March 2007 - The Logging and Sawmilling Journal
A SIMPLE SOLUTION
By Jim Stirling
Wet snowflakes the size of dimes swirled from a gloomy sky. But the smiles were broad and sunny from those watching the Valmet clambunk deposit its load at roadside.
The machine’s overall performance was impressive but the way it was unloaded drew the extra plaudits. Key to that is a unique custom-made and designed attachment located behind the operator’s cab. When activated, it rises from its rest position to meet and direct butts on the load of tree-length logs out from the clambunk in a single, easy motion. “We call it the pusher thing,” says Gib Randall with a smile.
Randall is partner with Eli Hetu in Amboy Logging Ltd, a log contracting and roadbuilding business based in Quesnel, British Columbia. Amboy is a long time contractor for West Fraser Timber and is harvesting around 225,000 cubic metres annually.
Randall’s “pusher thing” is the culmination of a vision. Making it a reality came through a rare level of teamwork between Amboy and Valmet dealer Coneco/ Terratech, which supplied the engineering and fabrication for the pusher in its Prince George shop.
One of the issues with clambunks has been the unloading, especially in adverse grades. Top layers of logs had to be cherry-picked off before the machine acted like a conventional skidder in releasing its load. “So much time was spent in off-loading and trees getting hung up,” explains Randall. He knew there had to be a faster and more efficient way. The pusher is it.
Amboy’s simple yet ingenious solution has other advantages beyond faster turnaround times. “It’s way easier on the crane. In fact, it’s way easier on the whole machine,” says Randall. “It works good and the guys like it.” The pusher is activated by simply pressing a button in the operator’s cab. Amboy has also installed a pusher on its trusty older Timberjack clambunk skidder.
When the Amboy partners took their pusher concept to Terratech (now part of Coneco), their specialists accepted the challenge and ran with it. The pusher took 13 sometimes l-o n-g days to produce from shop to bush. Terratech’s forestry consultant and equipment training expert Peter Sirfalk worked closely with Amboy on the design and engineering. Terratech’s Bernie Hamilton did the hands-on manufacturing and fabrication.
Amboy’s Swedish-built Valmet 890.2 is actually two machines in one. Sirfalk says you can pull the pin, put the forwarder bunks on and voila, the clambunk skidder is now a forwarder.
It’s not quite as simple as that, of course. It takes about 3.5 hours to do the conversion in the comfort of the shop with all the necessary tools readily at hand. Call it six plus hours in the field, depending on bush conditions. The time will be reduced with familiarity. But the flexibility is a huge plus. For example, if the mill decides it wants short wood, the Valmet can operate in forwarder mode.
The clambunk/forwarder combination represents a second machine for a single investment and comes with an accented value in a resale situation, adds Sirfalk. “In the Valmet 890, you also have a very reliable machine that uses lots of components that are readily available around the world,” continues Sirfalk “It’s built to work and to be productive.”
Valmet’s Sisu engine generates 230 horsepower, giving the 890 all the power it needs, he adds. Sirfalk says in some ways the machine might be described as over-designed. But one of the positive sides of that is that it has very few maintenance requirements. And routine procedures are simplified.
A single central location accesses six grease nipples, for example, and oil levels can be checked without lifting the heavy engine hood cover.
Amboy has long recognized the forwarder concept and Randall and Hetu have bought heavily into the forwarder/ clambunk system. Harvesting plans, block layout and falling phases are all predicated on how the felled wood will be moved.
Randall is pleased the way the Valmet 890.2 has performed in the bush. “We’ve had it about a year now and had very few problems with it, nothing heavy yet,” he reports.
As the Valmet operator builds a load, the tree-length wood is carried high in the clambunk. “More of the logs are off the ground and less dragging out the back and that’s an assist for skidding on soft ground. You’re not repeatedly beating the ground to death,” points out Randall.
There’s less breakage, too, he notes. Waste reduction is increasingly important in lodgepole pine as trees killed or infested by the mountain pine beetle epidemic become dessicated and more vulnerable to breakage.
The Valmet’s load capacity is a function of piece size. It averages 25 to 30 cubic metres a drag, or perhaps a lift is a more appropriate word with the Valmet.
It was recently working in better-thanaverage size wood on a block southeast of Quesnel. That’s unusual for Amboy, which has traditionally been the go-to contractor for steeper and more rugged ground.
Forwarding distances were up to 500 metres: Randall and Hetu had diverted the Valmet from a closer on-block road.
A surge of warm weather was forecast which, if it materialized, would turn the clay sub-soil on the closer road into a mess and slow down production. Utilizing the forwarder/clambunk system usually translates to covering more ground to deliver fibre to roadside for processing and building fewer on-block roads.
The Valmet 890 is surprisingly miserly on fuel consumption, averaging 160 litres a day. Rising fuel prices are predicted to continue, although they are still considerably cheaper in Canada than in other parts of the world. The clambunk also helps build more uniform decks at roadside to facilitate the processor operators. And in large part, credit for the success of that also comes down to Amboy’s pusher thing.
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Monday, August 06, 2007