【摘要】 <正> 一、前言 集材——50拖拉机是当前我国森林伐区集运作业的重要机械设备。集材——50拖拉机是在极其艰难而恶劣的作业条件和环境中进行多种工况作业的。严冬(-45℃)与酷暑(+35℃)温差可达80℃左右;湿度大;负载运行于沟、塘、倒木、树根俱在的山林中;原条阻力的随机性等等。多种工况主要有竖巴掌、背运、转弯、过倒木、堆木头等。这些是目前造成集材——50拖拉机零、部件断裂失效情况严重的原因之一。 目前,我国集材——50拖拉机存车量为××××台,由于其断裂失效一般一年要大修或中修一次,一台一次大修费为8000—10000元。这样,对集材——50拖拉机进行断裂分析与技术改造,是势在必行且具有很大经济意义的事了。更多还原

【Abstract】 Ji-Cai-50 tractor is the specially used machine of wood-skid for forestry in north-eastern forestry area of China. In the process of working, often occurs the fracture of some major parts.This paper shows not only the occurrence of fracture of longitudinal beam, rear axle hausing and track roller, but also the present condition of fracture failure.In this paper, from the factor of being loaded with force, technique and temperature etc, the reasons of fracture are primarily analysed. The necessity of transformation and the problem of economic beneficial result are also suggested.更多还原