Casing hanger

In petroleum production, the casing hanger is that portion of a wellhead assembly which provides support for the casing string when it is lowered into the wellbore. It serves to ensure that the casing is properly located. When the casing string has been run into the wellbore it is hung off, or suspended, by a casing hanger, which rests on a landing shoulder inside the casing spool. Casing hangers must be designed to take the full weight of the casing, and provide a seal between the casing hanger and the spool.

Casing Hangers may also be suspended within the wellhead by means of radial distortion of the wellhead bore e.g. the "Pos-Grip" method. This is installed to support the individual casing strings in the well. It is the landing base or the casing head. This is usually welded or screwed to the top of the surface casing string. The surface casing serves as a foundation pile for the well which transfers the hanging load to the earth. The casing head is prepared with a bowl into which the slips sit and chuck the casing in place. Most casing heads allow for the pressure readings to be taken on the annulus and provide the means to pump out or into if necessary. The top of the casing string and annulus is usually sealed.

The most common size of casing hanger is 13-3/8" with over 155,000 such units installed worldwide in 2014 alone.

The contraction of the oilfield industry throughout 2015 meant that this figure was reduced somewhat to just under 120,000 units.

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