抽油机设计模型示功图的研究

Model dynamometer card for pumping unit design

模型示欢图是指在抽油机正常工作条件下，能包容该机型各种工况，使抽油机的各项动力性能指标受到最恶劣工况考验的示功图。以现场实测示功图为基础，运用多元统计分析理论，结合理论研究成果和现场经验，给出了一种能预测在正常稀油抽汲工况下油井地面示功图参数的方法。为在抽油机设计中充分利用各构件和减速器的额定承载能力，提出在最大下泵深度只受抽油机结构承载能力的制约、减速器额定输出轴净扭矩利用率最趋近于１且小于１．１的工况来确定模型示功图。

The model dynamometer card is a dynamometer card that involves all kinds of working conditions of a given type of pumping unit, including the most severe condition for making trial of the various dynamic characteristic indexes of the unit.On the basis of the surface dynamometer cards measured on site, and by use of the multielement statistic theory, a method for predicting the parameters on the surface dynamometer card of a unit for pumping normal thin oil is presented. To make full use of the rated load capacity of all the components of the unit and the gear reducer, it is put forward that, in case that the setting depth of the subsurface pump is restricted only by the load capacity of the pumping unit structure, the model dynamometer card should be determined with a utilization ratio of the rated output net torque of the gear reducer close to 1and less than 1.1.