What is the true radius feature on the Rigger liner hanger?
Most liner hangers have a “cone” feature located on the outside surface of the liner hanger. When activated, the slips slide down over the cone and engage the casing. By definition a cone does not have a constant radius, i.e. the radius is larger at the base of the cone than at the top. To get maximum hanging capacity from the slips they must, in theory, land in a position on the cone where the radii are in complete alignment. This will transfer the load evenly to the body of the liner hanger. In actual application this is not likely due to a number of variables; slightly larger or smaller casing ID, slightly larger or smaller hanger OD, and total weight on the slips. All of these will cause the slips to engage the casing at a different location on the cone. The liner load is then transferred to “points of contact” wherever the slips come in contact with the liner hanger. This puts tremendous pressure on these points and can result in the slips failing or the liner hanger itself collap
