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1·They were using a mechanical shovel to clear up the streets.

他们用机械铲土机清理街道。

2·At the furnaces in the centre of the compound, sparks shower down as a mechanical shovel fills a red-hot crucible with coal and iron ore; molten steel pours from another.

在厂区中央的熔炉那里，随着机械铲把煤和铁矿石装满通红的坩埚当中，火星飞溅；铁水从另一个坩埚中注入。

3·Recommendations on how to perform the kinematic and dynamic research of mechanical shovels and the implementation of automatic control system for the operating process of the shovel are presented.

提出了如何开展挖掘机运动学与动力学的研究，以及采用挖掘机工作过程自动控制系统的建议。

4·Through analyzing on the changing course of 2100bl electric shovel central pintle, the improvement scheme of central pintle is proposed and demonstrated on the aspects of structure and mechanical.

通过对2100 BL电铲中央枢轴的更换过程的分析，提出了中央枢轴的改进方案，并在结构和力学的角度上进行了论证。