In addition, a design method of weighting rod, whichcan ensure neutral point is in weighting rod, and reduce the rod parting nearby neu...

 
  • 同時(shí),初步解決了加重桿設計問(wèn)題,確保中和點(diǎn)在加重桿上,有效地減少中和點(diǎn)附近抽油桿斷裂問(wèn)題。
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