Rod Pumping Selection Design

The selection and design of the artificial lift equipment will continue to be a significant event in the life of most oil wells. The resulting profitability will either be increased or diminished by the artificial lift equipment choices, and the credibility of the designer will be enhanced or lowered. The designer should be aware that the system efficiency is becoming increasingly more important, since energy costs continue to rise. The best artificial lift selection and design will make the greatest amount of money (highest present value cash flow) over the life of the project. [2] In the planning stage the following three factors must be evaluated: (1). the oil and gas production and revenue over well life, (2). the operating cost over well life, and (3). the capital cost of the equipment. Of these --the most significant is the revenue. To maximize revenue, the oil reserves should be produced in a timely fashion. Thus a design is required that will produce the well near its capacity or at a high rate throughout its life. The operating cost over life normally far exceeds the capital cost; thus, particular attention should be given to reducing recurring monthly costs (i.e. energy, maintenance, and repairs). Often the more efficient and trouble free equipment is initially more expensive. Good records must be kept and evaluated to determine the operating cost advantage of the installed equipment. Digging out the monthly costs may be a tedious process even in these days of data bases and computer manipulations. The capital cost is easy to obtain. The vendors and service companies will help in this endeavor. Bids are often obtained and, unfortunately, sometimes not carefully reviewed. The bid specifications should be carefully written and the received bid then thoroughly analyzed. Do not waste money by purchasing excessively large equipment or buying features that are not needed. Be sure all equipment will meet the objectives of being efficient and trouble free. Do not overlook the service required and its availability and quality in the planned location. This paper will discuss the more important considerations in rod pumping selection and design.