Wednesday, November 15, 2006

Taking a cut at a new niche: Tigercat's newest log forwarders target cut-to-length forestry applications offshore

In the forestry industry there are two primary methods of tree hat, vesting; tree length and cut-to-length. In tree length harvesting, trees are cut, delimbed and hauled whole to mills, where the cut lengths are determined according to need and the appropriateness of a given cut on a given tree. In cut-to-length harvesting, the best cut length is predetermined by the harvester and the trees are cut to specific log lengths. These are then transported to separate mills that specialize in the processing of each length.

The method a forest manager uses for harvesting tends to be determined by region. North America mainly uses the tree length method while European harvesters trend toward cut-to-length. While Canadian forestry equipment manufacturer Tigercat has targeted its line of feller bunchers, skidders, loaders, harvesters and attachments toward tree length applications, the company is targeting Europe and select cut harvesters in the U.S. and Canada with its newest line of forwarders.

In cut-to-length cutting, Jon Cooper, Tigercat product manager, forwarders and wheel harvesters said, "forwarders are used to transport logs from the stump where they've been cut by the harvester to the roadside. forwarder comes behind a harvester and selects out all the common sizes of wood and loads them on the bunks in the back. The logs are then transported to the roadside where all the common pieces are put in common piles. You can elm up with as many as 13 or more different piles of wood at the roadside waiting for trucks from various mills to pick up their specific wood."

Tigercat, which introduced its first 1018A forwarder in 2000, now has three classes of machines available. Since that initial introduction, Tigercat has launched the IS-ton 1065, followed by the 20-ton 1075, a replacement to its original 1018A machine and later the 14-ton 1055.

"The 1065 was designed to be a heavy-duty, middle class size forwarder," said Cooper. "After we designed it, built it and got it out in the field, it was very well received and we went into production very quickly.

"We then created the 1075 to replace the 1018A. The 1075 is basically an upscale 1065. It shares the same flame, same engine, same hydraulics --everything is the same but with a higher capacity drivetrain. The engine output is increased from 228 hp to 241 hp."

Then, Cooper said, the 1055 was added for people who want to do select harvesting. "To do that, you need a relatively small machine and at a 14-ton payload capacity, the 1055 fits the bill."

In developing the forwarder line, Tigercat focused on using parts commonality throughout the line, powering all three models with Mercedes-Benz 906 diesel engines rated 201, 228 and 241 hp at 2200 rpm. The inline 906 has six cylinders, a 6.37 L displacement and is mated with an AKG radiator and side-by-side oil cooler.

A hydrostatic transmission drives the machines' ground drive system, incorporating stacked Linde pumps mounted at the back of the engine. The bi-directional pumps drive Linde hydraulic motors that are driven through a transfer case, powering two speed ranges up to 15 mph.

Each wheel of the eight-wheel-drive forwarders are fitted with NAF planetary drives, driven thorough the bogie axle housing by a differential gear set driven off the transmission driveshaft. This driveline package uses NAF bogie axles, NAF oil-cooled brakes and NAF independent differential locks. Nokian and Firestone tires round out the powertrain assembly.

The rear of each forwarder is equipped with a Cranab or Loglift crane and Hultdins grapple attachment to maneuver logs to and from the 45.2 to 65 sq.ft. rear load bunk. The hydraulic cranes are powered off the Linde pump circuit using Parker control valves and Tigercat cylinders in the center articulation joint. Lift torque for the three forwarders is 77,450, 77,443 and 111,350 lb.ft., respectively, the company said.

Because of the harsh forestry conditions the 1055, 1065 and 1075 forwarders endure, the operator cab is constructed with a steel structure featuring two exits, air conditioning and heat. All monitoring and display functions are available through a Parker Hannifin IQAN system, which incorporates an easy-to-read LCD display. The operator compartment also includes Parker joysticks and an air ride seat.

No comments: