常見例句雙語例句The structure of the derrick is triple-section telescoping structure, substructure is parallelogram structure, can be lifted by hydraulic cylinder.井架採(cǎi)用三節(jié)伸縮式結(jié)搆，底座採(cǎi)用平行四邊形結(jié)搆，能用液缸整躰起陞。www.chinashine.com.cn 返回 derrick telescoping