Heavy equipment machinery

April 29, 2007

The ever-growing world of compact machines

Filed under: Compact Excavators

BOBCAT pioneered the skidsteer market and continues to be the world market leader, however the composition of the company’s product line has expanded rapidly in the past few years.

The Bobcat product range now includes mini excavators, backhoe loaders and telescopic handlers. There are now all-wheel-steer and track variants of the skidsteer loader and Bobcat has entered the stand-on mini loader market.

Bobcat Australia’s marketing manager David McMurray sees these machines complementing each other, and these thoughts are behind Bobcat’s X-change mounting system whereby many attachments can be interchanged between different Bobcat machines - this has been an advantage in the Bobcat Rental business.

While the skidsteer loader is now a highly developed tool handler and the mini excavator is increasingly seen in this role, the telescopic handler is also being used now with a range of attachments.

David believes that the skidsteer loader is approaching the peak of its development. The move to rubber track loaders allows the loader to work in soft ground conditions, although on a dry continent like Australia David sees few applications for a dedicated compact tracked loader. He does see a limited market for the all-wheel-steer loader in conditions where a combination of minimum ground disturbance, high ground speed, flexibility and good horsepower are required. He considers these machines an alternative to small articulated wheel loaders.

However he sees the greatest untapped potential in telescopic handlers. He believes that for applications requiring over 80hp an operator should be looking at a machine other than a skidsteer, with the telescopic handler the most likely candidate. He also believes that the telescopic handler offers better value in many situations than a tool handler or small wheel loader.

The other area for potential is in the micro machines that essentially replace human labour. The lifting restrictions imposed by OH&S guidelines mean that for many tasks employers should be looking at mechanical handling alternatives. David believes that many employers are yet to appreciate the potential impact of these restrictions.

The compact end of the telescopic handler market (app. 2m height and 2m width) has been a growth area. At one time Terex had this market to itself. Now, however, Dieci, Manitou and JCB offer machines in this range.

Australia has been relatively slow to adopt telescopic handlers, and there is still room for significant growth. Their potential for taking a range of attachments has not been fully exploited, and their ground clearance, speed and stability show up favourably against other classes of compact machine.
In the micro end of the compact equipment market local manufacturers Dingo and Jaden virtually sell these machines as quickly as they can make them. They now have excellent hydraulic output for their size and a wide range of attachments to exploit this.

These machines have also been sold overseas and their potential has been realised by bigger producers such as Bobcat and Thomas, who now have their own micro machines. The Bobcat machine uses rubber tracks. Rubber tracks are seen on a lot of micro equipment overseas and make sense in terms of stability and minimising ground disturbance on machines for which speed is not a major requirement.

There is considerable scope for this sector of the market to grow as a labour substitute - either through economics or regulated necessity. Machines in this sector are generally of stand-on or walk-behind operation, avoiding the need for a ROPS - almost an impossibility in this size of machine.

Avant bridges the gap between the micro and conventional compact machines, with operators sitting on the machine under a protective structure. An articulated machine minimises ground disturbance, while a telescopic boom option allows the Avant to load small tippers. The latest updates -as with all compact machines - offer more engine and hydraulic power to improve the performance of an increasingly wide range of attachments. It is remarkable to think that some very functional planers are offered for the Dingo mini loaders.

At the other end, compact dimensions are appearing in increasingly heavy excavators, with a number of manufacturers now offering machines with minimal tail swing in the over-20t market. Previously few excavators were sold in the 7-20t range, however this is now becoming a very popular and increasingly crowded market.

Compact dimensions are now coming without a major performance compromise, however there is still a significant price difference. Many owners are now saying that it is worth paying that price for the versatility that such a machine offers.

Buckle up for the ride because the compact equipment market still has a long way to run - and it’s in a hurry to get there.

http://www.infolink.com.au/articles/CF/0C00CACF.aspx

Buying a Compact Excavator

Filed under: Compact Excavators

Most concrete contractors don’t do extensive earthwork prior to placing concrete. There are, however, many situations where you need to do some digging, and the invention of the rubber tracked compact (or mini) excavator has been a real boon for those times.

Compact excavators are generally defined as those with operating weights less than 6 tons, and they go as low as 0.9 ton. If you don’t currently have a compact excavator and are thinking of buying, leasing, or renting one, there are a few advantages over the traditional loader backhoe that you should consider. “They have the ability to get into tighter spots,” says Luke Secrest with Advanced Foundation Solutions—The Basement Guys, in Columbus Ohio. “For a long time if you wanted to do anything around your house, you had to bring in a big piece of equipment. We have rubber tracks on our equipment because of the low pressure on the ground and because we go across a lot of driveways and parking lots where it could cause damage. Also, the maintenance is less; as you get into the smaller engines, they are a lot easier to maintain. We use a lot of the small Kubota machines, and nothing ever breaks. Although the operation is pretty much the same as on a full-sized machine, it’s easier to train someone to use the small stuff because the hardest thing about training someone on equipment is depth perception. When you put someone on a small machine, it’s easier for them to grow into the bigger equipment.”

Another big advantage with the compact excavators is the ability to dig in the offset position (see Glossary, p. 34, for an explanation of this). With the boom slewed one way and the carriage rotated the other, offset digging allows the operator to excavate directly adjacent to an existing structure. It also allows the tracks of the excavator to remain parallel to the trench for efficient repositioning.

The limitation with compact excavators, of course, is that you have a limited digging depth and force. “But you always have some limitations on any equipment,” says Secrest. “You’re not going to do a major freeway project with one.”

Purchasing considerations

If you are thinking about buying a compact excavator, the first thing to consider, of course, is whether you really need one—or you just want one because they are so cool. “But if a contractor is looking at a loader backhoe,” says Brian Rabe, product specialist for Mustang, “he might be able to get a compact excavator and a skid-steer loader that have much more flexibility for about the same cost.”

So if you are going to buy one, then the first decision is size (digging depth, digging force, dump height, reach), which directly relates to the applications you have now and expect in the future. Get a machine that is big enough to do the job, but don’t go too big. “If you buy a 16-ton machine and finish the job in an hour and then it just sits there for the rest of the day, that’s not a good use of your money,” says Ingersoll-Rand’s Georg Seyrlehner, “when you could have bought a less expensive 6-ton machine that would have finished the job in three hours.”

There are many manufacturers making these machines today (see below). Some factors to consider when, comparing manufacturers and models are:

  • Cycle time refers to the cycle time on the cylinders that control slew speed and boom speed; what kind of productivity do you need?
  • Auxiliary hydraulic flow rates and pressures are relevant to attachment capacity and compatibility; make sure the machine has the flow and pressure you need.
  • Travel speed is important on larger jobsites.
  • Operator comfort and visibility
  • Size/configuration of controls
  • Accessibility of engine and hydraulic components

  • Manufacturers of Compact Excavators
    Zero swing (sometimes called zero tail swing or zero house swing) is the hottest thing in the compact excavator market today—but it adds some cost. “If you are buying a zero tail swing machine,” says Bobcat’s Greg Rostberg, “make sure it is a true zero tail swing. Some companies sell a zero tail swing machine, yet the counterweight kits can extend outside the tracks. This could limit slew rotation (and minimize spoil placement opportunities) and increase the potential for damage to the machine and peripheral objects.”

    Operator comfort can be a big issue. “I tell people to sit in the cab for a long time,” says Mustang’s Doug Snorek. “Then you begin to get a feel for whether it is cramped and what kind of visibility the operator will have. Some of the zero swing machines had to sacrifice cab comfort and some are more difficult to service because of difficult accessibility to the engine compartment.”

    So what does a compact excavator cost? The smallest machines start a little under $20,000. At the top end of this category (1.2 tons), prices range from $60,000 to $100,000.

    Glossary of Compact Excavator Terms*

    Arm—Also referred to as the dipper, it is the structure that connects the excavator’s attachment to the boom.

    Arm force—The excavator’s ability to produce a pulling force, using the arm hydraulic force. This is also referred to as dipper force or crowd force.

    Attachment—Any device coupled to the workgroup to complete a prescribed task. The most common attachment for an excavator is a trenching bucket. Other attachments may include grading buckets, hydraulic breakers, plate compactors, augers, or rippers.

    Auxiliary hydraulics—A dedicated source of pressurized hydraulic oil, intended to provide oil flow for specific attachments. The excavator’s pump system is the source of the oil, and it is routed to the attachment via tubelines and hoses on the workgroup.

    Backfill blade—A hydraulically activated blade attached to the undercarriage and used for grading and backfilling. It can also be used as a stabilizer during digging and can be used to increase dump height and digging depth depending on its position in relation to the workgroup.

    Boom—The primary component of the workgroup that is attached to the house structure via the swing frame. It supports the arm and attachment.

    Bucket breakout force— The excavator’s ability to produce a “prying force” using the bucket hydraulic circuit.

    Cab—House.

    Compact excavator—Also called “mini” excavators. Compact excavators generally include those with operating weights of 12,000 pounds (6 tons) or less and digging depths of 14 feet or less.

    Control patterns (ISO or Standard)—The operating pattern of an excavator’s joysticks. There are two predominant joystick patterns on compact excavators. When operating in the ISO pattern, the right-hand joystick controls the boom up/down function and the left-hand joystick controls the arm in/out function. With the “standard” pattern, these two functions are reversed.

    Counterweight—A weight added to the rear of the excavator’s house structure in an effort to improve its lifting characteristics. Counterweights are also added to the machine to accommodate variations in arm configurations such as long arm options or extendable arm options.

    Cycle time—Cycle time refers to the amount of time, usually in seconds, that a particular function takes to complete (for example, to lift the boom).

    Dig depth—The maximum depth that the excavator is able to dig on flat, level ground.

    Dipper—Arm

    Dump height—The clearance required for an excavator to dump the spoil from its bucket.

    Flotation—The machine’s ability to traverse soils or surfaces that have low load-bearing capacity.

    Gear pump system—An oil supply mechanism that produces oil flow from rotating gear assemblies within a pump housing. A gear pump system has a fixed displacement and requires a change in pump shaft speed to affect pump volume.

    Ground pressure—The force that the machine exerts on the surface, measured in pounds per square inch (psi). Lighter excavators do not necessarily have lower ground pressures, depending on the size of the track footprint.

    House—Also sometimes called cab, includes the operator compartment, the engine compartment, and the hydraulic pumps. The house structure is attached to the undercarriage with a swing bearing that allows it to rotate or slew, typically 360°.

    Independent boom swing—The boom swings independently of the rotation of the house. The primary purpose of boom swing is for offset digging around obstacles or along foundations, walls, and forms. A secondary use is cycling in areas too narrow for cab rotation. Independent boom swing is one of the major advantages of a compact excavator over other excavation equipment.

    Offset digging—The practice of excavating with the boom offset to either the right or the left. Offset digging is accomplished by using the independent boom swing capability of the compact excavator.

    Piston pump system—An oil supply mechanism that produces oil flow from a rotating assembly of small pistons within a pump housing. Unlike the gear pump system, the piston pump system has the capability to vary oil flow independent of pump shaft speed.

    Reach at ground level—Measured from the excavator’s center rotational axis to the tip of the standard bucket, at ground level.

    Slew—Slewing means rotating the excavator’s house assembly. Unlike a conventional backhoe, the operator can “slew” the entire house and workgroup upon the undercarriage for spoil placement. This introduces minimal fatigue to the operator as his body is traveling with the workgroup for maximum visibility and minimal body movement. Compact excavators can slew a full 360°.

    Tail swing—Refers to the rear overhang of the excavator as it rotates upon the undercarriage. It is measured from the central rotational axis to the furthest rear point of the machine.

    TOPS/ROPS—TOPS is an acronym for Tip Over Protective Structure. ROPS is an acronym for Roll Over Protective Structure, A TOPS or ROPS rating defines the protection afforded an operator in the event the machine would tip or roll over. The structural integrity of an operator’s compartment must meet standards prescribed by ISO or SAE to be certified as TOPS or ROPS.

    Tractor/loader/backhoe (TLB)—Main competitor of the compact excavator, the TLB is limited to a maximum of 180° workgroup movement, unlike a compact excavator that can slew 360°. The TLB typically features fold-down stabilizers (outriggers) that often restrict its use in confined areas.

    Undercarriage—Supports the house structure and includes the tracks, drive sprockets, rollers, and idlers.

    Workgroup—The workgroup consists of the boom, the dipper, and any attachment.

    ZHS-Zero House Swing-Sometimes incorrectly called zero tail swing, this means that the house and counterweights stay within the machine’s width during slewing. This prevents accidentally damaging trees, buildings, and the machine. Zero house swing also permits easier spoil placement in tight quarters.

    360° cab rotation—The ability to continuously rotate the house 360°. Because of the compact excavator’s 360° rotating house, an operator can dig on one side, then rotate and unload the dirt into a truck or onto a pile several yards from the hole. This allows for enhanced spoil placement, superior visibility and minimal operator fatigue.


    http://www.concreteconstructiononline.com/industry-news.asp?sectionID=
    717&articleID=239490&artnum=1

    Side by Side: Trenchers vs. Compact Excavators

    Filed under: Compact Excavators

    Popular, affordable and highly productive, these two machine types have helped lay a lot of cable and pipe in the ground in the last few years. And while both can do the work, we asked two experts from Ditch Witch — Brent Bolay, senior product manager over trenchers, and Mike Lumbers, senior product manager over compact utility products — how these two machines stack up against each other in residential utility installations.

    Size and price
    The average dig depth for utility installations in residential applications is between 40 and 48 inches, Bolay says. A basic trencher that digs to this depth will have a 20- to 30-horsepower engine and cost in the neighborhood of $35,000 to $40,000. The most popular compact excavator, Lumbers says, is the 2.5-metric-ton size class, and it also uses a 20- to 30-horsepower engine and costs about the same. A big difference emerges when you need a trencher to go deeper. The 2.5-metric-ton excavator has no trouble digging to 8 feet or more, but a trencher that can go that deep will require an engine with 100 horsepower or more and cost up to $90,000.

    Lifecycle costs
    Except for bucket teeth and the replacement cost of the rubber tracks at 1,500 to 2,000 hours, fuel and regular maintenance are your only day-to-day costs with a compact excavator, says Lumbers. The teeth, digging chain and sprockets on trenchers are considered wear items and are replaced fairly often, Bolay says, something people unfamiliar with trenchers need to be aware of. Yet even with the trencher’s higher consumable costs, the differences tend to even out when its productivity is taken into account.

    Productivity
    For straight-line trenching at average depths on unencumbered jobsites, trenchers flat out take the lead. Under good conditions a trencher can work three to four times faster than an excavator, Bolay says. "If it’s a fairly open jobsite and there are not a lot of underground or surface obstacles, you can work productively and leave a cleaner jobsite with a trencher than a compact excavator," he says. Another place where trenchers excel is in wooded areas where tree roots make for sloppy, slow digging with a bucket. "But if you’re working in a housing area and you have short runs and underground obstacles a compact excavator might be the right choice," he says.

    Versatility
    Compact excavators can do a lot of things a trencher can’t do, especially when outfitted with attachments. "With a compact excavator you shouldn’t have a foot-per-minute goal," Lumbers says. "It’s a good choice if you’re looking for a piece of equipment that you can keep busy on the jobsite for different tasks such as setting utilities, using a hammer or a grapple, or doing pit work."

    But a trencher is not a single-minded machine either. Many can be outfitted with a backhoe attachment that fits on the front end. When rocks, concrete or asphalt stand in your way, the boom and chain can be replaced with a wheel and rock teeth. And in soft soils, you can set up a trencher with a vibratory plow attachment and plow in cables faster than any other method.

    Wringing Huge Work Out of Compact Excavators

    Filed under: Compact Excavators

    More than 45 hydraulic-excavator models between 20,000 and 40,000 pounds compete for your purchase dollars. Enough money is being spent on machines this size that the scent of cash and desire to supply the big rental houses attracted no less than four manufacturers to field their first excavators in the size class over the past 30 months.

    Four of the six models brought to market by new competitors Ingersoll Rand, Takeuchi, Terex, and Yanmar combine features in a way that’s indicative of why the excavators in this size class can be King Kong compacts. They’re nearly-100-hp machines with features common to compacts such as swinging (or articulated) booms, minimum swing radius, and options for rubber or steel tracks.

    Takeuchi’s 31,500-pound TB1140, for example, is the largest excavator in the North American market whose standard equipment list includes a boom mounted to the upper frame at a hinge point like so many compact excavators. The swinging boom impinges on the machine’s power somewhat (its lifting capacity over the idlers at a 20-foot radius with the load at ground level is comparable to machines that weigh a ton less). But a swinging boom allows the machine to dig a hole with sides parallel to its tracks the entire width of the machine without need for repositioning.

    Caterpillar, Komatsu, and Kobelco offer alternatives to the swing boom usually called offset boom machines. These units will also excavate parallel to the tracks the full width of the machine, but accomplish it with a boom that has two joints rather than mounting a rigid boom with a hinge to the frame. Optional offset booms on Cat’s 314C and Kobelco’s 135SRLC actually push the feature up to the 33,000-pound size range.

    Nineteen of the 10- to 20-ton excavators available today — nearly half — are reduced-swing-radius, or zero-swing-radius machines. The counterweight and boom on these machines extend only inches beyond the track width so they can work effectively in very small or congested areas without risk of swinging into obstacles. Manufacturers produce reduced-radius machines by installing a larger counterweight and changing frame geometry to preserve lifting and digging capacity.

    Most machines in the class were upgraded to the latest technology in 2003 and 2004 when they had to comply with EPA’s Tier 2 emissions regulations. Reduced-swing-radius machines have dominated new introductions since then.

    "There is increasing demand in certain applications for zero swing machines to work in smaller and smaller spaces, while maintaining high outputs," says Dave Hardwick, excavator product manager at JCB. "The push to constantly reduce the build time on developments has increased the need for high output, high efficiency machines that can carry out large amounts of ground works and utility works every day."

    The heaviest reduced-radius excavator in this class is Komatsu’s 36,400-pound PC158USLC-2. With an 8 foot-2 inch stick, it can pick up 8,700 pounds at a 20-foot lift radius. But reduced-radius excavators do sacrifice some digging and lifting leverage in order to get a shorter upper frame.

    Comparisons are telling. Komatsu’s reduced-radius PC138USLC-2, at an operating weight just under 31,000 pounds, develops stick-digging force of 13,670 pounds. The conventional PC120LC-6 (3,200 pounds lighter) applies 13,890 pounds of stick-digging force.

    John Deere’s reduced-radius 135C RTS, with an operating weight of 30,400 pounds, moves the stick with 12,800 pounds of force. The 28,800-pound 120C (1,600 pounds lighter) develops 13,172 pounds of stick force.

    "As customers continue to look for improved efficiencies in their business, smaller machines are asked to do more demanding jobs in a wider variety of applications," says Jason Williamson, excavator product manager at Caterpillar. "Machines in this size class are easy to transport and very maneuverable. They can be general purpose or dedicated machines and can be used in many different digging and tool applications."

    This dichotomy of expectations for 10- to 20-ton excavators — compact machines that transport on a tag trailer behind a dump truck but are capable of significant productivity — is underscored by a marketing emphasis on the efficient productivity of the current generation.

    "The data shows that even though Tier 2 machines were updated and power output was increased, fuel efficiency also increased," says Dave Pooley, excavator product manager at Hyundai. As an example, he notes that the R160LC-7 has 11 percent more horsepower than the Dash-3 machine it replaced, but its rated fuel consumption is 1.6 percent less. Horsepower didn’t change in the R140LC with the Dash-7 version, but fuel economy improved 4.5 percent.

    As with most diesel-powered equipment, emissions regulations and the computer control of fuel injection necessary to meet exhaust limits paved the way for this sort of advancement in all excavator brands. Excavators squeeze all the benefit from digital control by coordinating a controller on the engine with one in command of the hydraulic pumps and motors.

    To illustrate how far control technology has come, consider Komatsu’s PC160LC-7 compared to its predecessor, a nearly 3,000-pound-heavier PC150LC-6. The PC160 delivers 29 percent more bucket digging power and its arm-digging force and lifting capacity are both 11 percent greater.

    Electronic systems are also providing an unprecedented amount of quality information about the recent history of a machine’s performance and operating problems.

    "The Deere Machine Information Center (MIC) is a data logger integrated into each machine," says Mark Wall, John Deere excavator product manager. "This data logger records machine information such as engine rpm, hydraulic oil and engine coolant temperature, pump pressures, machine alarms and codes, time spent traveling, time spent swinging, and idle time. The information can be transferred to a customer’s computer via a Palm Pilot. Reviewing this information, the customer can make important decisions concerning his machine and application."

    Technology has not advanced effortlessly, however.

    "Most people agree the laws to improve the air quality are necessary, but we have seen in the past few years that the technology [necessary to satisfy air-quality laws] is outrunning the trained engine specialists and all too often the engine suppliers are not keeping on top of the distributor network to bring [training] standards up to where they should be," says Dave Pooley, excavator product manager at Hyundai. "Engines with computer control are the way of today and the future. Manufacturers have to cope with that and increase training programs and simplify the way information in the computer is downloaded and disseminated."

    Tier 3 will apply to the 100-hp and larger engines in this size class in 2007, so look for a spate of new-machine introductions and major line renovations later this year. Only a third of the excavators in the class have engines 100 horsepower or larger, though.

    Machines up to 100 horsepower will have to comply with Tier 3 emissions limits in 2008, so most of the excavators between 10 and 20 tons that have not yet been upgraded will likely get a major facelift before the end of next year.

    Specifications: 15- to 20-Ton Excavators (by weight) Operating Model Arm (stick) Weight (lb.) Max. Dig Length Lift Over Depth Net End (lb.)* HP
    * 20-foot radius at ground level (Bucket sizes range from 0.3 to 1.5 cubic yards.)

    Mini-Excavator Gains “Real-Machine” Status

    Filed under: Compact Excavators

    Our friend Gene Held has been moving dirt for 30-plus years — many years with contractors, and more recently as an instructor in Local 150’s (International Union of Operating Engineers) Apprenticeship and Skill Improvement Program. Held’s primary job is to help young apprentices become competent, safety-conscious operators of hydraulic excavators and backhoe-loaders, so it’s to him we turn when we have a new machine of this type to evaluate.

    We worked with Held most recently in late April, when Caterpillar’s Matt Mumford arranged with nearby dealer Patten Equipment to deliver a brand new 304C CR (Compact Radius) mini-excavator to Local 150’s new training facility (presently under construction) near Wilmington, Ill. Although Mumford wanted to supply a 304C with its optional coupler and optional hydraulic thumb, the machine arrived with a standard pin-on bucket. The mini-excavator market is so hot these days, explained Mumford, that choices for our evaluation machine were limited.

    Equipped with a cab (optional), air-conditioning (optional), rubber tracks, blade and counterweight (as was our test machine), the 304C CR weighs in at about 10,800 pounds. The mini-excavator, which is manufactured by Caterpillar in Japan, is powered by a 42-hp (net), Tier-2-compliant Mitsubishi diesel. The standard digging arm (stick) yields a maximum digging depth of 10 feet 10 inches, and the "long arm" (which our machine used) delivers 12 feet 1 inch. Both sticks are available from the factory with integral mounting bosses that facilitate installation of the optional hydraulic thumb.

    The 304C has a "CR" designation, because the standard rear counterweight can overhang the tracks by up to 4 inches. The counterweight is installed to improve lifting performance, which, says Caterpillar, may be compromised to a degree in some zero-tail-swing designs. If need be, the counterweight can be removed to provide zero tail swing.

    First look

    Probably like many professional equipment operators with years of experience, Held admits that he didn’t take the mini-excavator too seriously when it first appeared on the North American construction scene. But he’s changed his tune, he says, based mainly on the performance of a couple of mini models added to Local 150’s fleet in the recent past.

    "It’s amazing how much power these little things have," says Held. "When they first came out on the market, I thought: ‘Those little toys, what the heck would you want one of those for?’ But they really are strong, versatile machines, and now you see them everywhere."

    So, now that we knew Gene wasn’t going to be a hard sell on the mini-excavator concept, Mumford gave us a quick tour of the 304C’s cabin. Held’s observations as he climbed into the cab were, first, the sliding door, which he considered an excellent feature, and then, as he settled into the seat, the machine’s excellent all-around visibility. Mumford asked Held to unlatch the front window and slide it upward into the roof, an operation easily done with the assistance of gas struts, and then to remove the lower front glass, which lifts easily out of its frame for storage against the left rear window.

    "When it’s warm, I like the bottom glass out," says Held, "because it’s usually dirty and you can’t see as well into the trench. This is an easy-to-use system. Some front windows you really have to tug at."

    Mumford explained that a significant design change for the 304C (compared to its predecessor) was the replacement of foot pedals — for boom swing and auxiliary hydraulics — with thumb controllers in the pilot-operated joysticks. The net result, he said, is easier control of these functions and more foot room.

    "Foot room is important," said Held. "I don’t like operating with my knees under my chin."

    Our test machine was equipped with a push blade (it’s standard), and the pilot-operated blade controller has a forward detent to place the blade in a float condition. Soon to be available, Mumford said, is a hydraulic angle blade that can be rotated 25 degrees right or left to minimize repositioning when backfilling. The new blade’s controller will be single-lever and pilot-operated.

    When Held noted the two-speed travel switch on the 304C’s panel, Mumford pointed out that the travel system now has automatic-shift capability. You can place the switch in the "rabbit" position, he said, and the system will automatically downshift when it encounters a load — or when the machine turns. He noted, too, that the 304C now has an auto-idle feature, which is aimed, he says, at enhancing fuel economy and lowering sound levels.

    When Mumford told Held that the 304C was radio-ready, we asked Held if he liked a radio when he was working.

    "No, I seldom use it. The kids [his apprentices] do — they like jammin’ when they’re operating. But I don’t. I’m from the old school, so I like to concentrate on what I’m doing. A radio’s nice sometimes if you’re out by yourself, but I want to hear how the machine’s running, so if something goes wrong, I’m aware of it. But that’s just one guy’s opinion."

    The 304C is fitted with auxiliary hydraulics as standard equipment, and our test machine, Mumford told us, also was fitted with an optional auxiliary package that allows, for example, use of a rotating shear. The secondary auxiliary functions, he explained, work off the boom-swing circuit, and an in-cab switch diverts oil from one function to the other. A changeover valve in the engine compartment allows the main auxiliary hydraulics to function as either a one-way or two-way system.

    In the dirt

    When we put the 304C to work, we first asked Held to position the machine’s tracks parallel with the wall of the new facility, then to position the cab and boom so as to dig closely parallel to the wall. The intent was to get his thoughts on this compact machine’s basic maneuverability and controllability. After 10 minutes or so, we asked what he thought.

    "The offset boom gives the machine a lot of flexibility; it’s great for working in tight quarters like this. Hydraulic functions are very smooth and easy to feather — not jerky at all — and that’s important when you’re working against a structure that you dare not damage."

    The next exercise was trenching in a moist, heavy-clay stockpile. As we watched Held work, our overall observations were that 304C seemed quite a flat-footed digger (it has more track-on-ground than its predecessor) and that its digging motion was consistently smooth. Mumford told us that Cat excavators, mini-models included, are known for high stick forces, and now, he said, bucket-breakout force also has been significantly increased in the new C-Series. But what did Held think about 304C’s trenching performance?

    "It’s got a lot of breakout power in the stick, and that’s what I like. When you’re coming in with the stick, you don’t want to have to pump the bucket to get through the cut. It’s also very smooth; you could finish grade with it."

    How about stability when you were pulling through some of the tough spots?

    "It was very stable — as long as you have the blade down in front. I noticed, too, that even with the longer stick, when you come up out of the hole, you don’t get into the blade with the bucket. On some machines, especially those with an extendible stick, you can hit the blade if you’re not careful."

    Next, Held used the 304C’s blade to backfill the trench.

    "It’s got plenty of pushing power," he said, "and blade control is smooth. And when you put the blade into the dirt, it doesn’t dive into the cut. Some machines will do that, and you’re always having to pull the blade up."

    As a final exercise, Held placed a chain through the 304C’s lifting eye (which is integral with the bucket link) and picked the top ring of a concrete manhole.

    "It has good lifting power," he said. "I don’t know what that ring weighs, but I’ll bet that I could have lifted the bottom section, too, if we had the rigging to hook it up. I could raise the blade and travel with the load, and it didn’t feel unstable at any point."

    We then found a shorter chain that allowed making the same pick and keeping the load tucked in sufficiently to swing over the side. Again, according to Held, the machine was strong and stable, "as long as you keep the load in close and keep the blade down."

    What impressed us, also, is the precision with which Held could replace the massive ring over the neck of the manhole — likely the result of his skill and the machine’s controllability.

    Final thoughts

    Mumford told us that Caterpillar’s primary focus when developing the C-Series mini-excavators was to continue to enhance operator comfort (hence the larger cab with its new amenities) and to increase digging performance (which seemed to impress Held).

    So, Gene, do you have any parting thoughts about this mini?

    "I’ll come back to the stick power it has. I like to dig only to about the height of the teeth, and to move the stick though an arc from about the 8-o’clock position to the 5-o’clock position.

    "Because I’m not digging deep, I can feel the bottom of the trench. Some guys will just roll the bucket into the ground to load it, but you’ll never dig around utilities doing that. You always want to shelf the material down. This machine has the power to dig the way I want. I think Cat has done well on this particular machine."

    Gehl adds new compact excavator

    Filed under: Compact Excavators

    Gehl Co., a manufacturer of compact equipment for construction markets, has added a 3-ton model 383Z zero-tail-swing compact excavator to its line.

    The new Gehl 383Z Excavator features zero-tail-swing maneuverability, which allows the machine’s superstructure to rotate entirely within the tracks. The 383Z excavator can operate close to walls and obstructions without risk of contact. Its small size, weighing 7,826 pounds with a canopy and 8,002 pounds with a cab, and maneuverability make it a perfect fit for operating on congested sites without obstructing traffic.
    Other excavator manufacturers compromise operator space and serviceability in order to gain zero-tail-swing maneuverability. The 383Z excavator, however, boasts an innovative design that enhances both operator space and serviceability.

    The size of the operator’s compartment is maximized by mounting the 29-horsepower Yanmar diesel engine on the side of the machine, and the hydraulic and fuel tanks on the rear of the machine. This provides the operator with more space and legroom. The operator’s compartment has a fully adjustable suspension seat and armrests, allowing the seat to conform to the needs of the operator to reduce operator fatigue. The controls and instruments are ergonomically located for ease of use.

    The canopy and cab meet or exceed all ROPS, FOPS and TOPS requirements for increased safety. The cab option brings comfort to a whole new level. Cabs come standard with air-conditioning, heater/defroster, interior light, windshield wiper, windshield washer system and the ability to open the cab windows for natural ventilation.

    In order to maximize serviceability, the cab easily tilts to the side for quick access to service points for hydraulics, rotary transmission, control block and the air-conditioning unit. One large, lockable engine hood opens to allow complete access to hydraulic system test ports, hydraulic pumps and all engine components. These two features add up to best in class serviceability.

    The 383Z excavator has a longer undercarriage than other compact excavators in its class. This provides more stability, allowing it to perform like a conventional-tail-swing machine under heavy digging conditions. The excellent stability of the 383Z excavator provides powerful digging and lifting performance.

    With the highest tractive effort in its weight class, the 383Z excavator can push more material in an efficient manner. The Auto-2-Speed drive motor load sensing system maximizes efficiency as well, by automatically shifting between low and high range to improve cycle times, thereby reducing operator input.

    In addition to its many great features, the components used on the 383Z excavators are made to last, which result in lower owning and operating costs. For example, all pivot points on the bucket, dipper arm, boom and swing brackets use spiral-grease groove bushings. Not only are they easily replaceable, they guide the grease all the way around the pivot pins extending service life.

    Versatility is another benefit of the 383Z excavator. The smooth, powerful hydraulic system, the 383Z excavator is able to work with a wide array of attachments: thumbs, hydraulic hammers, earth augers, grapple buckets, trench fillers and many more!

    http://www.concretemonthly.com/monthly/art.php?2537

    Hitachi upgrades compact excavators

    Filed under: Compact Excavators

    Hitachi has upgraded its zero tailswing mini excavators with the introduction of Zaxis series. The models coming to Australia will be the 23kW 27U and 35U, and the 30kW 40U and 50U. These represent substantial power increases for the 27U and 40U. The model designation roughly indicated the weight (e.g. 27U~2.7t) with actual weight depending on whether a canopy or cabin, and rubber or grouser shoe tracks are chosen.

    The largest two models now have a single load-sensing variable displacement hydraulic pump with an output of 110 l/min - a substantial increase on their predecessors.

    Improvements have also been made in the smoother pilot control levers that require 25% less control force, improved service accessibility with wide-opening covers, greater durability in bushes and wear surfaces and reduced engine emissions.

    Also new are the 7t Zaxis 70 with standard body and the 7.5t Zaxis 75US with zero tailswing. Both are offered with the choice of standard or offset boom and share a 40.5kW engine, extended service intervals and a large cab with reinforced corner protection. They have the same durability improvements as the mini excavators. These machines are designed as a scaled down large excavator, rather than as a large mini excavator.

    Geoff Taunton of Tauntons Excavations (TE) was the first to buy one of the new Zaxis 75 7.5t zero tailswing machines. This machine is air-conditioned, and specced with a dozer blade, rubber track pads and offset boom. It has been plumbed for screw pile installations using a planetary drive head.

    TE runs seven excavators up to 12t, as well as four backhoe loaders and a skidsteer. The company specialises in screw pier installation but also digs footings and drains, cuts out house pads and does some civil work for larger contractors. The excavators up to 8t all have zero tailswing, rubber tracks and offset booms. Geoff has found that the latest generation of 7-8t machines will do 90% of the work done by 4-5t machines as well as 90% of the work done by 10t machines. He is planning to adjust his fleet mix accordingly.

    Geoff believes in designing the screw piers to suit each job. He conducts his own soil tests, does his own design work, and carries six different sizes of drive heads in his fleet to match different sizes of pier up to 50t capacity. His success in this specialised field is such that apart from generating his own work he often acts as installation subcontractor for other companies.

    Craig Carson of Craig Carson Bobcat & Tiptruck Hire expects to take delivery of a similar Zaxis 75 shortly. It is similarly specced with offset boom and rubber track pads. Craig is trading an existing excavator of similar specification. It is fitted with a JB tilt quick hitch, buckets, ripper, stick rake, trench compactor, roadbase compactor, log grab, rock grab, tree shears, auger, rock trencher and Stanley hydraulic hammer, which will be transferred to the new machine.

    He is very impressed with the JB quick hitch, which has a greater range of movement and a much narrower profile than a convention tilt hitch with hydraulic rams. Craig is looking forward to the smoother hydraulics of the new Hitachi.

    He also operates a 500hp Kenworth SAR tandem tipper the tows a tri-axle tag trailer on which the excavator, a John Deere 260 skidsteer loader and a range of attachments are carried. The loader has an air-conditioned cab with suspension seat, Crossflow tilt bucket, 4-in-1 bucket, broom, forks, stick rakes, ripper, rock trencher, posthole borer, stump grinder, spreader bars, lawn aerator and steel and rubber tracks. The 260 is big enough to load the Kenworth and has proven itself faster than a backhoe loader in this work.

    Craig prefers to operate his machines himself, only employing a casual operator when he has a backlog of work. He has been selective in his client base, with a concentration on government work. He is prepared to operate long hours and to drive anywhere to maintain the service to his clients. His payback for this is rates that are often the envy of his competitors, but he has invested heavily to provide the service. All machines are highly specced and the investment in attachments is the equivalent of an investment in another machine. Tyres and tracks are chosen to minimise ground disturbance as Geoff has regular work at a lawn cemetery.

    The truck is well powered so that it can maintain highway speeds when travelling to country jobs. It can handle a full load in the tipper and the weight of a fully laden machinery trailer without running short of breath. Craig chose a large tipper so that he does not waste the client’s time with constant trips to unload the tipper. So far the investment is paying off well.

    http://www.infolink.com.au/articles/26/0C00CB26.aspx

    April 25, 2007

    Real-world mini excavator prices from BuyerZone buyers

    Filed under: Compact Excavators

    We regularly survey BuyerZone users to ask how their purchases went. We’ve used their responses to provide a sampling of actual prices businesses paid for mini excavators.

    New or used, the size of the excavator you choose will have a huge impact on the price. Quotes below are arranged by horsepower (HP), which usually (but not always) correlates to maximum dig depth.

    When comparing prices of used machines quoted below, keep in mind that users may have different explanations of what "good condition" means, and some don’t specify condition at all. Buying any heavy equipment used can save you quite a bit of money, but requires that you have qualified maintenance staff, a good warranty, or another contingency plan in place.


    New mini excavator pricing

    "Volvo EC15 $24,998. Additional light on arm." [19 HP, 6′ 9" dig depth]
    – City government, Mount Dora, Florida

    "Kubota Kx71-3R1. $29,000 - compact 27.5 HP excavator, 12" and 18" buckets." [9′ 9" dig depth.]
    – Consultants, Holbrook, Pennsylvania

    "Kubota 121, 3 buckets, radio, cab, blade, thumb, rubber tracks, bolt on plate for 3′ bucket, $50,750 including tax." [42 HP, 11′ 6" dig depth]
    – General construction, Snohomish, Washington

    Used mini excavator pricing

    "Cat 301.5 - $9,500." [17.4 HP, 7′ 6" dig depth]
    – Business services, Fairbanks, Alaska

    "Purchased a 301.5 Cat mini excavator … we paid $14,000. 2002 model, great condition." [17.4 HP, 7′ 6" dig depth]
    - Shipping company, Flatridge, Virginia

    "I purchased a 2000 Hitachi EX40U with a hydraulic thumb, 22" & 12" buckets with quick release. Steel tracks with bolt on rubber. It has 2,600 hours on it. It will have a complete service done on it including all oil filters and all oils changed. I paid $26,000, this includes the service and shipping from Canada to Utah." [25 HP, 11′ 2" dig depth]
    – General construction, Spanish Fork, Utah

    "I purchased a 2001 Kubota KX61-2 with 12", 18", and 24" buckets. It has 2,900 hrs on the meter, $13,500 delivered from CA." [27 HP, 9′ 10" dig depth]
    – Construction, Wellington, Nevada

    "$19,200 2001 Volvo EC 35 with thumb, cab and rubber tracks." [36.3 HP, 11′ 3" dig depth]
    – General construction, Raleigh, North Carolina

    "Bobcat Excavator 331. 1,400 hrs, 18 inch bucket, no warranty: $19,000." [40 HP, 10′ 2" dig depth]
    – Utility contractor, Clyde, North Carolina

    "$20,000 - Bobcat 337. $2,000 for 2 new buckets." [48 HP, 11′ 9" dig depth]
    – Welding contractor, San Angelo, Texas

    Mini excavator rental pricing

    "Bobcat 316 mini excavator (super narrow track) $145.00/day (rental) + 10% LDW + tax." [9.9 HP, 5′ 1" dig depth]
    – General contractor, Reynoldsburg, Ohio

    "Cat 301.8c mini excavator. 3 month rental, $1,700/mo with purchase option, $31,000 for 2005 model with approx 70% of rental going to purchase." [18.1 HP, 7′ 7" dig depth]
    – Dentist, Pen Argyl, Pennsylvania


    http://www.buyerzone.com/industrial/mini-excavators/bps-mini-excavator-prices.html

    Rental Yard Finds Success with Compact Excavator

    Filed under: Compact Excavators


    Doug Schmidt, a central Illinois businessman, started his own rental company — General Rental Center — in Decatur, seven years ago. Since he first opened the doors of his independent store, he has been providing both contractors and homeowners with compact equipment that best suits their needs. Today, the president/owner still answers the phone and works the front desk, so he has an exceptional feel for the business, he says.

    This spring, Schmidt added a popular piece of compact construction equipment to his company’s inventory — a compact excavator from the Vermeer equipment dealership in Eureka, Illinois. Even though his new CX229 excavator is in the mid-size range of the Vermeer line, it is on the larger end of the equipment he typically carries, other than a few skid steers. Schmidt says he doesn’t carry large construction equipment in part because other national and regional rental stores in the area have driven down rental rates for bigger machines. So, Schmidt has taken a strategic business approach and made a niche for himself in the smaller equipment rental market.

    It is commonly known in the construction industry that the compact or “mini” excavators have become one of the most popular pieces of equipment on job sites, whether it’s commercial or residential construction. Contractors and homeowners find them to be quite useful pieces of compact machinery for those tough jobs that don’t accommodate larger excavators or backhoes. In addition, the smaller excavators have many of the same features as the full-size models. Those who operate larger excavators and are unhappy with backhoes are quite at home with the compact excavators, according to an article published by the American Rental Association.

    In the short time since he bought the new excavator, Schmidt has developed quite a demand for the digging machine. He says the unit is particularly popular among homeowners as well as contractors. “Contractors are renting the unit to install lateral lines,” says Schmidt, “while do-it-yourself homeowners are using the machine to dig footings and for landscaping projects.”

    Electrical and sewer contractors have been some of Schmidt’s first construction clients — the new model is popular for installing sewage pipes and electrical conduit. These customers find the machine helpful where other larger units could be seen as too large or too much equipment for the job. Homeowners are probably more comfortably seeing a smaller compact excavator on their front lawn, as opposed to a larger excavator or backhoe, which can weigh more and potentially result in more harm to the yard, Schmidt says.

    Tips for Renting a Compact Excavator
    Obviously the appropriate training is important to renting and operating the compact model, but Schmidt says most contractors are already quite familiar with the type of equipment and become proficient very quickly. And, even less experienced operators (like homeowners) can become comfortable running the equipment very quickly knowing the rental store will assist them in learning how to safely use the equipment.

    Schmidt says an important key to helping customers with rental equipment is setting them up with the appropriate machine for the job. Customers can waste money renting equipment that’s too large for their project, when actually a smaller unit is what suits the situation best.

    Compact excavator customers should consider the maximum digging depth before renting a machine. Rental customers may also want to evaluate the maximum reach, dump height and front swing radius, before finalizing any rental decision. For homeowners in particular, transport of the machine is important. Some non-contractors may not have vehicles large enough to haul bigger compact units, so it’s important to consult them on this.

    The Vermeer CX229 Compact Excavator — the unit that Schmidt purchased — is relatively new to the compact equipment scene. The underground construction and environmental product manufacturer recently introduced a new line of compact excavators — seven models ranging from the smallest 3307 lb CX216 to the largest 11023 lb CX254.

    Before starting any underground project, contractors should contact the appropriate “one call” for locating underground utilities. Whether it’s a commercial or residential project, this is one task that shouldn’t be overlooked before starting a project.

    Benefits of the Compact Excavators
    Compact excavators have become increasingly popular when working in urban areas where space is limited and larger pieces of equipment can’t get into the confined quarters, says the American Rental Association. Many of the small excavators on the market offer customers the following benefits:

    • Zero-tail-swing clearance, allowing the operator to turn the machine within the stance and not swinging wide, beyond the track (Vermeer offers one zero-tail-swing unit).
    • Offer a solid foundation when working in softer underground conditions
    • Lightweight and easy to transport on a trailer
    • Equipped to handle a variety of attachments

    Even though the construction market has been tight around Decatur, rental of the compact excavator has remained constant, according to Schmidt. He says the rental business has been relatively flat when compared to previous years, but he and his staff of three are making a go of it still.

    Looking Ahead
    A member of the American Rental Association (ARA) and the Cornbelt Rental Association, Schmidt says that he focuses his business efforts on retaining current customers and keeping his fleet of rental equipment in top shape. An upbeat Schmidt remains positive about the rental market and says he anticipates growing his existing business through deliberate efforts.

    http://www.vermeer.com/vcom/CompactEquipment/Index.jsp?NewsID=10794

    A brace of Bobcat compact excavators released

    Filed under: Compact Excavators

    Bobcat Australia has extended its line of compact excavators with the introduction of the new 334 D series, a long-arm version of the 331 D series, and the powerful 341 D series.

    Bobcat Australia’s Bernard Sheary told Australian Mining that the 334 D series would be particularly suitable for stockpiling, grounds cleaning, and detailed excavation and drainage on mine sites.

    Its longer arm increases dig depth by 302mm, boom dump height is increased by 181mm and maximum reach at ground level is increased by 193mm. Its exclusive X-Change mounting system also allows easy exchange between attachments.

    With simular dimensions to the 331 D, the 334 D offers improved auxiliary hydraulics, an easy-to-change hydraulic control pattern, new instrumentation and electronics as well as better service access.

    The 334 D offers god operator comfort with optional factory installed cab heater and air conditioning, an adjustable suspension seat and a cabin that offers a much quieter working environment.

    341 D series

    The powerful new 341 D series compact excavator features a longer dipper arm and additional rear counter weight, giving it greater reach and better loading and digging depth.

    The longer Dipper Arm increases dig depth by 300mm, boom dump height is increased by 263mm and maximum reach at ground level is increased by 394.5mm. Even though the 341 D has greater reach, and digging depth it still has the same bucket digging force as the 337 D Series.

    The 341 D allows operators to do more digging, or truck loading from one spot.

    http://www.ferret.com.au/articles/30/0c018930.asp

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