In the survey of the source of water supplying for town and major industry the group drilling pumping test is needed.

在城镇、工业大型供水水源地的勘察中，都要求进行群孔抽水试验。

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Designed with a form as from top to bottom and group drilling set, a new type of drilling machine for air hole for automatic molding line has been awarded a national patent.

新型钻气孔机用于全自动造型线，设计采用自上而下、群钻气孔方式。该设计已获得国家专利。

youdao

Designed with a form as from top to bottom and group drilling set, a new type of drilling machine for air hole for automatic molding line has been awarded a national patent.

新型钻气孔机用于全自动造型线，设计采用自上而下、群钻气孔方式。该设计已获得国家专利。

youdao