Page 113 - Well Control for Completions and Interventions

Completion Equipment 105

3.4.1 The liner hanger
A liner hanger, as the name suggests, secures and supports the liner. It
uses mechanical slips to grip the inside of the casing a pre-determined
distance above the casing shoe. The space between the liner hanger and
the casing shoe is called the liner lap. Liner hangers can be set hydrauli-
cally, mechanically, or a mixture of the two. Most liners are cemented
back to the liner hanger. Some systems are designed to allow liner rota-
tion after the hanger is set as the ability to rotate has been shown to
4
improve cement bond, particularly in long high angle wells. The price
of having improved cement integrity is a mechanically more complex
hanger system.
Some liner hanger systems have a polished bore receptacle (PBR)
above the liner hanger. This enables the base of the production tubing to
be stabbed into the liner top, providing both a seal and a continuous con-
duit for produced fluids (Fig. 3.15).

Figure 3.15 Weatherford rotatable liner hanger with integral liner top packer.