In order to analysis of the yarding operation system with a Swing-yarder, yarding operation time, yarding operation efficiency and yarding operation system were investigated.
The ratio of unhook, choking and yarding time in the main operation time was the highest. Also, the ratio of setting-up and dismantling time in accessory operation time was the highest. Therefore, it is necessary to educate and train the choking man and operator in order to raise the ability and the efficiency of lateral yarding operation and to reduce the setting-up and dismantling time.
In this investigation location, an average yarding timber volume of the uphill yarding and downhill yarding was 6.12㎥ and 7.32㎥ per a day and man, respectively. The efficiency of yarding operation by a Swing-yarder was higher than the result of another existing study by manpower and plastic log chut, etc. Yarding productivity with a Swing-yarder was very efficiency.
The relationship of the distance and time of lateral wire traction and the distance and time of lateral yarding was showed low significance. It is necessary to raise an operation ability through the education and training of choking man and operator. Also, the relationship of the distance and time of yarding operation was showed high significance and slower than Tower-yarder operation. Therefore, it is necessary to raise the ability of Swing-yarder and to educate and train the operator.