Slip-type casing hangers provide a method to transfer the weight or tension load of a casing string to a casing head or spool. Slip-type hangers are available in automatic-sealing and manual-sealing varieties. Automatic hangers have seals which are energized by casing weight, while non-automatic hangers have seals which require means other than casing weight to be energized. Non-automatic hangers are typically used when insufficient load is available or when cementing back to the surface.
C-22 Casing Hanger
Combined in a single unit, the C-22 wrap around casing hanger incorporates packoff, slip bowl and slips. When the casing load is suspended, the packoff automatically seals the casing annulus below the slips, this providing annulus packoff before the removal of the blowout preventer.The C-22 hanger’s controlled friction reduces casing deflection, can be easily installed and is economical.
C-29 Casing Hanger
The C-29 Casing Hanger provides high hanging capacity with minimum casing deflection. When the upper slips move down and energize the pack off, the C-29’s non-tapered lower slips engage automatically and apply controlled compression. The lower slips do not move down the pipe, thus they do not create the high compressive forces, as do conventional tapered slips. The C-29 offers far less casing deflection and much greater hanging capacity than other conventional hangers.
C-21 Casing Hanger
Slip bowl and a type H pack off seal ring are all combined in the C-21 The type “H” pack off provides a positive annulus pack off after the casing
has been suspended and cut off.