Evaluation of Timber Extraction Machines in Turkey

In forestry, like every kind of production, product ion works require a productive power. This productive power can be provided by both human power or animal and machines which are used by human beings. The production of wood raw materia l are formed various stages that continues from the productive place to market center. These work s tages depend on each other like rings of a chain. Success and failures in each stage effect the next stage. However the increasing of forest product tha t is formed in our country recently, now hauling has bee n still made with old patterns, such as sliding, throwing, circling, transport with human, skidding with animals on direct ground. Besides special forest tractors and skylines are used in some areas . In this study researched technical features and w ork performances of MB Trac tractors and skylines in Tu rkey.


INTRODUCTION
The production of wood raw material are formed various stages that continues from the productive place to market center. These work stages depend on each other like rings of a chain. Success and failures in each stage effect the next stage. The transport of forestry products is realized in two stages. The first one is the primary transport stage which involves the haulage of timbers, while the second one is the secondary transport stage involving the main stage of transport of timbers, generally realized by trucks on forest roads [1]. However the increasing of forest products need that is formed in our country recently, now hauling has been still made with old patterns, such as sliding, throwing, circling, transport with human, skidding with animals on direct ground. Besides special forest tractors and skylines are used in some areas. The level of harvesting mechanization in developed countries is higher than Turkey. While mechanical harvesting is about percent 86 in Austria that is similar to Turkey, this ratio is about percent 9 in Turkey [2]. Protuctive forest are generally, found in mountainous areas which have %40 -80 gradient in Turkey. Timber haulage studies are usually practised with tractor winches that have double or single drums. Timbers are skidded directly on the surface with the shape of cable hauling by tractor winches. Another way of timber haulage is to benefit from skylines. Tractors are used in areas wich have % 30-55 slope gradient. But skylines are used in areas that have % 55-75 slope gradient [3]. Koller K300, URUS MIII and Gantner skylines are used in East Blacksea forest areas. Special forest tractors like MB Trac 800-900-1000-1100 and farm tractors. Like steyr 768, Ferguson are used in almost whole forest areas in Turkey.

MATERIALS AND METHODS
Turkey, with 97% of its land in Asia and 3% in Europe continents, is located between 42° 06' -35° 51' N latitude and 25° 40' -44° 48' E longitudes. Turkey is surrounded with the Mediterranean, the Black Sea, the Marmara and the Aegean Sea, has an area of 77 945 200 hectares [4]. As of the end of 2003, the total forest area in Turkey is 20 703 122 hectares. This figure is 26.6% of Turkey's area. High quality forests and coppice forests spread over 10 547 987 hectares account for 50.9% of the total forest area, coppice forests spread over 10 155 135 hectares account for 49.1% of the total forest area. According to 2003 figures, the percent of coniferous forest in the total forest area is 53.9 and that of deciduous forest is 46.1. Production capacities are approximately 12 039 718 m³/year in high quality forests and 8 837 705 m³/year in coppice forests, respectively [5][6]. Overall ratio of mechanization is relatively low. Approximately percentage of man power, animal power, machine power and skyline harvesting are 72%, 15%, 8% and 5%, respectively. The need for forest roads in total in Turkey was 201810 km and that 133693 km portion on which, corresponding to 66.25% constructed by end of 2002. Mechanical park at Forestry General Directorate in Turkey has been improved 187 MB Trac tractors, 68 farm tractors (adapted), 19 Koller K300 skyline, 15 URUS MIII skyline and 3 Gantner skyline machines as of 2004 as illustrated in Table 1.   Technical Features and Work Performance of Tractors: These tractors go into the yarder side with skidding roads and strips. In this areas tractors are used in two ways. The first way is; while tractors is staying on the road, to draw the product up to the road, which is found under the road or on the road, with the help of winch line. The second way is; to timber haulage the product directly on the surface, with skidding, while tractor is entering up to the yarder side. MB Trac 800-900-1000-1100 tractor types are being used especially at mountain areas in Turkey. These tractors are showed technical features Table 2.
In areas which has %30-55 gradient, MB Trac forest tractors can work comfortably. But farm tractors can work generally in areas which has a gradient until %30. Weight and dimension of the product that is skidded by forest tractors, is more than the weight and dimension of the product that is skidded by farm tractors. And also the movement capacity of forest tractors is higher than the movement capacity of farm tractors. Forest tractors   Table 3.

Technical Features and Work Performance of Skylines:
In Turkey, forest skylines are various types such as 1) Koller K300 skylines, 2) URUS MIII skylines, 3) Gantner skylines. Also, MB Trac 800-900-1000-1100 tractor types are being used especially at mountain areas. If the distance of maximum 300 m, Koller K300 skyline makes a transport. If the distance is max. 600 m, we use URUS MIII skyline and if the distance is between 1500 and 2000 m, Gantner skyline is used for transport. Koller K300 skyline and Gantner skyline which is assembles to trailer, transport from below to above also above to below. Skylines types are being used especially at mountain areas in Turkey. These skylines are showed technical features Table 4. Koller and URUS MIII skyline are mobile. Installation and uninstallation periods of these skylines are short. And also they are transported from a yarder side another very quickly. Assembly and dissembly periods of Gantner skylines are so long because of long institution and condition of lands. Koller and URUS skylines generally transport the product which is in the timber condition like this: One of the tip of product is transported surface and the other is in hook by these skylines. But Gantner skyline transports the timber completely in hook. In to posations, average times of timber haulage works and yields of machines are shown in Table 5.
As it is show in the Tablo 5, URUS MIII skyline's hour product was found as 7,9 and 12,9 m³ when the distance is 250 and 350 m. Koller K300 skyline's hour product was found as 2,8 and 10,0 m³ when the distance is between 150 and 225 m. Gantner skyline's hour product was found as between 2,2-6,4 m³ when the distance is between 300-800 m. Under these conditions, the fuel consumption of skylines change between 3 and 4 liters per hour. In skylines, average of 3-4 workers are worked according to land conditions of loading area, species of product which is timber haulaged and the intensity of work in the ramp. During the skidding of product with the help of tractors, treees and sapling which are found in the environment and also soil of forest can be damaged. Because of this, skidding strips and road must be opened in a place where the tractors are used. So, the roading in forest is increased but the drawing distance of tractors is decreased.

CONCLUSION
Skidding roads and strips must be done in a definite plan. These plans must be definetly suitable for an area and also practices must be put in order according to these plans. A wrong way, which is followed in the stage of timber hauling, causes spending more power and more money and also spending more time in timber hauling. It also causes less amount and quality of product. In addition, it will be damaged the soil of forest and youth. In respect of this study, the skylines' and tractors' unit volume transport expenses are more less than the other hauling methods (hauling with human and animal power). If we produce forest product cheaper and high quality, the profit of Forest Districts will be too much.