PUMP CARD ANALYSIS SIMPLIFIED
A dynamometer pump card is a plot of the calculated pump loads and pump plunger positions during one complete stroke of the pumping unit. The plot is used to analyze pump performance. The pump card is normally calculated from measured surface polished rod load and position data. Different methods are used to display and plot so-called "Pump Cards". Sometimes the so-called pump card is actually a plot of sucker rod load and position, or maybe a sinker bar located above the pump. Several advantages exist for plotting the pump card as the load that the pump plunger applies to the sucker rod. First and foremost, the pump plunger card is easier to interpret and shows more mechanical and reservoir information. Visual estimates (high, medium and low) of the pump intake pressure are obvious from the pump card. Also, the zero load line on the pump plunger card indicates the quality and accuracy of the surface load and position measurements and computations. Examples are shown of the pump plunger card, interpretation of the pump plunger card and also plots of loads in nearby sucker rods and sinker bars that are sometime called pump cards. This paper recommends having the "Pump Card" represent the loads that the pump plunger applies to the sucker rod string and not represent loads in some nearby rod in the sucker rod string.