Cement: 2005 #73 (similar)

Time for a simple cement calculation problem. Using random numbers:

16" 65 lbm/ft casing set to 2,000 ft in 20" hole (float collar 100 ft above float shoe).
Use cement with a yield of 1.32 cf/sack. Slurry sacks w/ 5% excess?

Use the Redbook for 20/16 hole/casing for 0.7854 cf/ft.
Annulus cf: 0.7854 cf/ft(1.05 excess)2,000 ft = 1,649 cf.
1.2684 cf/ft(100 ft) = 127 cf.
Total = 1,776 cf/1.32 cf/sack = 1,346 sacks (round up).

Note that if using a log to locate surface water for regulatory reasons any water signature on the resistivity curve must be considered "water" (to be conservative). For example, if there was a dip in resistivity in a 1,500 to 1,550 sand, you would have to use 1,550 ft as the lower boundary of the sand.