CHARACTERISTICS AND DEVELOPMENT OF THE CONSTRUCTION OF LOGGING HARVESTER HEADS

Abstract

One of the main components of multioperating harvesters is the cutting system, aggregated with the base machine as a harvester head. The constructional and operational harvester head parameters impact the productivity, quality and accuracy of wood harvesting.This paper presents the description, characteristics and classification of multioperating forest machine heads, and most of all the constructional changes that took place over several years of use in forestry harvesting. The changes are based on an analysis of selected manufacturers of heads including most Scandinavian companies as well as John Deere, Timberjack, and Ko-matsu (Valmet). Cutting components compared with bar and chain, hydraulic motor heads, feed systems with rollers, measurement timber systems and knife delimbing systems are compared. In addition, we analyse the changes in the basic parameters characterizing the harvester head, its dimensions, weight, maximum felling diameter, saw length, delimbing speed and diameter of branches pruning. The summary also outlines changes in the trends in harvester head construction.