Each of the four legs contains a simple screw jack with a thrust bearing that is operated telescopically inside of two tubes.

 
  • 四條腿中每個(gè)都裝有一個(gè)簡(jiǎn)單的螺旋千斤頂,千斤頂中又有一個(gè)在兩根管道中做伸縮操作的推力軸承。
今日熱詞
目錄 附錄 查詞歷史
国内精品美女A∨在线播放xuan