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作者用普通砂型冒口与空心微珠保温冒口工艺对比的形式,说明采用空心做珠保温冒口套后,能获得明显的技术经济效益。
The author uses the comparison between ordinary sand-type riser and hollow-bead thermal insulation riser technology, which shows that the technology of hollow riser riser can obtain obvious technical and economic benefits.