An Operator's Dream
Harvesting and Felling Heads
Compiled By Mel-Lynda Andersen
This system eliminates the need for a soft clamp function. A cushioned-ball butt plate design uses rubber ball dampeners to cushion the shock exerted through the butt plate, thereby reducing the strength on the frame and other sub-structures. A compact hydraulic system also sits well protected on top of the frame for servicing accessibility.
Three different styles of feed rollers are available to suit all applications: rubber tires with chains, solid steel rollers with spikes and a third patented roller design for sensi-tive sorts, consisting of individual rubber-mounted steel grip sections. According to the manufacturer, these sections are long-wearing, inexpensive to replace and their rubber mounted design provides more sur-face contact and increased delimbing power with less damage to the trees.
Pierces new model HTH16-840 Pan features a patented sectioned feed roll design, as well as a patented automatic delimb arm positioning system, compact hydraulics, and a fully automated Logmate measuring system with 20 pre-programmable presets. Pierce also m a nu fa c t u re rs the HTH18 LogMax, a Scandinavian-style harvester head with variable displacement feed roller motors, the HTH 20 Harvester and the HTH 26 Bigwood Harvester.
The operator can select a variety of lengths and can process trees auto-matically while loading a forwarder. Production capacity is 5 to 7 CDS/hr. behind a feller buncher and 3 to 5 CDS/hr. processing at the stump. The Inchworm can be installed or removed from the carrier in a half hour.
Forest Technology (Fortec)
The controlled felling design of the 1850-TS allows the operator to place the tree where desired for processing, increasing skidder efficiency. All hydraulic valving is located on the processor, reducing the number of hydraulic lines running to the head, and minimizing their required maintenance. Rugged structural components are designed for durability and longer machine life. New options for the 1850 Series include lower arms and a roller drive system. According to Fortec, the 1850 or any of the processors in its growing product line can be configured to match site-specific applications.
The Koehring 18'' sawhead, for boom-through felling with smaller knuckle-boom tracked carriers, is effective in small to medium wood. The most popular sawheads in the companys lineup are the 20'' saw-heads, for all-around performance in both drive-through and boom-through felling, according to the manufacturer.
New to the lineup is the companys 24'' head, designed specifically for long stem control and boom-through felling of larger-diameter wood. Koehring offers two blade options: the new 4000NK (Narrow Kerf) blade and the 4000B (Full Kerf) blade. Both blades have full-thickness tooth-mounting lugs that require minimal maintenance.
Koehring Waterous harvesting heads fell, delimb, buck, top and pile in one continuous operation at the stump. They represent auto-mated delimbing and processing systems, producing logs to exact lengths. The 3,000-lb. 762B head mounts on carriers over 20 tonnes.
With its durable construction and easy servicing access, this unit is said to be well suited to cut-to-length harvesting. The 762B model weighs 2,200 lbs. and is mounted on carriers over 15 tonnes; it is primarily used for thinning and cutting in smaller timber.
Hahn Machinery Inc.
This full-featured harvesting head is priced well below competing models. Some of its features include fingertip processing con-trols, electronic length measuring system, 3/4'' pitch felling/bucking saw, two-speed roller feed, automatic saw oiler, and alloy steel construction. Aggressive roller design, large drive motors and four delimb knives ensure quality delimbing in tough conditions. Heavy-duty guards protect the operator while a high-capacity oil cooler and added filtration protect the Jubota hydraulic system. This head also offers two roller speeds, electronic log length measurement with two presets, and fingertip processing controls.
The new twin tower series offers the same features as the centre tower series (excluding tilt options); besides improved operator visibility, the manufacturers claim the portal design pro-vides maximum strength with a minimum of weight. The full-tilt options on the centre tower heads enable the operator to direct tree fall and bunch in all directions, in tight selec-tive cutting situations, during roadway cut-ting, and for laying matting material in sen-sitive or swampy conditions.
Because of its ability to make larger and fewer bunches at any angle from the trail, the full tilt minimizes damage to advanced growth and reduces feller buncher and skidder travel. Wide clamp arm spread and four independent clamp arm cylinders provide improved tree alignment and control, increased leverage, and reduced power loss from butt friction, according to the manufacturer.
At 2000 kg, the AFM Magnum is built for a 22- to 35-ton tracked excavator, and can fell and delimb stems ranging from 5 cm to 25 cm. Four separately controlled delimbing knives and three roller drivers provide feed speeds of up to 5 m per second. With the new patented AFM OptiCut sawing system, both the saw cover and the bar move according to the tree diam-eter into an optimal sawing position.
This system minimizes bar damage because felled trees never land on top of the bar; cut-ting is always done within the optimal cutting area. At 1150 kg, the AFM 60 can fell and delimb stems ranging from 5 cm to 60 cm. This head has a three-roller drive, as well as two optional hydraulically driven feeding rollers and one hydraulically driven track. A 15- to 25-ton excavator is the recommended base unit for this machine.
Both harvesting heads are available with steel or rubber rollers for softwood, or with eucalypt d eb a rking rollers. The Finnish Motomitt measuring and control system is equipped on all AFM saw heads, featuring automatic scaling, programmable and user-defined control and auxiliary keys, length and diameter calibration for every species, reporting capabilities, automatic colour marking and value scaling.
Fully open, the harvester head is only 120 cm wide, making it easy to place at the trunk base. Steel rollers or chain tracks can be fitted to the tandem feeding axles. Tandem axles and 24 KN feeding power enable delimbing of even twisted trunks. The head can be fitted with a three-or five-knife delimber. The maximum cutting diameter ranges from 52 cm to 64 cm.
The synchronization of the delimbing arms and the design of the feed roller system arms reduce the number of functions on the head. The delimbing arms reduce friction and are equipped with front and back knives that cut limbs growing in any direction. The front floating delimbing knife, combined with the delimber arms, surround the entire stem.
Three live feed rollers positioned in a triangular fashion on the DH550 provide better stem alignment and traction at a speed of up to 16' per second, according to the manufacturer. Two motors power the feed system: the first enhances speed and the sec-ond increases delimbing strength. The hydraulic system is integrated to the frame, simplifying installation on the carrier, and a high-performance chain saw with a saw stroke limiter ensure fast cuts and safe saw return, preventing bar bending. The Optilog system on the DH550 has been developed specifically for cut-to-length harvesting.
Ketos patented tracked feed system means no measuring wheel maintencance, which translates into improved production, according to the company. Single or double pre-cision- length measuring is another feature exclusive to Keto. Hakmet also boasts a sophisticated, easy-to-learn computer system with printer, 88 available presets, wheel or track length display, volume measuring, automatic and manual feeding and sawing, on-screen trouble shooting, and six onscreen languages. Optional two-wire con-trol system is also available.
This prototype harvester can stand upright to fell trees or lay down to harvest blowdown. It can also delimb felled trees, process trees to specified length and diameter, load log-hauling trucks and perform hoe chucking tasks. Other features of this 6,500-lb. head include 360� continuous rotation, two rotate motors and four process drive rollers , 10'/sec. process rate, Hultdins topping saw and a bl ow d ow n butt-saw.
Three head sizes are available: 16'', 20'' and 24''. The manufacturer announces future developments for this harvester head will include a quick-grab silvi rake, angle bucket attachments, clam bucket and clam rake attachments, pulp-wood grapple arms, and a two-speed feed rate.
Other features on this head include mechanisms that are totally enclosed for protection, easy-to-read troubleshooting inspection panels, a maintenance design that enables servicing to be completed by the operator, lockout on both roller and stroke, automatic tension on upper jaws to accommodate tree diameter differences, and large-diameter stump capability at low ground height.
This saw head is compatible with all boom-operated feller-type machines, both swing and stationary and comes with optional computerized rollers/counters, and rollers with or without stroke operations.
Operators can fell, delimb, buck, top and pile precisely mea-sured logs up to 60 cm (23'') in diameter in one continous operation. The head is matched to the Sisu Cranab 1400 two-stage 9.3-m (30') telescopic boom for final felling and thinning operations. The Valmet 960- II features a cam-curve feed-roller sus-pension system which produces delimbing performance of up to 13'/sec. The cam-curve design requires less horsepower, minimizes friction with the delimbing knives, creates less stress on the head, extends roller life and ensures a tight, continuous grip which eliminates slip and potential fibre damage.
Five geometrically shaped delimbing knives follow the tree. Head knives and a spring-action, length-measuring wheel make up the Valmet VMM 1000 measuring system. VMM allows the operator to gain the optimum yield from each tree or log. The system can be programmed to record and sort trees by species, length and diameter class, coordinating the needs of the mill with the harvesting site.
VMM also provides information on trouble shooting. The 960-II head operates with three common hydraulic cylinders, reducing the need for extra fittings, hoses and valves. A separate cylinder controls the saw bar. The automatic cutting control of the saw bar is synchro-nized with the feed-roller system to mini-mize potential damage to the saw bar. The saw blade retracts the instant the cut is complete, avoiding damage to the chain.
The full-tilt system also reduces feller- buncher travelling and increases stacking volumes by 50 to 150 per cent, allowing the skidder to be fully loaded every time it makes a trip. The tilt system also offers greater protection of the feller-buncher boom since torsion is controlled hydraulically, rather than mechanically.
The hydraulic motor on this head is also protected inside the saws drive system frame. The company claims the quality of its saw (1-3/4'' felling cuts) and the low cost of reve rs i ble teeth also contribute to reducing operating costs. A new hold-down arm system reduces equipment stress and prolongs the life of the arms.
The Pika 600 can be matched with either Timberjack or Timbco machines for productive cut-to-length harvesting. The Pika 455 is suitable for thinning younger stands with base machines weighing 30,000 lbs. or less. On all of the above-mentioned harvesters, electronic valve controls eliminate electromechanical relay switches. An onboard computer can be programmed for up to 73 log lengths and three diameter sorts, and an optional printer outputs cubic volumes, piece and species counts.
A saw limit switch returns the saw after each cut, extending bar and chain life, and a top/bottom grapple combination offers high grip strength during felling and excellent manoeuverability, says the company. Second Growth, Inc. also offers customized engineering solutions for unique requirements.
Standard features include automatice chain tension, 360� rack and pinion rotator, automatic hydraulic braking system for controlled head positioning, and a saw bar limiter which restricts bar travel to tree diameter. The 850 weighs 3,000 lbs. (1360 kg) and the smaller 560 weighs 1,200 lbs. (545 kg).
A ramp-up/ramp-down, computer-controlled hydraulic system provides soft starts and stops, resulting in less slippage, better accuracy, less system shock and longer hose life, according to Fabtek. Three measurement inputs allow the operator to select the best measurement option for wood size and con-ditions. The SG220 is fast, owner service-able and cheaper than its European counter-parts, says the company. Fabtek has also taken the best features of its two most popular four-roller processor heads and combined them in a new 18'' model.
This new controlled fell design head adds an independent measurement wheel and now gives up to four independent measurement inputs, including diameter. All sensors are interchangeable. The new Fabtek Series 2000 computer combined with the 3.3 version software provides accurate measurements. The series 2000 also has an optional independent keypad and display screen for the cab. As in the SG220, the operator can select the best measurement sensor for long-wood or short-wood processing.
Twin planetary drives facilitate mounting bracket rotation and total tree control off the stump. A circular topping saw has a 7'' cut capacity, while the chain saw bar has a 12'' cut capacity; the head is also equipped with a floating delimbing knife. The unit is also manufac-tured with optional picker, accumu l at e r and holding arms. Bracket styles include 30� lateral tilt or nontilt, and 240� control-lable dual-motor rotation.
A Computer Optimized Measuring System (COMS) has also been installed for accurate cut-to-length or random lengths. The Risley Models S1818/S1821 Slingshots are designed for hardwood and softwood and represent a new generation of feller bunchers and delimber proces-sors , says the company. The Slingshot harvesting head is a single-grip, stroke-type processor that combines felling, accumulating, bunching, delimbing and processign into one forest harvesting attachment.
A functional design has been incorporated with Risleys hydraulic technology to produce a machine that makes operation and measuring fast and simple, says the company. The 5,000-lb. Slingshot is completely compatible with a wide range of carriers; cut capacity is 18'', side rotation is 220�, and delimbing power is 12,000 ft. lbs. at 8' per second. The Rotosaw I-2026T is a high-torque circular saw with dual motors for high-torque cutting and a variable piston motor that allows complete carrier adaptibility. Tree capacity is rated at 26''.
With two accumulator arms for multi-tree production and arms and deck designed for maximum accumulating capacity, this head is simple to operate and is designed to add safety and effi-ciency to logging operations, says the company. With the patented Roto Cut feed system, blade rotatation occurs only during tree cutting, and cutting speed is regulated by cut difficulty to prevent blade stall.
This head weighs 7,500 lbs. and has a complete hydraulic package and two tilt cylinders that tilt at a 15� angle. A gear motor flow divider gives power to the rung, as well as distributing and regulating oil to the extend blade.
Oil bath saw drive bearings eliminate daily greasing, and a hydraulic brake stops the heads disc with 20 seconds of saw switch cut-off. With the 18'' unit, there is a 2:1 drive ratio for better speed and respeed times, according to the manufacturer. Overall weight for the 18'' model is 4,500 lbs.; for t he 22' ' model is 6,750 lbs. Backcut capacity for the 22'' head is 36'' and 32''for the 18'' unit. Blade speed is rated at 1,250 rpm.
It can also directly pile logs in consistent piles ahead of the processor, making it easier and quicker to process or forward to roadside or landing, says the company. The operator can also position the head to pick wind-fall and dead-fall trees. The company also says the 340� tilt high-speed feller buncher sawhead is more productive because it eliminates wasted time swinging one tree at a time.
The Lako 550 is a medium-sized harvesting head used for thinning and clear cutting of small-size timber. Hydraulic excavators or rubber-tired carriers between 10 and 20 tons with a min-imum 75kW/102-hp engine power are recommended for the 550. The smallest Lako 450 model is designed for commercial thin-nings. The Lako 750 is the companys newest, largest and most efficient harvesting head. It is designed for big timber and requires a carrier over 25 tons with an engine output of over 120 kW (163 hp). All Lako harvesting heads have been simply designed facilitate trouble-free maintenance, says the company. Modular part design and manufacture make serial fabrication eco-nomical and effective.
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