Page 130 - Well Control for Completions and Interventions

122 Well Control for Completions and Interventions

3.15 SLIDING SLEEVES

A sliding sleeve allows communication between tubing and annulus,
and is usually opened and closed mechanically, using wireline or coiled
tubing deployed tools. Common uses of sliding sleeves are:
• To circulate a light fluid into the tubing before producing the well.
• To circulate kill fluid into the well.
• To allow production or isolation of each zone in a single string multi-
zone completion.
It is common to have a nipple profile built into the top of the sliding
sleeve. This can be used to install a straddle if a sleeve is leaking. It can also
be used to locate plugs, hang gauges, or install a choke to control flow. In
some completions, a sleeve is run immediately above the packer and used to
circulate fluids. This practice has been discontinued by most completion
engineers, and for a very good reason. Over time the sleeve can, and often
does, begin to leak. The result is a live annulus. Added to this obvious prob-
lem is a tendency for the sleeve to stick in the closed position after a pro-
longed period in the well. Gaining a circulation path before a workover is
now more commonly achieved by punching a hole in the tubing (Fig. 3.29).

Figure 3.29 Sliding sleeve.