This is the largest two-wheel head in the S-series.
The Komatsu S172 is designed for Komatsu Forest’s largest harvester, the Komatsu 951, and is the heaviest head that can be delivered together with a 10-metre crane. Head weight starts at 1,675 kg (3,693 lb). The head has been designed for harvesting large diameter trees. Delimbing takes place using three hydraulically controlled delimbing knives and a fourth, moving vertical knife. The head uses Flex Friction Control, which allows the stem's position in the feed path to be regulated by a sensor in the vertical knife. This results in lower friction with the stem without sacrificing delimbing quality.
The feed system uses two feed rollers that can handle large trees. The motor design allows increased force with larger trees, whereby when feeding the tree; the motors slow down in order to deliver more power. If less force is required to feed a tree, then the motors speed up. Komatsu have focussed on ensuring that the head is robust through design aspects such as using a high-strength steel frame to protect head components. The head is fitted with protected hose routing to limit downtime. The head is equipped with ORFS couplings to minimise hydraulic oil leakage. However, maintenance is still simplified through good access to service points, the valve block and other vital components. Different options and customisation can be applied to measurement, feed rollers and saw units to colour marking and stump treatment. The Komatsu S172 will go into production in June 2015. Source: http://www.komatsuforest.com/default.aspx?id=1848&newsid=142376