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1978年,世界矿业出现了一个停滞不前的状况,面对这种不景气的趋势,采矿设备的制造厂商则侧重于改进现有的设备和生产一些新的中小型设备以填补其原系列产品中的空缺。在露天矿采掘设备方面,美国B-E公司宣称有一种新的50R型牙轮钻机。该机可钻直
In 1978, the world mining industry was in a state of stagnation. In the face of this downturn, manufacturers of mining equipment focused on improving existing equipment and producing some new small and medium sized equipment to fill the original series In the vacancy. In the open pit mining equipment, the United States B-E company claims that there is a new type 50R cone drill. The machine can drill straight