Stability Analysis of Counterbalanced Forklift Trucks

카운터밸런스형 지게차에서의 안정도 해석

  • Kim, Jae Beom (Department of Safety Engineering, Chungbuk National University) ;
  • Shin, Woonchul (Department of Safety Research, Occupational Safety and Health Research Institute, KOSHA) ;
  • Park, Jai Hak (Department of Safety Engineering, Chungbuk National University)
  • 김재범 (충북대학교 안전공학과) ;
  • 신운철 (한국산업안전보건공단 산업안전보건연구원) ;
  • 박재학 (충북대학교 안전공학과)
  • Received : 2015.02.02
  • Accepted : 2015.04.10
  • Published : 2015.04.30


Forklift truck is a very convenient transportation vehicle and widely used in industries. However, a lot of overturn accidents occur during operation because of poor understanding on the stability of forklift trucks. The stability of a forklift is defined by the minimum slope of the ramp where a forklift truck overturns. According to the KS BISO 22915-2 code, the stability is determined from the four kinds of stability tests. The equations for the stability of a forklift truck were proposed already in several published literatures and the equations can be used conveniently to estimate the stability and examine the effects of design parameters in forklift trucks. However, because the detail derivation procedure was omitted, it is very difficult to examine the accuracy of the proposed equations and to modify the equations for other types of forklift trucks. In this paper the stability equations were derived again with detail derivations for the four kinds of stability tests. And the effects of acceleration or centrifugal forces were also additionally included in the equations and minor corrections were also made.


forklift truck;stability analysis;stability triangle;overturn


Supported by : 충북대학교


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