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1981年12月在上海召开了《φ250/φ310型矿用扩孔器研究》技术鉴定会。与会代表认为,φ250/φ310型矿用扩孔器在应用露天矿山钻孔在国内是首创,是一项填补
December 1981 held in Shanghai, “φ250 / φ310 Mining Reaming Research” technical appraisal. Participants that φ250 / φ310 type of mining reamer in the application of open-pit mines in the country is the first to be a fill