Analysis And Structure Of The Excavator Cab Safety Performance Improvement

Falling Object Protective structure & Roll-over protective structure (FOPS&ROPS) are a steel structural system installed on grab machine, its primary function is to avoid operators being crushed in the event of the vehicles encountered falling-object or roll-over. Construction machine manufacture has a great development in domestic, some of construction machines which are exported to international market must be equipped with the FOPS&ROPS. On this background, this paper studies the performance of FOPS&ROPS which is made by Hunan Sunward Machinery Co. Ltd.On the basis of referring many relevant works and criterions extensively, the study status and introduce the current standards on the performance requirements and test methods of the FOPS&ROPS have been summarized in the paper firstly. Then we discusses that ROPS numerical simulation is a material -nonlinear and geometry-nonlinear process, by this, nonlinear finite element method has been used on computer analyzing simulation of ROPS. Considering the precision and time consume of calculate, some structures have been ignored, appropriate material model has been chosen. At the first time we found a nonlinear finite element model of the ROPS by all using beam finite element, by much of calculation, get the displacement—load curve and energy—absorbability capability of model, analysis showed that there are three process during the deformation, they are elastic-deformation, elastic and plastic-deformation, plastic structure-deformation. The paper also found a model by using shell finite element, stress and strain, plastic joint position of the model has been got by analyzing shell model. Then, according to the national standards and experimental project, experiment researches have been done to the SWE38 excavator cab. And the experiment has got a obvious and more precision result by firstly using the virtual instrument to show the every performance index of ROPS in the experiments. Contrasts between emulation results and experimental results have been done to analyze the reason of inaccuracy. The contrast results indicated that the precision of finite element mode is available. Though the above work, computerized emulation method for analyzing performance of ROPS is established.Finally, count on the bad energy-absorbability and dehisce of soldering joints, several shape of plastic joint holes have been given, by this, a controllable plastic area has been shaped which can improve energy-absorbability of cab and protect welding joints. According to this project, a beam-shell combined model has been established and optimized. Compared with the initial simulation result, a better effect has realized by using the controllable plastic area method.