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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).