Secondary Seal Assemblies come in many forms and are installed in the lower seal area of the casing spool or tubing head. They are utilized to offer redundant well security between the casing annulus and the flanged connection of a casing head, casing spool or tubing head. In certain instances these seals can offer a special sealing capability for FRAC equipment. Secondary seal assemblies include several advanced elastomeric and metal to metal seal designs.
Packoffs or Secondary seals come in many different configurations and pressure ratings
Secondary seals assemblies seal on rough casing
Some provide an elastomeric seal
Some provide a metal to metal seal
Secondary seals, or packoffs, come in many different I.D. sizes allowing for a broad range of casing sizes to be utilized in a standard bottom prep in the casing spool or tubing head