Journal of Korean Society of Forest Science (한국산림과학회지)

Korean Society of Forest Science (한국산림과학회)
권호 표지
DOI QR코드

DOI QR Code

Traction Performance Improvement Study on a Small-scale Tower Yarder Attached to a Farm Tractor

농업용 트랙터 기반 소형 타워야더의 견인 성능 개선에 관한 연구

  • Paik, Seung Ho (Forest Technology and Management Research Center, National Institute of Forest Science) ;
  • Choi, Yun-Sung (Forest Technology and Management Research Center, National Institute of Forest Science) ;
  • Cho, Min-Jae (Forest Technology and Management Research Center, National Institute of Forest Science) ;
  • Mun, Ho-Seong (Forest Technology and Management Research Center, National Institute of Forest Science) ;
  • Han, Sang-Kyun (Department of Forestry, Korea National College of Agriculture and Fisheries) ;
  • Kim, Dae-Hyun (Department of Biosystems Engineering, Kangwon National University) ;
  • Oh, Jae-Heun (Forest Technology and Management Research Center, National Institute of Forest Science)
  • 백승호 (국립산림과학원 산림기술경영연구소) ;
  • 최윤성 (국립산림과학원 산림기술경영연구소) ;
  • 조민재 (국립산림과학원 산림기술경영연구소) ;
  • 문호성 (국립산림과학원 산림기술경영연구소) ;
  • 한상균 (한국농수산대학 산림학과) ;
  • 김대현 (강원대학교 바이오시스템공학과) ;
  • 오재헌 (국립산림과학원 산림기술경영연구소)
  • Received : 2019.07.19
  • Accepted : 2019.10.28
  • Published : 2019.12.31
Download PDF
⟨ Previous Next ⟩

Abstract

In a cable yarding system, a small-scale tower yarder attached to a farm tractor wasdeveloped and used for small-diameter tree harvesting operations. Based on this design, improvement of traction performance was required for medium- and large-diameter tree harvesting operations. In this study, the mechanical transmission employed for the tower yarder was modified into ahydro-mechanical transmission system. Maximum traction forces, including tractor engine speed and hydraulic power pressure, were investigated, and comparisons were made between the mechanical and hydro-mechanical transmission systems. Six tractor engine speeds (1,200, 1,400, 1,600, 1,800, 2,000, and 2,200) and three levels of power transmission mechanism pressure (4.9, 6.9, and 8.8 MPa) were investigated in the two different transmission systems. Results showed a maximum traction force of 15,146.6 N at an engine rotation speed of 757 rpm in the current mechanical transmission system, and 36,140.0 N at anengine rotation speed of 1,575 rpm in the modified hydro-mechanical transmission system. The maximum traction forces for the hydro-mechanical transmission were 2.4 times greater than those of the mechanical transmission, and may therefore be applicable to medium and large-diameter tree harvesting operations. Thus,as a modified version of the conventional transmission system, the new hydro-mechanical transmission system may be cost-effective for use in large-scale cable yarding operations. In the future, however, it will be necessary to investigate problems that may arise from field application tests.

국내 임목수확작업에 사용되고 있는 트랙터 기반 소형 타워야더는 소경재 생산을 목적으로 개발되었으며, 중대경재 수확 체제로 변화함에 따라 견인 성능의 개선이 필요하다. 이 연구는 동력 전달방식을 기존의 기계식에서 기계 유압식으로 개선하여 타워야더의 최대 견인력을 비교·분석하였으며, 트랙터 엔진속도, 유압식 동력 전달 기구의 압력을 변수로 두고 견인 성능 실험을 실시하였다. 실험 수준은 트랙터 엔진속도(1,200, 1,400, 1,600, 1,800, 2,000, 2,200 rpm) 6수준, 동력 전달 기구의 압력(4.9, 6.9, 8.8 MPa) 3수준으로 선정하였다. 기존의 경우 최대 견인력은 엔진 회전속도 757 rpm에서 15,146.6 N의 최대견인력을 발휘하였으나 개선된 타워야더는 엔진 회전속도 1,575 rpm에서 36,140 N의 최대 견인력이 나타나, 최대 견인력이 2.4배 증가되었다. 이에 따라 중대경재 위주의 목재수확 현장에서 작업이 가능할 것으로 판단된다. 또한 기존 장비를 재활용하여 성능 개선함으로써 견인력이 큰 집재장비의 신규 도입 및 운영에 필요한 비용을 줄일 수 있을 것으로 기대된다.

Keywords

References

  1. Cho, M.J., Cho, K.H., Oh, J.H., Han, H.S. and Cha, D.S. 2014. Harvesting Productivity and Cost Using Tower-Yarders. Proceedings of the 2014 Spring Meeting of the Korean Forest Society 265.
  2. Han, W.S., Han, H.S., Kim, Y.S. and Shin, M.Y. 2008. The Yarding Productivity and Cost of Cable Yarding Operation by Yarder Attached on Tractor - Using the Chuncheon Tower-yarder. Journal of Korean Forest Society 97(6): 641-649.
  3. Korea Forest Service. 2018. Statistical yearbook of forestry. KOREA Forest Service.
  4. Nigerian Institution of Agricultural Engineers. 2007. Agricultural Tractor National Test Standard National Institute of Agricultural Engineering pp. 16.
  5. Oh, J.H., Hwang. J.S. and Cha. D.S. 2007. Development and Evaluation of Mathematical Model for Predictive Tension Force. Journal of the Korean Forestry Society 96(4): 448-454.
  6. Park, S.J., Kim, T.H., Kim, D.H., Kwon, K.Y., Kim, B.G., Oh, K.C., Park, K.J., Cho, Y.U., Lee, G.T., Yoon, Y.H. and Choi, B.C. 2007. Development of Tower-yarder with Tractor. Ministry of Agriculture and Forestry. Sejong, KOREA. pp. 2-3.
  7. Park, S.J. and Kim, B.K. 2008. Development of Tractor attached. Tower(1) - Design and Production-Journal of the Korean Forestry Society 97(1): 61-70.
  8. Ryu, K.H. 2004. Tractor Engineering Principles. Munundang. Seoul.
  9. Song, T.Y., Kim, J.W., Cho, K.H. and Oh, J.H. 2009. Forest Harvesting System, National Institute of Forest Science. Seoul, KOREA. pp. 1-2.