Pcp Pump Desing

Abstracts courtesy of Ken Saveth, ksaveth@juno.com   "ANALYSIS AND OPTIMIZATION OF PROGRESSING CAVITY PUMP SYSTEMS BY TOTAL WELL MANAGEMENT" - Jim McCoy: Echometer Company   The need to increase oil production, reduce operating costs and increase net income from PC pumped wells, requires an integrated analysis of the pumping system including the performance and interaction of al the elements: thereservoir, the wellbore, the downhole pump, the rod string, the drive head, and the prime mover. Such system analysis can now be undertaken efficiently using portable laptop-based data acquisition systems in conjunction with the appropriate transducers and a suite o analysis software.     Field experience has resulted in the development of a procedure which insures that good results are obtainedwith the minimum of effort. It is the objective of this paper to outline this procedure or methodology with the hope that it will be of use to production personnel throughout the industry. The end result of such system analysis should be the complete visualization of the performance of a given pumping well at a given time and a set of recommendations to be followed if significant improvements canbe achieved.   In general, the following steps should be taken:   1. Establish the well's inflow performance to determine if additional production is   available   2. Determine the overall system efficiency as a means to identify wells which are inefficient.   & thus are candidates for mechanical/electrical changes to improve performance.   3. Analyze performance of downhole pump & downhole gasseparator.   4. Analyze mechanical loading of rods.   5. Analyze performance of prime mover.   6. Design possible modifications to improve existing system.   7. Implement cost effective changes & verify improvement.   METHODOLOGY   The steps to be followed in defining the performance of the system should result in the maximum of information with the minimum of time and effort. This is facilitated byhaving access to accurate and timely information about the well's characteristics, completion, well tests, etc. Although this may be initially time consuming, it is generally a task that has to be completed only once. Some sort of data base management system is helpful in maintaining this information current. The information should be organized by well into a summary Well Data File which can beaccessed by most of the application programs that are likely to be used. This eliminates having to re-enter the data.   BASIC SURVEY   Certain basic measurements are necessary to identify those wells that are the most likely candidates for improvement. experience has shown that this can be accomplished cost effectively by establishing the well's inflow performance (by measurement of the liquidlevel depth and casing pressure) and measuring the overall efficiency of the pumping system. This requires only the measurement of input power to the prime mover, determination of the producing BHP and accurate well test data. The producing BHP is obtained from liquid level and casing pressure measurements and then computed taking into account the affect of annular gaseous liquid column if present. Ifa digital acoustic fluid level survey is not available, the calculation of the PBHP from strip chart liquid level depth and casing pressure measurement can be performed on any PC using the program IPA or AWP which can be obtained free of charge from Echometer Company. Measurements of the fluid level and casing pressures also allow the determination of the net lift of the liquids.   The basicsurvey will indicate whether the efficiency of the pumping system is adequate and whether a low PBHP is present in the well. If either of these conditions is not satisfied, there is an indication that modification of the system or operating parameters could be beneficial and allow improved operation.   Without including the compilation of well data, and acquisition and processing of the acoustic,...