Casing Spools Functions

The casing spool in a conventional wellhead system is the component that allows for an additional string of casing to be set in the well. Depending on the casing program for the well, there can be one or more casing spools and they perform the following functions:

• Allows for suspending the next casing string in the well
• Supports the blowout preventers (BOP’s) while drilling
• Provides outlets for fluid returns
• Provides a means to test the blowout preventers while drilling
• Has flanges on both the top and bottom of the assembly
• Has a seal area in the bottom flange for a secondary seal between the casing annulus and the flanged connection
• Utilize a test port in the bottom flange that allows for the secondary seal and the flanged connection to be pressure tested