Performance, Capability and Costs of Small-Scale Cable Yarding Technology

Abstract

The authors tested two mini-yarders, one for uphill and the other for downhill extraction. The two machines were modern commercial models, offering state-of-the-art yarding technology on a miniature scale and at a much lower cost than required for purchasing a full-size tower yarder. The two units must not be regarded as alternative, but rather as complementary, since they offer different capabilities and advantages. Both machines were tested while harvesting firewood from the thinning of young beech stands in Central Italy. The tests indicated that both units can reach a productivity between 1.5 and 2.4 m 3 SMH -1 , including all delays, as well as set-up and dismantle time. Calculated extraction cost ranged between 24 and over 30€ m -3 . The authors calculated a set of regression equations for estimating machine productivity as a function of the main work conditions. The performance of the studied mini-yarders does not seem much inferior to that achieved by professional light tower yarder under the same work conditions, but the lighter construction of the small-scale units may result in a lower resistance to wear and abuse. In any case, mini-yarders seem ideal for deployment under the typical conditions of small-scale forestry, offering a good solution to wood extraction on steep terrain, competitive with animal and winch logging in terms of productivity, cost and operator comfort. R. Spinelli (&) CNR, Timber and Tree Institute,

Time consumption and productivity of a medium size mobile tower yarder in downhill and uphill configurations: a case study in Czech Republic

“…The utilisation rates determined by this study are not much different than those reported by Spinelli et al (2010) in Italy for two tower yarder models and in Turkey by Ozturk and Senturk (2006) for uphill and downhill extraction of spruce timber. The test of the cable crane obtained satisfactory results but a number of organisational features could be improved in order to fully exploit its potential.…”

“…Technical characteristics of the cable crane. Similar to other studies to determine the performance and cost of cable yarding technology, this study analysed time consumption data using the general concepts employed in observational modelling studies (Aykut, 1986;Zimbalatti and Proto, 2009;Spinelli et al, 2010;Borz et al, 2014). The time and motion study was conducted using the repetition timing method to determine the total yarding cycle time, i.e., the amount of time required for the carriage to travel from the landing until the unhooking of the payload.…”

Productivity and cost of biomass harvesting for energy production in coppice natural stands of Quercus pyrenaica Willd. in central Spain

“…The productivity was greater than what could be considered, varied between 1.4 and 2.6 m 3 per scheduled time. This logging system reached competitive operating cost compared to other logging system [21].…”

“…According to the RE National Action Plan 2011e2020 [4], renewable energies accounted for 9.4% of primary energy consumption in 2010, 132,000 Mtep, whereas the goal for 2020 is 20.1%. Regarding electricity production, RE accounted for 24% of total Spanish electricity (21,410 Mtep) production in 2010, whereas the objective for 2020 is to reach a 36% contribution. Similarly, biomass and biogas are intended to grow at a yearly rate between 7.0% and 12.6% during the period 2009e2020.…”

“…They reported more costeffectiveness using tractor for logging instead of mule pack in Turkey oak stands. In Italy, cable yarding have been used to haul firewood off from coppices of Quercus cerris, oak, holm oak and beech stands [20,21]. The productivity was greater than what could be considered, varied between 1.4 and 2.6 m 3 per scheduled time.…”