Large Track-type Tractors Rollover And Falling Object Protective Structure Design Calculations

Roll-over protective structure (ROPS) is a device which installs on out of construction vehicle . When the vehicle rolls over , ROPS can reduce the possibility of being injured for the operator who wears a safety belt. Falling-object protective structure(FOPS) can block objects (such as trees , rocks) so that it supplies protection for the operator . ROPS and FOPS are designed and made of whole steel structure, which is called roll-over and falling-object protective structure and inevitable outcome for people to protect themselves instinctly.This paper takes the large type of track bulldozer TY320 as an example to study roll-over and falling-object protective structure based on the definition and function of the structure , and the laboratory static states, experimental standard, the rule of deflection-limiting volume from the international standards(ISO 3471:1994, ISO 3449:1992 and ISO 3164:1995).According to the demands of the design standard, the paper analyzes the deflecting process of ROPS/FOPS, the mechanics analysis(including calculation, extreme limit to carry the lotus settle, non-symmetry flection strength calculation) towards ROPS/FOPS, through a finite analysis counting software ANSYS and optimized design by building up mathematics model as well, then designs the structure by means of three dimensional CAD software Pro/Engineer .A set of integrity theories of design calculation method is given in the end of the paper.The results of the paper can not only carry on the pit in the strength verifing towards roll-over and falling-object protective structure of the engineering vehicle that already have had, but also be used in the new product development design of roll-over and falling-object protective structure. The new solution puts forward a new idea and basis for the studyand development of roll-over and falling-object protective structure in the future.