Held in Sweden June 4-7, Elmia Wood drew more than 50,000 visitors from 52 countries.

Copyright 1997. Contact publisher for permission to use.

Caterpillar Unveils Skogsjan Line

Making its first appearance ever at Elmia, Caterpillar did it with a splash, displaying 17 machines in concert with its Swedish dealer, Engson. Cat's participation at Elmia was much anticipated following its purchase earlier in the year of majority interest in financially plagued Skogsjan AB, a Swedish-based pioneering manufacturer of cut-to-length equipment.

Elmia officials described the move by Cat as an international breakthrough for Scandinavian-style harvesting machines. Caterpillar, acknowledging the growing importance of cut-to-length technology in the $4-billion forestry equipment market, has to this point announced dealer arrangements for Skogsjan products in Sweden, Norway and Finland. The Skogsjan line, redesigned and now utilizing Cat engines, encompasses harvesters, forwarders and harvesting heads.

Twelve Skogsjan machines at Elmia included the first world appearance of the 487 and 695 harvesters in four- and six-wheel configurations. The machines, representing the smallest and the largest in the four-model harvester family, are powered by Cat's 3126 diesel, rated at 163 hp in the 487, and 221 hp in the 695. Cat has boosted hydraulic capacity to enable the head to handle big trees while the harvester is moving. The machines feature a pendulum boom and individually adjustable wheels or bogies, thanks to a fully hydraulic suspension system. The operator selects height and level, and the machine adjusts automatically for obstacles up to 16". The operator can manually compensate for slopes up to 15� fore and aft, 25� side to side, and for obstacles up to 6' in height. Cat describes the Skogsjan 1800 and 2200 knuckleboom cranes as the strongest in the industry.

The Skogsjan 645, 655, 665 and 675 harvesting heads, all single grip (it isn't thought that the double grip will be around much longer and in fact there was only one at the show), encompass cutting diameters from 17" to 23". The heads are designed for applications ranging from thinning to clear-cutting.

The three models in the low-ground-pressure, eight-wheel Skogsjan 1088 forwarding line span load capacities from 22,000 lbs. to 30,800 lbs.

World Debut For Timberjack 1710

Marking its 50th anniversary, Timbjerjack used Elmia for the world debut of its 1710 forwarder and - easily the most eye-catching machine at the show - a three-day walkabout for the world's first walking harvester.

Also on display were the new 850 feller buncher (see article on this machine elsewhere in this issue), a new 460 grapple skidder and the company's updated B-Series 870 and 1270 harvesters.

The six-wheel 1710 has a 17-tonne load capacity. The new heavy-duty forwarder is powered by a six-cylinder Perkins 1306-8T1 turbo-charged engine rated at 210 hp. The machine features a fully hydrostatic transmission, bogie axles, and the new F111 grapple crane that offers an 8.5m reach.

The attention-grabbing walking harvester, a concept machine introduced as a prototype in 1995, was developed by Plustch Oy of Finland, currently a Timberjack affiliate. It was designed as a ground-friendly harvester on steep slopes and soft terrain where other machines can't operate. The machine walks at a normal walking speed using six legs. Depending on the terrain, it can also move and maintain its balance and low ground pressure on three to five legs. A highly advanced control system, onboard computers and sensors can adjust the steps according to the roughness or steepness of the terrain. It can clear obstacles up to 120 cm. One joystick steers the machine and controls speed.

The walking harvester is not commercially available, but Timberjack says it will continue R&D on walking technology as part of an ongoing effort to develop forest-friendly harvesting equipment. The development project is being carried out in Tampere, Finland.

New Valmet 921

Valmet also unveiled its completely new 921 harvester, larger than the 911 and of interest to Canadian contractors looking for a heavier cut-to-length machine with better clearance and more power. The 921 is the same width as the 911 but it is longer (7315 cm), clearance has been increased to 67 cm beneath both the frame and the axles, and, at 18 tonnes, is quite a bit heavier. Paired with the Valmet 965 single-grip head it can handle trees to 65-cm butt diameter.

The 921 is powered by Valmet's newly developed 634 engine, a 7.4-litre turbo diesel rated at a peak 2,101 hp; normal operating speed is 1,500. The engine is designed for high output and torque - pulling power is 14 tonnes. Hydraulic capacity has been boosted against the 911 (to 280 l/min.), braking force is better, and the cooling system capacity is significantly larger.

The Cranab 1600 (16.5 tonne/metre) has been beefed up considerably compared to the 1400 used with the 911. Retraction and extension force are between 15 per cent and 25 per cent greater. The 921 has an automatic self-levelling cab which has been enlarged. Valmet has improved the suspension to reduce vibration and operator fatigue. The 921 shares a number of major components with the 890 forwarder, including the gear box, computer-controlled transmission, and bogie gear casing.

Pika Combines Harvesting, Forwarding In One Machine

Pika has an interesting machine that a lot of people think will be more widely seen in the near future. In fact, Pika calls it the machine of the future.

The company has mated its 728T forwarder (153 hp, eight-wheel drive, 12-tonne load capacity) with a Pika 300 'harvestergrapple' - a combination harvesting head and grapple.

The resulting harvester-forwarder (many people are calling this concept machine the 'harwarder') can handle both functions in small thinning stands - cutting the stem and placing it in the forwarder bunk before moving to the next tree.

Pika's take on this concept has resulted in some very interesting design features, one being that the 300 single-grip head is completely hydraulic - it is controlled with a patented hydraulic logistic valve. As there are no electric valves in the head, there is no requirement to run electric cables back to the carrier. When switching a 728T grapple for the 300, only one extra hydraulic hose (1/4") is required. The hoses for the rotator are enlarged to 3/4".

Another interesting aspect of this head is the location of the feed rollers inside the grapple arms.

Also notable is that the loader crane (a Loglift 71FT100 with a 10m reach is recommended) reaches over the cab during harvesting, meaning the operator is working in front of the machine. Visibility is excellent, an argument against past 'harwarder' concept units.

The operation of the harvester has been made as easy as possible. The loader control is the same as in a normal forwarder. Feeding, reversing, cutting and delimbing are controlled with individual switches by pressing each switch as long as that operation stage requires. The harvester goes automatically in an upright position when the grapples are opened, and goes into a floating position when the grapples close with adjusted power.

The Pika 300 head has a felling diameter of 35 cm and delimbing diameter of 30 cm.

Eco-Mate Rethinks Hydraulic System

Lars Bruun, well known in Europe for innovative forestry machine concepts, has come up with a different take on the conventional hydraulic system. The Eco-Mate system involves adding energy-saving cylinders to the crane of a harvester or forwarder. Attractive in its simplicity, the system stores energy that is released while the crane is being lowered, then releases that saved energy to supplement the machine's load-sensing hydraulics during the next phase of the working operation.

The machine has been field-tested in Germany on a Timberjack 1270 harvester and, according to the company, fuel savings have been almost 20 per cent. Other benefits are reduced noise and a lower hydraulic oil temperature (10� to 30� lower). Final evaluation of the concept has yet to be completed.

Advanced Virtual Reality Training Simulators

Valmet and Timberjack demonstrated advanced virtual reality harvester operator training simulators, and both drew considerable attention. The Valmet harvester simulator, which the company describes as more advanced than an aircraft simulator, was developed in a unique working co-operation with Vancouver-based Lateral Logics.