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Well Kill, Kick Detection, and Well Shut-In                  255


              (5731 psi) minus the hydrostatic head of fluid in both the tubing and
              annulus. In this example the main steps are:
             •  Tubing filled with the original annulus (packer) fluid.
             •  Kill fluid filling annulus to the sliding sleeve.
             •  Full circulation (well dead).


              7.3.8.4 Begin kill
              With SSD open. Casing pressure applied, but no fluid pumped:
             •  Pressure at SSD: 5731 psi. This pressure must be maintained
                throughout the kill.
             •  SITP 2126 psi.
             •  SICP 375 psi.
                 Open the choke and begin to pump kill fluid at the slow
              circulation rate.



              7.3.8.5 Tubing filled with annulus (packer) fluid
             •  With annulus (packer) fluid to surface the tubing pressure required to
                maintain overbalance will be:
                •  5731 2 (10,300 3 0.52) 5 375 psi.
             •  After pumping the tubing volume (218 bbls) annulus (packer) fluid
                will reach surface. At this point the kill fluid/packer fluid interface
                depth in the annulus is the volume pumped divided by the annulus
                capacity: 218(bbls) 4 0.0414 bbls/ft 5 5265.7 ft. This leaves 10,300 2
                5265.7 5 5034.3 feet of packer fluid remaining in the annulus.
             •  Annulus HP (to SSD)
             •  5034.3 3 0.52 5 2618 psi.
             •  5265.7 3 0.5564 5 2930 psi.
             •  Casing   head    pressure  to   maintain  overbalance:  5731
                (2618 1 2930) 5 183 psi.
                 As the casing fills with kill weight fluid, the pressure can be stepped
              down from 375 to 183 psi. This is best done in stages. The choke opera-
              tor should be provided with a schedule showing casing pressure versus
              volume (or strokes). In this example, after pumping 218 bbls, the pressure
              should have been reduced by 192 psi, or 1 psi for every 1.135 bbls
              pumped, or 0.881 psi/bbls. Casing pressure would continue to be stepped
              down until the annulus is filled with kill fluid (Table 7.3).
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