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Znanstveno-stručno i staleško glasilo
Hrvatskoga šumarskoga društva
Journal of Forestry Society of Croatia
      Prvi puta izašao 1877. godine i neprekidno izlazi do današnjeg dana
   ISSN No.: 0373-1332              UDC 630*
upute autorima


Krpan, A. P. B., Ivanović, Ž. UDK 630*377.2 001
Yarding Pedunculate Oak logs with the Steyr KSK 16 Cable Crane     pdf     HR     EN 75
Conclusions: This paper is a study on the possibilities of using the KSK
16 cable crane in hauling the pedunculate oak logs under the conditions of
highly moist lowland forest soils. Broad studies of work and time were done
within the field research, resulting in the survey of 339 circles by the stopwatch
study, according to the previously detailed time classification and whole-
day work surveys.

The average load was 2,55 m3 counting 2,18 pes of logs. The volume of the
mean log is 1,17 m3 length 4,9 m, peeled-log-diameter 55 cm. The biggest log
diameter was 90 cm, length 9,2 m, the biggest volume 4,2 m3.

Out of the 49,7% of the whole surveyed time, 15,7% was spent on full wagon
drive, 15,0% on loading, 12,1% on empty drive and6,9% on unloading. Of the
total surveyed time, 50,3% was spent on the general times. The major part of
the general time, 62,9% refers to technical breaks. Mealbreaks took 26,6%
from the general times, 7,5% from occasional jobs and 2,1 %from preparatory
finishing time. Additional time was 23,9% of the effective time.

During cable crane survey the average output was 67,42 m3/day. Effective
circle time is 9,03 minutes; total circle time together with the chosen additional
time: 11,19 min. Average time standard is 4,39 min/m3, and the average
expected daily output 102,5 m3.

The average speed of empty wagon drive is 2,68 m/s, full wagon 2,06 m/s.
The surveyed times of full and empty wagon drive were equalized with the
straight-line equation. They grow with the increase of the haul distance, the
more inclined growth being up to 300 m distance.
The average line pull speed with chokers is 0,57m/s, side haul 1,14 m/s, the
ratio being 1:2. The average line pull and haul distance is 17,5 m. Time input
for the two operations proportionally increases with the increased distance,
the haul speed behaving similarly. The line pull speed grows up to 25 m and
drops afterwards.
Time standard is equally proportional, and the daily output is a conversely
proportional value, to haul distance. Time standard for 75 m is 2,95 min/m3,
and 5,53 min/m3 for 575 m. The daily output for 75 m is 152,54 m3, 81,37 m3
for 575m. The output decrease factor shows that the 350 m-output is by 30%,
the one of 500 m by 40% lower when compared to the 100 m-output.
The working time of the cable crane takes 72,3% of the efficient time or
35,8% of the total surveyed time. By reducing the general times down to the
level of the additional times, the working time would amount to 58,3% in re-
alation to the total time.
Key words: cable crane; lowland; work and time study; time standard; producibility
Pičman, D., Tomaz, I. UDK 630*373.3 001
Determination of the Compartment Centre by the Application of a Personal Computer for the Purpose of Working out the Medium Distance for Dragging     pdf     HR     EN 91
Starčević, T. UDK 630*432.0+232
Selection of Damaged Trees and Remediation     PDF 105

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