This paper details a program that has improved the quality, quantity, and usage of dynamometer surveys in the Duri Field. The programs' evolution, from an evaluation of various dynamometer data gathering systems, to a comprehensive well surveying and lift system optimization program, is detailed. This comprehensive program, is detailed. This comprehensive system includes routine well monitoring, problem evaluation, minicomputer problem evaluation, minicomputer database, and personnel training. This program has resulted in significant program has resulted in significant improvements in individual well profitability, optimum utilization of well profitability, optimum utilization of well servicing equipment, and superior engineering design data.
The Duri Field utilizes only beam type pumping units and sucker rod pumps for pumping units and sucker rod pumps for lifting produced fluids. This system is used because it is capable of reliably handling the combination of high fluid temperatures and significant sand production, which are common to steam flood production, which are common to steam flood operations. As is true of all lift methods, monitoring the performance of the lift system is important in order to maximize production. Industry experience has shown dynamometer surveys to be the most effective monitoring tool for shallow steam flood rod pumping wells. Dynamometers surveys, or "dynos", are used to accurately diagnose the condition of the downhole pump and rod string. This is accomplished by recording the surface loads carried by the sucker rod and its position in the stroke cycle of the pumping unit. Figure l illustrates a typical X-Y plot of this load versus position data, which is referred to as a position data, which is referred to as a "dyno card".
One of the most common uses of a dynamometer survey is to determine if a well is "pumped off". Here "pumped off" means that the operating fluid level is drawn down to the pump intake depth, which is usually near the bottom of the well. This pumped off condition is determined from the shape of the dyno card. A dynamometer survey can also be used to determine the condition of the rod pump. Load checks of the traveling and standing valves reveal whether or not a pump is worn. These two items; a load vs. position plot, and valve checks, are the key position plot, and valve checks, are the key components of a "simple dyno", and their analysis has been discussed extensively in technical literature. Table 1 is a complete list of the data reported in "simple dyno" tests taken in the Duri Field. These "simple dyno" tests, which reveal pump condition and operating fluid level, allow determination of whether a production drop is due to a worn pump, production drop is due to a worn pump, or to a reduction of fluid inflow to the wellbore. They also show evidence of other problems, such as gas or steam locking, problems, such as gas or steam locking, rod parts and tubing leaks.
Determination of whether pumps are worn and simply need changing, or whether other more extensive remedial or stimulation measures are necessary, was the initial goal of the Duri dynamometer program. program. P. 155