top slice meaning in Chinese

堰板上唇，上堰板

Gas control of top slice working face with stage roadway
腰巷治理顶分层工作面瓦斯
Application of gas drainage from gob in gas control of top slice
采空区抽放在顶分层瓦斯治理中的应用
Inquiring into gas emission law from top slice during slice mining of an extra - thick coal seam
特厚煤层分层开采顶分层瓦斯涌出规律探讨
Analysis on danger of pressure bump when fully mechanized sublevel caving mining face passed through terminal mining line of top slicing seam
综放面过上分层终采线冲击地压危险性分析