Assessment of tractor B11 (B14) cab safety

Abstract

In case of tractor overturning the issue of driver’s safety plays an important role. The risk of damage is possible to be reduced if a special protective device - Roll-over protective structure (ROPS), - is used. Currently, ROPS is a prerequisite for any tractor equipment and like all safety devices is to be subject to mandatory certification. According to GOST, ROPS assessment tests present a sequence of static (side, vertical, and longitudinal) structural loadings completely imitating the overturning machine. The loading values are determined (coordinated to) by the mass of the entire tractor. The compliance criterion is the absence of the structural failure and the inviolability of the intended limited location of the operator (Deflection-limiting volume - DLV), provided that the required impact energy is absorbed when certain load levels are reached. The article presents a method of certification testing of the ROPS protective structure on the example of tractor B11 (B14) cab. To calculate the absorbed impact energy, an experimental dependence of the lateral force on the application of force displacement point was constructed. Energy was considered as the area located under the curve of this dependence. As a result, all the experimental values of force and energy exceeded the values required by GOST. The ROPS under study has passed the entire loading cycle without destruction and penetration of the structural elements into a limited DLV area. As a result, a conclusion on the safety of the ROPS for machines weighing up to 25 t was drawn and a certificate of conformity was issued.