Forest Harvesting Equipment Research Articles

Productivity Analysis of Modified Farm Tractors in Forwarding Industrial Wood Products

Public demands for forest products and services have been increasing gradually in many countries all over the world. Among the forest products, mostly round woods are produced in Turkey due to high economic value. On the other hand, there is a significant increase in demand for industrial woods in the domestic market in recent years. The reason behind this increase is the need of domestic companies in the wood-based panel industry for a large amount of wood raw material. . Farm tractors are the most widely used forest machinery in the extraction of industrial wood in Turkey. Farm tractors can be effectively used in mechanized harvesting operations after receiving some modifications and additional attachments. The modified farm tractors are affordable machinery for small logging contractors since their initial purchasing costs and hourly operating costs are quite low comparing with the forest harvesting equipment (i.e. skidder, forwarder, cable yarder). In this study, productivity of a modified farm tractor was analyzed during forwarding of industrial wood products. The study was implemented in Pinus nigra stand located in (?) the city of Afyonkarahisar in Turkey. In the study, the effects of forwarding distance on productivity were evaluated using statistical analysis. The results indicated that the most time-consuming work stage was unloading the truck and piling the wood products at the landing area, followed by ( in terms of time-consumption) collecting woods and loading the tractor at the stump. The average productivity of the forwarding operation was 6.06 stere/h (stere is the amount of wood pile with the height, width, and depth of one meter). It was also found that the productivity of the forwarding was significantly affected by the forwarding distance.

Occupational Noise and Vibration Assessments in Forest Harvesting Equipment in North-eastern Brazil

Occupational hazards arising from physical agents present in wood harvesting equipment may cause irreversible damage to the health of exposed operators. Thus, the objective of this study was to quantify the noise and vibration levels emitted by three types of wood harvesting equipment (Feller-buncher, Harvester and Forwarder) in a forestry company in north-eastern Brazil during a workday. Noise measurements were performed with an equivalent noise level meter (audiodosimeter) at the workstation and compared with the limits set in NR-15. To evaluate the vibration was used a full cup gauge, which has a sensor called triaxial accelerometer (directions X, Y and Z), installed on the operator's seat. As a result, the average noise dose of all activities in the operation studied did not exceed the maximum allowable limit of 85 dB (A) for 8 hours of continuous work. The whole body vibration in all equipment was below the exposure level, however, some equipment obtained indexes slightly higher than the alert level, a fact that shows a higher accuracy in the equipment.

A context specific machine replacement model: a case study of forest harvesting equipment

ABSTRACTThere are a wide variety of machine replacement models available in the literature. However, we postulate that any model needs to be customized to account for the context in which machines are operated. The objective of this research was to adapt an existing machine replacement model for the case of forest harvesting contractors operating in remote areas, such as those found in Eastern Canada. First, a requirement analysis was conducted to identify the gap between published machine replacement models and managerial practices. Next, an existing model was customized to integrate the specific needs of harvesting contractors. More specifically, working capital, variable utilization, and a mix of capital and borrowed funds were factored into the model. The findings serve as a guideline for machine replacement and future research. The proposed model can serve as a valuable tool for practitioners to make optimal fixed asset management decisions.

Testing the Effects of Label Deterioration on the Legibility and Comprehensibility of Warnings

On-product warning signs and labels face a variety of potential sources of deterioration (e.g., abrasion, ultraviolet light, and exposure to chemicals). Reviews of the available literature have produced few references regarding the effects of this deterioration on the ability of warnings to communicate. The objective of this study was to provide an initial investigation into this void in the literature. Actual warnings used on forest-harvesting equipment were photographed and rated with respect to the intensity of degradation. These real-world labels were then tested for legibility and comprehensibility using a sample of undergraduate students. The results indicate that at moderate levels of label deterioration persons can often correctly comprehend the intended safety messages. With respect to a degradation intensity rating of 3 (on a 5–point scale), the number of participants that correctly identified the conceptual meaning of the warnings (82) considerably exceeded the number that correctly identified the entire set of text messages (53).

Physical effects of site disturbance on peatlands

Forest harvesting on peatland sites during the frost-free season often creates water-filled ruts and transfers more humified layers of peat to the surface. Foresters have generally assumed that such disturbance has negative consequences related to proliferation of graminoid vegetation, disruption of surface drainage leading to raised water tables and, possibly, reduced site productivity. An experiment was established during 1996 near Cochrane, Ontario to examine the physical impacts of site disturbance on peatlands. Summer traffic by forest harvesting equipment was imposed at three intensities on a Black Spruce–Speckled Alder site type. The fractional area of surface disturbance increased with the amount of traffic, but disturbance effects on the thickness of the aerated zone, depth to the water table, and microtopography were not significant. However, the consistency of the effects produced by the most intense disturbance treatment suggests that it reduced average elevations and aerobic layer thicknesses, and increased water levels, by 2 to 6 cm. The hydrological effect of site disturbance in this study was small compared with the typical effect of forest canopy removal on water levels. Key words: Forest harvesting; peat; peatlands; site disturbance; hydrology

Forest Harvesting Equipment Ownership and Operating Costs in 1984

Abstract Forest harvesting equipment purchase costs in 1984 were determined by a survey of equipment dealers and manufacturers operating in the South. Based on delivered purchase prices, fixed costs for equipment ownership were calculated using machine rate formulas. Equipment operating costs were estimated based on general guidelines, fuel consumption data, and historical records. The fixed and operating cost data can be used when considering equipment investments and analyzing actual or potential harvesting systems.

Failure Cause, Frequency, and Repair for Forest Harvesting Equipment

ABSTRACT TIME between failure and time to repair distributions for rubber-tired feller bunchers, rubber-tired grapple skidders, and mobile chippers are presented. There is a considerable amount of variability among machines of the same type. These differences indicate that a machine's availability is heavily dependent on its working environment, the operator, and maintenance practices. A tabulation of the reasons for failures is also given.

Computer Simulation of Forest Harvesting Systems, Development, and Application

ABSTRACT AS forest harvesting equipment becomes more expen-sive, short and long range planning becomes essen-tial. Computer simulation is a valuable planning tool. GPSS (General Purpose Simulation System) is a discrete event simulation language well suited to modeling forest harvesting systems and equipment. The main features of GPSS and development of a simulation model are presented. A whole tree harvesting system model has been developed using GPSS to estimate harvesting costs for many stand conditions in the Upper Peninsula of Michigan and northern Wisconsin. A simulation model for testing a prototype piece of equipment such as the topwood harvester makes it possible to obtain a realistic view of the true capability of such a machine.