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Tech Update - Skidders
The Tigercat 610C is a versatile mid-sized skidder best suited to thinning and final fell applications in plantations and specialty selective felling in natural stands. The 620D, 630D and 635D models are all available with the largest capacity grapples and widest tip-to-tip openings in their respective size classes, says Tigercat.
Refinements made to the hydrostatic driveline enable improved performance and fuel economy. The next generation IQAN control system has improved functionality and provides a simpler, more intuitive user interface. The arch has been redesigned for improved visibility, more powerful arch holding force and quicker cycle time.
Inside the cab, the D-series skidders are equipped with Turnaround—the revolutionary rotating seat, which has a two-position mechanical lock and provides full rear-facing drive capability and control of all functions. The steering wheel was replaced with an armrest-mounted joystick for improved ergonomics. Drive pedals are located at both the front and rear of the cab.
Combined with Tigercat’s hydrostatic driveline, Turnaround allows the operator to travel in reverse while comfortably facing the rear. The full speed range is available, whether in forward or reverse.
Turnaround is also useful for picking up double bunches, loading the grapple with roadside debris and angling and placing the load optimally for the processors at roadside.
The 620D and 630D are suited to the majority of high production skidding applications while the six-wheel drive 635D with its long wheelbase, low-ground and massive grapple is designed for long hauls, extremely heavy loads and very soft or steep terrain.
KMC offers a different design for different results. The unique design of its track skidders features balanced weight distribution, individual roadwheels that come with torsion bar suspension and rubber bushed 22” wide steel track pads. This allows the KMC tracked skidder to work on steep slopes, wet/boggy ground or environmentally sensitive soils where other ground based machines cannot.
The KMC track skidders can work safely on slopes up to 50 per cent favorable and 40 per cent adverse. They can also work in wet/boggy soils with minimal site degradation compared to rubber-tired skidders or crawler tractors.
The torsion bar suspension and 22” rubber bushed steel track can follow the contour of the terrain, keeping more track on the ground, thus resulting in lower ground pressure, less soil compaction, better traction/less track slippage and minimum rutting or soil displacement.
The 1000 Series track skidder can have either a mechanical or hydrostatic track drive and can be equipped with a choker arch, arch grapple or swing grapple attachment.
Caterpillar Forest Products
Cat wheel skidders are workhorses with the strength and power to handle a heavy bunching grapple with a full load of logs.
The Cat C-Series wheel skidder’s five-speed transmission matches engine power to the load size and ground conditions. A lock-up clutch torque converter gives the C-Series all the advantages of torque converter operation along with the speed and fuel efficiency of direct drive. Travel speeds can be as much as 15 per cent higher with the lock-up clutch engaged. Cat bunching grapples feature a strong box-section design and higher clamping forces for faster log loading and excellent retention. The “Auto-Grab” grapple hydraulic system monitors and adjusts tong pressure as needed to maintain a secure grip on grapple loads without wasting power. Cat track skidders deliver the balance and power needed for safe and productive skidding in steep or poor ground conditions. The skidders are available in a variety of track and grapple or cable configurations.
The John Deere 848H skidder is built to handle all types of wood in any terrain, providing high productivity and fuel savings.
It features an exclusive lock-up torque converter, which stays engaged between gearshifts. This attribute significantly improves fuel efficiency and productivity, offering a smooth, steady shift. When locked up, the skidder has the efficiency of a direct drive. The Powershift torque converter transmission uses Smart-Shift technology to continuously evaluate speed and load conditions, and adjusts the machine to suit.
A fuel-efficient Tier III PowerTech Plus engine delivers power in all conditions. It has a long wheelbase, wide stance and
The high-capacity-grapple option with 18-square-foot area and 134” tong opening means fewer trips over the skid trail to get the logs out.
Standard on the 848H are SWEDA Plus, super-wide extreme-duty axles.
The 848H also features the Smart Cooling system, which is a hydraulically driven variable-speed fan that runs only as needed to keep the machine at optimum temperature, while reducing noise, fuel consumption and operating costs.
The design of several components provides ease of maintenance, including remote-mounted engine, hydraulic, and transmission filters that are positioned for easy access and the easy-to-reach swing-out side-by-side cooler and radiator.
Awassos manufactures a compact wheeled skidder, the MD-80, which is designed to provide maximum flexibility. It is available in cable skidder and grapple skidder configurations. There is also the standard and biomass grapple options, as well as single or dual function grapple boom.
A remote control is standard in the cable skidder version and optional in the grapple version. The different tool options are removable and interchangeable; with one vehicle, it is possible to have all the different skidder configurations available. The optional hitch point gives the possibility to have a log trailer hauled and controlled with the skidder. New options will be available soon for even more flexibility.
With its 7’ wide configuration, it performs best in selective cuts. At 10,500 lbs, this is an easy to transport skidder with low ground disturbance. Designed for 84 hp, it is possible to lower the horsepower for better fuel efficiency.
Designed and manufactured in Canada, the Tanguay TG88E is by far the largest track grapple skidder in the world.
Powered by a 400 hp QSM11 Cummins engine, the eight-wheel-drive TG88E is used mainly as a low ground pressure clambunk or grapple skidder with a payload capacity of 35 tons.
The TG88 is the Canadian solution for forwarding large volumes of timber on long distances in the northern boreal forest of James Bay in Quebec. The Tanguay TG88E has also been very successful in tropical Australia’s plantations in the soft and sensitive soil of Queensland and steep slopes of the Gippsland Mountain in the State of Victoria.
The 100 per cent hydrostatic drive provides 146,000 lbs of drawbar pull. Developed 20 years ago, the TG88E’s innovative traction provides the manoeuvrability of a small four wheel forwarder and low ground pressure for minimum ground disturbance.
The Oxtrac is a unique skidder whose small size and low ground impact allow logging contractors to have access to wood lots that are not physically accessible and/or financially viable to log using standard skidding equipment.
Unique and co-friendly, the Oxtrac is ideal for less intrusive practices such as urban logging and selective tree harvesting. Its low ground impact makes it the machine of choice where terrain is sensitive.
The Oxtrac features low fuel consumption and low noise emissions coupled with its raw power.
Versatile, the hydraulic front and back connections on the Oxtrac allow owners to add various quick-attach accessories, including a log splitter, brush mower, snow blower, grapple, etc.
A friend of parks and sanctuaries where dangerous or damaged trees must be removed, the Oxtrac is the ideal machine to harvest mature trees without damaging juvenile and adult trees.
The TimberPro clambunk will more than double the production of a large four wheel grapple skidder when the skid distance stretches out beyond a quarter of a mile, says the company.
Another advantage is always being able to maximize the load with the self-loading boom and being able to load trucks by drag loading as is often done in the U.S. South.
In other applications, a cutting attachment can be installed on the boom to cut and skid with the one machine.
The machine is equipped with heavy duty bogie axles and is powered by a 300 hp Cummins engine. The cab rotates 360 degrees with excellent access for working over the front with no power plant obstructing the view. Maintenance is made more efficient with gullwing access to most major components. If skidding distance is a problem, the TimberPro clambunk will help solve that problem.
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