Pentin Paja Oy

As simple as it gets – new Naarva S23C harvester head for tractors and small excavators

In the fall 2012 Pentin Paja Oy released Naarva S23 harvester head. The only harvester in the world that could cut, delimb and split the tree into firewood, directly after felling and without electricity. Now the harvester head is also available with Ø30 cm saw cutting. Naarva S23C is the only saw cutting harvester head in the world that can cut and delimb trees without electricity. It is mounted to the place of a loading grapple and requires no extra hydraulics or electricity.

Operation of S23C harvesting head is based on pressure-controlled valves. Grapple close-button closes the grippers. When grapple-close button is kept pressed, pressure rises and pressure-controlled valves release oil flow to the delimbing stroke cylinder. After delimbing you can reverse by pressing grapple open-button. If you want to cut the tree, keep grapple close-button pressed, pressure rises and oil flow is guided to the cutting unit. S23C delimbs the tree 0,5 meters per stroke. This means six delimbing strokes to make a three meter tree trunk.

S23C stays upright because of center of gravity. When you grab a tree and pressure rises, delimbing head starts to move. Delimbing head hits the tilt body and locks against it firmly. After cutting you can choose the direction for felling, because the tree stays upright. When you press grapple-open button the delimbing head reverses and the head is no longer locked in the upright position. Weight of the tree tilts the head to delimbing position. When you drop the tree, S23C returns to upright position because of center of gravity.

Structure of S23 and S23C is modular. The guillotine unit in Naarva S23 harvester can be replaced with a saw cutting unit. It is mounted to the same place and you only have to connect two hoses and bolts. Both S23 and S23C harvesting heads are lightweight and simple. S23C weighs only 240 kg and requires only 40 l / min oil flow.

Mounting S23C to a tractor is very easy. It goes straight to the place of the loading grapple, and uses the same two hydraulic hoses. S23C can also be installed to 5-8 ton excavators. For excavator installations we provide extension boom packages. They include an extension boom with 1,5 meter reach, quick coupler for the boom, rotator, link and all required hydraulics. S23C only requires one two-directional valve from the base machine.

Naarva S23C is suitable for first thinnings, energy wood harvesting, integrated harvesting and cutting Ø30 cm hard wood. Naarva S23C stroke harvesters have been exported to several countries this year: Sweden, Norway, Slovenia, Germany, Austria, Ireland and France.