4.6 A casing string is to be cemented in place at a depth of 10,000 ft. The well contains 10-lbm/gal mud when the casing string is placed on bottom. The cementing operation is designed so that the 10-lbm/gal mud will be displaced from the annulus by (1) 500 ft of 8.5-lbm/gal mud flush, (2) 2,000 ft of 12.7-lbm/gal filler cement, and (3) 1,500 ft of 16.7-lbm/gal high-strength cement. The high- strength cement will be displaced from the casing by 9-lbm/gal brine. Calculate the minimum pump pressure required to completely displace the casing. Assume no shoe joints are used. Answer: 1,284 psig.