If a 10,000 ft drillstring’s frictional pressure loss is 1,433 psi, and the 12 lbm/gal mud returns fill a 10 ft x 10 ft tank at 6-1/2 inches per minute, the pressure at the base of the drill collar is closest to? The ID of the drill collars is 2.5 in and pump pressure is 3,000 psi. A) 7825 B) 7819 C) 7813 D) 7800.
This problem is solved using the standard mechanical energy balance equation. Note the only source truly needed to solve it is the SPE Reference (to calculate the pressure from gravity). If you don't include the KE effect will be off just slightly. Note KE is generally ignored in the field but don't dare ignore it on the exam and this problem shows how will get the wrong answer if you do (even though you don't need to know precisely what the KE value it is to get it right, just that it's there).
Sources: SPE Reference, Guidebook 8 FAC 6, TS2 P129.
Hi David,
ReplyDeleteI have been trying to get the practice exams digital edition in Nigeria and I cant. Is there any other way to get it?
Where would one find the calculation to solve for Vdc? Also, could you please show the steps how to solve this using what im assuming is Bernoulli's equation on page 146 of the reference guide? The solution in the kindle uses forms of equations that aren't in the reference guide.
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