Pattern Recognition Applied to Dynamometer Cards For Sucker Rod Pumping Diagnosis

This paper discusses a numerical pattern recognition scheme NUPRO*. NUPRO is used to diagnose rod or subsurface pump problems by recognizing downhole dynamometer cards. NUPRO discretizes a dynamometer card into a set of points. Three point picking methods have been developed for NUPRO: constant position increment, constant time increment, and constant arc length increment. These methods vary the accuracy and run time of NUPRO. These methods were tested with a library of 37 known cards (cards l-37) and 100 unknown cards (cards 38-137).