基于缩尺模型的桥式抓斗卸船机应力应变特性研究

Study on stress and strain characteristic of overhead grab ship-unloader based on scale model

卸船机结构庞大,受力复杂,工作环境恶劣,现场试验难以组织。为降低试验成本,根据相似原理,运用量纲分析法研制了2 250 t/h桥式抓斗卸船机的相似模型,几何尺寸比例为1∶40。通过模型应变检测试验,得出俯仰梁与前拉杆上5个测点在满载荷的抓斗从起升位置运动至卸料位置过程中的应力应变呈现逐渐变小的规律,实验结果与有限元分析计算结果对比基本吻合。研究结果为卸船机安全性设计和维修策略研究提供理论依据和试验数据。

The ship unloader is the enormous structure,bearing complex loads and working in the severe environment,so it＇s difficult to arrange the site test. To reduce the test cost,a similar model is built for 2 250 t / h overhead grab ship-unloader with the dimensional method based on the similarity principle,with the physical dimension of 1： 40.Through model strain detecting test,the rule is obtained that the stress and strain of 5 measuring points on the pitching beam and front pull rod gradually decrease when the full-loaded grab moving from the lifting position to the discharging position. The test result is nearly identical to the calculation result by the finite element analysis. The study result can provide theoretic basis and test data for safety design of the ship unloader and research on maintenance policies.