Unformatted text preview: shows a good power-function correlation between DSE and ROP when the data is grouped according to
the WOB. Three different regions are identified on the correlation: (1) Inefficient drilling with high DSE and low ROP; (2)
Efficient drilling with low DSE and high ROP; (3) Transition region located in between of region 1 and 2.
Bit HSI is the main driver to move from the inefficient to the efficient drilling region at constant WOB. The limit between
inefficient and efficient drilling seems to be around 3.0 hp/in2.
Experimental data shows that DSE values tend to the rock confined compressive strength (CCS) when the system is
drilling at optimum conditions. DSE has a better correlation than MSE, with the CCS. Field data also shows a good
correlation between DSE calculated with downhole data, and CCS when drilling at-balance. There is no correlation between
DSE calculated with surface data and UCS.
Both, mechanical and hydraulic component should be increased at the same time to efficiently increase ROP. Even though,
adding more mechanical energy al...
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- Spring '13