The authors think that the planetary gear pumping unit can work with long stroke or ultra-long stroke as the blue ele phant, it is characterized by impact structur...

• 认为行星齿轮抽油机与无游梁抽油机一样，可以实现长冲程或超长冲程，具有结构紧凑、体积小、重量轻和移运方便的特点，它克服了无游梁抽油机在换向方面存在的弊端，具有换向可靠性高和使用寿命长等优点。