To be specific to the question, the greatest challenge that the end user will face is operator training and basic maintenance. I would suggest that the best precaution against unforeseen maintenance expense is to require that the operator be correctly trained. It’s easy for a manufacturer to claim that high operating expense is due to poor operating technique. Operators who attend training seminars have far fewer failures. Their operating cost is significantly lower than the ones who are untrained. If an operator is trained and skilled at his profession, he can save you the purchase price of the breaker in operating expense.
The basic problem is our culture and the great economy of this country. Many times, we demand production at any cost. What I would like to impress on the breaker owner is how much equipment abuse costs him. If the cost of abuse is understood and the owner can justify it, at least it can be accounted for in his overall business cost. No one likes surprises. Premature failure caused by untrained personnel and neglect due to poor maintenance have become a common part of the industry. If production is expected at any cost, that is exactly what you will get!
Question: Is there a difference between breaking rock (i.e., limestone or granite) and breaking concrete (recycle operation)? If so, what is the difference?
Answer: Again it’s not enough to just provide impact, especially when dealing with many different materials and sizes. For example, you need a different frequency of impact when making rip rap versus breaking large boulders. Generally speaking, it is best to provide high frequency and low impact when breaking small rock and thin concrete. Low frequency and high impact is best when breaking large rock and thick concrete. Limestone and sandstone are as different as granite and concrete. When dealing with these extremes, which are very common, I recommend that a variable-frequency impact breaker be considered. This design is many breakers in one and addresses extreme rock breaking conditions. If a variable-frequency breaker is not available, try to manually adjust the breaker to meet the conditions.
Question: With the improvement in excavator design, are breakers with shock absorbers that beneficial?
Answer: Recoil and rebound energy is the adverse reaction from impact. (For every action there is an equal and opposite reaction). Breakers that are designed for mining applications should be equipped with shock absorbing systems that remove most of the recoil shock. Not only does this extend the carrier’s life, but it can allow the user to install a larger breaker on a specific carrier. We now find ourselves installing the newer, more powerful breakers on smaller carriers, which makes shock isolators a must. Without shock absorbers the carrier may have to be one or two sizes larger—a huge expense when considering the cost of excavators.
Question: What features do you think should be incorporated into a breaker’s design?
Answer: Breakers can be fragile under misuse. Anything a manufacturer can do to make the breaker more forgiving is a big plus. In recent designs, we have focused on making breakers more resistant to misuse and as powerful as possible. It’s a double-edged sword. As soon as the user is happy with reliability he will want more power. Reliability, along with consistent performance, is what most users really want.
Question: Most often, when one of our breakers fail, we’re told that it’s due to operator’s error. How can this be so?
Answer: The top breaker manufacturers do their level best to provide the best products they can. They don’t want failure. It’s not in anyone’s best interest to have an unreasonable failure. One big advantage manufacturers have over the user is that they see multiple failures. Repeated failures in the same area do a couple of things. First, if it truly is a flawed design and the manufacturer does not make corrections, he will not be around long. He will certainly want to make corrections before the word is out and his market share suffers. Second, if the breaker is providing adequate energy to break the material, then from the manufacturer’s point of view, it is doing a good job.
If the operator is doing his best and the breaker manufacturer is doing his best, then where is the problem? They don’t understand each other. Most failures arise from a lack of understanding. The best racehorse fails if not ridden properly. It’s all about communication and a willingness to learn. The only way to improve the situation is to require that the operator be trained in the proper use and maintenance of the breaker. Don’t give the manufacturer an opportunity to avoid his responsibility to provide the best value to the customer.
Question: What is the most powerful breaker on the market?
Answer: I think of a breaker as production equipment. Regardless of the market or the type of user, most want the greatest production for the investment. The big problem is that there are few measures of breaker production available. The manufacturers do have all kinds of information, such as production charts. Most are not close to reality, but at least it’s a starting point. The reason the charts don’t reflect reality is that manufacturers get very little, if any, feedback from the users. It’s a Catch 22!
I have measured production of many brands of breakers and have come to one great conclusion. What good is a statement about power if it is not proven? In addition to an energy rating, let’s have a breaker production contest. Then, and only then, will we know what brand and model is the most powerful as well as most productive.
Question: What should be my greatest concern when purchasing a breaker?
Answer: Regardless of whether your interests are in manufacturing or crushed stone production, our industry is changing. I know it seems like every opening statement has some new variation on the word “change”—that’s probably one of the few things in our lives that won’t change. There is a great difference in breakers! There are new products and improvements being introduced at a very fast pace. The best advice I can give is to make an informed decision when purchasing equipment. Require that the manufacturer and the distributor provide the resources that will lessen the possibility of failure.
You should be concerned with the way the breaker will be used on the job. The most common practice, on the producer’s side, is to aim for high production at any cost. Untrained operators are very common. You should avoid disregarding the warning signs that can save costly repairs. You should also avoid trying to get one more ton of production at the risk of equipment failure. Take every opportunity to learn and benefit from the vast knowledge that exists. When equipment is pushed beyond its limit, brace yourself for the worst. No company can continue profitably if its motto is “Production at Any Cost.”