1·The calculations for the stroke, speed and acceleration of the plunger are summarized, providing a basis for selecting the structure and working parameters of the pump.
还综述了柱塞冲程、速度和加速度的计算，为特种抽油泵结构和工作参数的正确选择提供了依据。
2·A plunger is always longer than its stroke and only one end is available for pumping. Double-acting plunger pumps require at least two cylinders and plungers.
柱塞的长度总大于它的冲程，并只有柱塞的一个端面为液体增压。双作用柱塞泵至少需要两个缸体和柱塞。
3·When Wells run at one or some of the above states, and the practical down stroke axial load of the plunger is greater than the critical axial load, the wear of rod string and tubing will take place.
当抽油杆柱在上述一个或几个条件共同作用下达到偏磨临界条件时。杆管将产生偏磨。
4·The invention also provides a starting method of the variable stroke plunger pump.
本发明还提供一种变量柱塞泵启动方法。