短语词组短语bit -rock mutual action 钻头与岩石互作用bit and rock 钻头与岩石rock bit 岩石锧头;岩石钻头;凿岩钻头rock bit sharpening machines [机]矿井钻头刃磨床rock bit design 钻头研制rock bit cone 钻头牙轮tricone rock bit 三牙轮钻头;三维式岩石钻头;三牙轮岩石钻头 返回 bit rock