Nomenclature

value further inflates. Therefore, when RPM is around 240, the drilling system's optimum WOB is 8.8–11 kbl. At around 8843 ft, WOB is adjust to 8.8–11 kbl, the MSE value is minimized and close to the CCS of the formation. From 8843 to 9842 ft, WOB remains around 8.8–11 kbl, it drills with a relatively high efficiency and the average ROP is 19.4 ft/h. At 9731 ft, the flow rate increased to 1097.6 gal/min from 1056.0 gal/min and RPM increased to 258 from 249. The MSE value is minimized and MSE (min) = CCS while WOB reduced to 7.3–9.5 kbl. At 9888 ft, when WOB increases from 7.3 to 9.5 kbl, the MSE value rockets and MSE(min) > CCS. From 9843 to 10,499 m, WOB increases to more than 26.5 kbl, the MSE value is more than ten times of CCS and the average ROP is 11.2 ft/h. This indicates that when RPM is around 258, the drilling

Based on the above drilling parameters optimization analysis, it is also found that ROP is sensitive to high WOB values for rotating drilling with PDM, and increasing WOB does not always increase ROP but is more likely to decrease ROP. Moreover, the optimum WOB always changes with RPM for rotating drilling with PDM. The proposed method for optimizing drilling parameters can be used to real time estimate optimum WOB values with different RPM to drill a specific formation interval. It can be effectively and easily used, and is worthy to

In this chapter, MSE models respectively for directional or horizontal drilling and rotating drilling with PDM are established, meanwhile methods for drilling performance prediction and optimization based on MSE technologies are presented. The following remarks provide a

1. A formula between bottom hole WOBb and the surface measured WOB is developed, and the bottom hole WOBb has been introduced to calculate torque of bit of directional or

2. The MSE models respectively for directional or horizontal drilling and rotating drilling with PDM estimate MSE values with a reasonable approximation in the absence of reliable

3. ROP is sensitive to high WOB values for rotating drilling with PDM. The optimum WOB is low for rotating drilling with PDM compared with the conventional drilling without PDM, increasing WOB does not always increase ROP but is more likely to decrease ROP.

4. The method for optimizing drilling parameters can real time estimate optimum WOB values with different RPM to drill a specific formation interval with PDM. It could be effectively used to maximize ROP and allow operators to drill longer and avoid unneces-

5. Drilling performance prediction and optimization methods based on MSE technologies is worthy to be applied and promoted with highly diagnostic accuracy, effective optimizing

torque measurements, they can be widely used in the drilling industry.

system's optimum WOB is 7.3–9.5 kbl.

be applied and promoted.

156 Drilling

horizontal wells.

5. Summary and conclusions

summary with conclusions on the basis of case studies.

sary trips in rotating drilling with PDM.

and simple operation.



Acknowledgements

Author details

References

(Grant numbers: 51434009; 51521063; 51774301).

\*Address all correspondence to: chenxuyue2011@163.com

Xuyue Chen\*, Jin Yang and Deli Gao

DOI: 10.2118/183025-PA

Netherlands. DOI: 10.2118/92194-MS

Mechanics and Mining Sciences. 1965;2(1):57-73

China University of Petroleum, Beijing, China

This work was financially supported by Science Foundation of China University of Petroleum, Beijing (No.2462017YJRC050), National Key Research and Development Project (Grant numbers: 2017ZX05009-003; 2016YFC0303303), National Natural Science Foundation of China

Drilling Performance Optimization Based on Mechanical Specific Energy Technologies

http://dx.doi.org/10.5772/intechopen.75827

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