The Journal of Korea Institute of Information, Electronics, and Communication Technology (한국정보전자통신기술학회논문지)

Korea Information Electronic Communication Technology (한국정보전자통신기술학회)
권호 표지
DOI QR코드

DOI QR Code

Analysis of Equivalent Torque of 78 kW Agricultural Tractor during Rotary Tillage

78 kW급 농업용 트랙터의 로타리 경운 작업에 따른 등가 토크 분석

  • Received : 2019.07.26
  • Accepted : 2019.08.05
  • Published : 2019.08.30
Download PDF
⟨ Previous Next ⟩

Abstract

This paper is a basic study for the performance evaluation, durability improvement and optimal design of tractor transmission. The engine torque of the 78 kW agricultural tractor during rotary tillage was measured using CAN communication. It was calculated with equivalent torque and then analyzed. In order to develop a reliable tractor, it is important to convert measured torque in various agricultural operations into equivalent torque and analyze it. The equivalent torque was calculated using Palmgren-Miner's rule, which is a representative cumulative damage law. The equivalent torque of rotary tillage period and steering period are 229.2 and 136.7 Nm, respectively. The maximum and average torque during rotary tillage period are 336.0 and 234.4 Nm, respectively. The maximum and average torque of the steering period are 288.0 and 134.6 Nm, respectively. The engine torque in rotary tillage period is higher than in the steering period because of cultivation of soil through PTO. The maximum and rated torque of engine are 387.0 and 323.0 Nm, respectively, which are 183% and 136% higher than the equivalent torque during rotary tillage and of steering section. Because transmission of agricultural tractor in Korea companies is generally designed by the rated torque of engine, there is a difference from measured torque during agricultural operations. Therefore, it is necessary to consider it for optimal design.

본 연구는 트랙터 변속기의 성능평가, 내구성 향상 및 최적 설계 등을 위한 기초 연구로써 로타리 작업에 따른 78 kW급 농업용 트랙터의 엔진 토크를 CAN 통신을 이용하여 수집하고, 등가 토크를 분석하였다. 신뢰성 높은 트랙터 개발을 위해서는 실제 농작업 환경에서 발생하는 부하를 등가 토크로 변환하여, 분석하는 것이 필요하다. 등가 토크는 대표적인 누적 손상법인 Palmgren-Miner 식으로 작업 및 선회구간에 대하여 계산되었으며, 각각 229.2, 136.7 Nm로 나타났다. 로타리 작업구간에서 최대 및 평균 토크는 각각 336.0, 234.4 Nm로 나타났으며, 선회구간의 최대 및 평균 토크는 288.0, 134.6 Nm로 나타났다. 로타리 작업구간에서의 엔진 토크는 PTO를 통해 토양을 경운하기 때문에 선회구간보다 높게 나타났다. 엔진의 최대 및 정격 토크는 각각 387.0, 323.0 Nm로, 로타리 작업 및 선회구간의 등가 토크보다 각각 183%, 136% 높게 나타났다. 국내 트랙터 회사는 일반적으로 엔진의 정격 토크를 기준으로 변속기를 설계하기 때문에, 실제 작업 토크와 다소 차이가 있다. 그러므로 최적 설계를 위해 실제 작업 토크를 고려하는 것이 필요할 것으로 판단된다.

Keywords

References

  1. D. C. Kim, Y. S. Kang, "Case study of accelerated life test method for agricultural tractor transmission", Journal of biosystems engineering, Vol. 34, No. 5, pp. 325-330, 2009. https://doi.org/10.5307/JBE.2009.34.5.325
  2. K. J. Sim, W. Y. Cho, Y. J. Lee, "Development on Test Specification of Reliability of Agricultural Tractor", The Korean Society of automotive engineers, Vol. 2011, No. 9, pp. 43-48, 2011.
  3. K. H. Han, K. U. Kim, Y. G. Wu, "Severeness of transmission loads of agricultural tractor for rotary operations in poorly drained paddy field", Journal of biosystems engineering, Vol. 24, No. 4, pp. 293-300, 1999.
  4. J. H. Jang, "Durability analysis of compound planetary gear of hydro mechanical transmission", Master dissertation, Chungnam National Univ., Daejeon, Korea. 2018.
  5. Y. J Park, G. H. Lee, S. C. Kim, "Accelerated Life Test Method for Agricultural Tractor Transmission Part I : Equivalent Load Method", The Korean society of the agricultural machinery, Vol. 20, No. 2, pp. 86-87, 2015.
  6. D. Y. Kim, I. B. Lee, L. J. Liang, S. K. Lyu, "A Study on Components Load of 5MW Wind Turbine Pitch Drive" Journal of the Korean Society of Manufacturing Process Engineers. Vol. 13, No. 1, p.p 115-120. 2014. https://doi.org/10.14775/ksmpe.2014.13.1.115
  7. W. Jung, A. Ismail, "Method of Determining Acceleration Factors for Agricultural Tractors" International Conference on Quality, Reliability, Maintenance and safety engineering. 2011.
  8. K. Thomsen, P. Sorensen, "Fatigue loads for wind turbines operating in wakes", Journal of Wind Engineering and Industrial Aerodynamics Vol. 80, No. 1999, p.p :121-136. 1999. https://doi.org/10.1016/S0167-6105(98)00194-9
  9. MAFRA, "Development of Optimal Tillage System Based on Soil Physical Properties", Ministry of Agriculture, Food and Rural Affairs, Sejong, Korea, 2007.
  10. J. H. Kim, K. U. Kim, C. W. Choi, Y. G. Wu, "Severeness of Transmission Loads of Agricultural Tractors", The Korean society of the agricultural machinery, Vol. 23, No. 5, pp. 417-426, 1998.
  11. S. H. Baek, K. Y. Lee, S. J. Mun, S. S. Cho, W. S. Joo, "Fatigue Cumulative Damage and Life Prediction of Uncovered Freight Car Under Service Load using Rainflow Counting Method", Transactions of KSAE, Vol. 13, No. 2, pp. 1-9, 2005.
  12. S. C. Ashmore, A. G. Piersol, J. J. Witte, "Accelerated service life testing of automotive vehicles on a test course", Vehicle System Dynamics. Vol. 21, pp. 89-108. 1992. https://doi.org/10.1080/00423119208969004
  13. Standard ISO 6336-1, "Calculation of load capacity of spur and helical gears" Geneva, Switzerland. 2007.