| Autor: |
Sanjit Roy, Andrew Dzialowski, M. S. Albrecht, F. K. Mody, A.H. Hale |
| Rok vydání: |
1995 |
| Předmět: |
|
| Zdroj: |
All Days. |
| DOI: |
10.2118/29424-ms |
| Popis: |
* Earlier experimentation demonstrated that the friction coefficient and wear of shale were highly dependent upon the chemistry of the drilling fluid. Since 70% of the formations drilled are shale, it was important to determine what additives might reduce wear of shale by a tool joint and/or lower the friction coefficient between a drillstring and shale. An examination has been undertaken to determine the effectiveness of various additives to alter the coefficient of friction and reduce wear on shale. This is an exceptionally important question when considering that most of the footage drilled is that of shale. Lower friction coefficients while drilling shale should improve the capability for longer-reach wells and reduced trouble costs. Reduced wear lowers the potential for key seating and thus limits costs. Because there is no relationship between wear and the coefficient of friction, it is important to identify reagents that can both lower the friction coefficient and reduce wear. The results indicate unique classes of chemicals are capable of lowering the friction coefficient and reducing wear. These chemicals can be incorporated into functional drilling fluids which are environmentally acceptable depending upon the concentration. In addition results are shown which demonstrate the unique capabilities of applying an electric potential across a shale matrix. Experiments are described that demonstrate that the presence of an electric potential lowers the friction coefficient and reduces the wear in a variety of drilling fluids both water-based and oil-based. This reduction is sufficient to lower the friction coefficient on shale in a water-based mud to a friction coefficient similar to that of an oil-based mud. |
| Databáze: |
OpenAIRE |
| Externí odkaz: |
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