A system has been developed based on a powerful portable microcomputer and an integrated data acquisition package which allows real-time visualization of pumping well performance.
The system combines all the necessary elements to obtain a complete analysis of the performance of the pumping system which includes the pumping unit, the wellbore, and the reservoir.
The data acquisition package is connected to the expansion slot of the computer and consists of the necessary analog and digital channels to process data from standard transducers such as acoustic, pressure, temperature, rod load, displacement, etc.. Detailed surface unit performance curves such as dynamometer, speed, acceleration, power etc. can be obtained and analyzed. When the instrument is used in conjunction with an acoustic pulse generator and receiver, it digitizes and stores the reflected acoustic signals which are digitally filtered and automatically processed to determine the liquid level. This is undertaken under program control so that a continuous recording of fluid level vs. time is obtained along with the pumping unit performance parameters.
Fluid level data is processed by the software to calculate bottom-hole pressure as well as flow into and out of the well bore. Changing the well from flowing to shut in conditions allows recording of pressure buildup data which is then interpreted in terms of reservoir parameters.
The Well Visualization display can be used as a diagnostic cool to optimize pumping well performance on a periodic basis. The present performance of the well is compared to its recorded past performance and in the case where significant differences are noted, a more detailed analysis is undertaken to recommend changes in operation or remedial actions. In critical well applications, the system can function as a stand-alone dedicated controller.
Figure I is a schematic diagram of the Well Visualization System which results from the integration of various surface measurements with well data base information and with software packages designed for diagnostic analysis of well performance. The system's objective is to yield an accurate and timely analysis of the well for the present operating conditions and to predict the effect of operational changes on well performance.
Integration of these elements has been made possible only recently through the development of portable microcomputers and hybrid data acquisition electronics, improved low cost transducers, and PC based analysis, data base management and graphics software.
Well performance in the context of this paper addresses the complete well system including: the reservoir, the wellbore and the pumping components. Visualization of well performance is thus defined as: the ability to understand how these elements interact to yield the present conditions of pressure, flow rates, loads, efficiency, etc..
This ability allows the production engineer to evaluate the effect of changes in the operating parameters such as speed, stroke, surface pressure, on/off time, etc. and/or changes in the well configuration such as pump depth, rod sizes, surface unit geometry, well stimulation, etc. on the overall performance of the well.
For many years, the industry has had access to the individual components of this system: acoustic well soundings, dynamometer measurements, well test records, pressure sensors, transient well test data, etc..