“Sucker rod pumping is the most highly used form of artificial lift in the world. And these days, most new wells are either highly directional or horizontal. The software used by the industry to design sucker rod strings is based on data collected in vertical wells. Therefore, it isn’t sufficiently accurate for design and analysis of rod strings in our newer wells.

ALRDC is excited to help sponsor an industry-wide R&D project to collect downhole dynamometer data on deviated and horizontal wells. This project provides the opportunity for many companies to share in the gathering and use of this new understanding. It can be used to enhance the design and analysis tools we use. This will provide significant technical and economic advantages to all who market, design, install, and use sucker rod pumping in deviated wells.

All companies that provide or use sucker rod pumping are encouraged to join this effort. ”

Cleon Dunham
President of Artificial Lift R&D Council
President of Oilfield Automation Consulting

“Many of the several thousand of wells that have been completed as deviated or horizontal wells are currently using or in the near future will be using rod pumps to produce economically. Rod string design and pump operation analysis from dynamometer measurements are now undertaken by computer models originally developed for vertical wells and validated by the industry sponsored SANDIA Downhole Dynamometer project. No such validation has been performed on the rod string computer models that have been extended to deviated wellbores, those models are based purely on theoretical assumptions.

It is unwise and economically risky to apply the results of such extended models without having adequate validation of their accuracy.

Directly measured load data is required to perform such validation or to improve the accuracy of the existing software. The principal objective of the proposed project is to provide the necessary data about actual loading experienced by the rod string in a variety of non-vertical wellbore geometries. This task requires the development of a new generation of down-hole sensors and performing field measurements through the collaboration of operators and service companies under the guidance of ALRDC and its members. The success of this project rests in the willingness of all companies that use or provide sucker rod pumping systems to participate in this effort.”

A.L. Podio, Ph. D.
Co-Author of “The Beam Lift Handbook”

“While the Sucker Rod Lift (SRL) method continues to be the most used technique for producing all types of oil, gas, vertical, deviated and horizontal wells, the main computer program software design tool has been recently evaluated showing variations in anticipated downhole loads at various depths in the field tested wells. This evaluation showed that there still are misconceptions and assumptions such as compressive loads and buckling that provide a wide variation compared to the Sandia test data obtained a few years ago.

Over time the computer design programs have been improved and have been modified to try to provide a more accurate prediction of rod string loads. However, downhole deviation surveys and resulting side loads were not originally collected during the Sandia study, which may have contributed to the differences in the expected loads.

Based upon these results a new project has been developed under the coordination of the Artificial Lift Research and Development Consortium (ALRDC) to attempt the development of a current generation downhole data collection tool and well evaluation testing to provide the industry with a more accurate data base to be used to develop better design software programs. This industry study should provide the much needed details on downhole deviation effects in vertical, horizontal, S-type and highly deviated SRL wells. Ultimately, these results should be able to answer the questions on the rod string loads with well depth and whether or not there is compression and/or buckling of the rod string with depth.”

Norm W. Hein, Jr.
President & Managing Director of Oil & Gas Optimization Specialists, Ltd.

“I wholeheartedly support the Horizontal Well Downhole Dynamometer Data Acquisition Project (HWDDDA). This is a logical and much needed extension of the 1990s work which pertained to vertical wells. My company, Nabla, participated in the earlier project. Our role was to make surface dynamometer measurements at the exact same time as the downhole dynamometer tool was making its measurements. The surface data was used in various downhole card programs for comparison with actual cards being measured with the downhole dynamometer (Albert) tool. In this way the downhole card programs could be evaluated and improved.

Our industry now finds itself in the era of horizontal wells and massive frac jobs. Horizontal wells are deviated before they reach the horizontal. Our industry needs downhole measurements in deviated wells that serve the same purposes that the 1990s measurements served for vertical or near vertical wells.

The work proposed for HWDDDA strikes close to my heart. The current methods for deviated wells trace to my 1992 SPE paper “Design and Diagnosis of Deviated Rod-Pumped Wells”. The downhole friction law in that work was largely theoretical. The practical import of the Gibbs Conjecture is that the precision of pump cards can be improved by improving the friction law in the wave equation. This is exactly what can happen when downhole measurements from the HWDDDA project become available. The theoretical law now used can be evaluated or replaced by a better law.”

Dr. Sam G. Gibbs
Petroleum Hall of Fame Inductee
Author of “Rod Pumping: Modern Methods of Design, Diagnosis, and Surveillance”