2021 PE Exam Comments

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Pumping: 2021 #29

A casing string is to be cemented at 10,000 ft in a well containing 10-lbm/gal mud, which will be displaced from the annulus by 500 ft of 8 lbm/gal mud flush, 1,500 ft of 12.5 lbm/gal filler cement, and 1,000 ft of 16.5 lbm/gal cement. The pump pressure (Mpsig) required to completely displace the cement from the casing with 9-lbm/gal brine is closest to: A) 1; B) 1.1; C) 1.2; D) 1.3.

Solution:
10000-500-1500-1000 = 7000 ft 9-lbm/gal.
0.052*((500*8)+(1500*12.5)+(1000*16.5)+(10*7000))=5681psig.
10,000*9=4680 psig.
5946 – 4680=1001 psig, “A”.
(TS12 P186; GB 3 HYD 2; RG P41, P67).