Corrosion Cap
Corrosion Caps are also known as Temporary Abandonment Caps or TA Caps. They are used for suspending an offshore well at the seabed. Once an offshore well is drilled and needs to be temporarily suspended for moving the rig off location, leaving the casing or wellhead open at the seabed could allow botanical growth or corrosion of exposed threads. This could make it difficult to reconnect to the well for any future operations. Hence a Corrosion Cap is installed to protect the threads and seal areas.
Corrosion caps are installed and retrieved with a running tool. Corrosion caps can also offer pressure containment if a check valve is installed in the stem of the cap. Normally after disconnecting casing strings at MLS, the corrosion cap is installed for the topmost threads. However, caps can be installed for each casing string for isolating the string and its annular space if required.