A float collar and shoe are components of a casing string used in oil and gas drilling operations. They are designed to provide buoyancy to the casing string, allowing it to be installed more easily and accurately in the wellbore.
The float collar is located near the bottom of the casing string and includes a built-in check valve that allows fluid and cement to flow down into the annulus between the casing and the wellbore. The float collar also contains a metal ball that can be used to prevent reverse flow during cementing operations.
The float shoe, located at the bottom of the casing string, also includes a check valve to allow fluid and cement to flow into the annulus. It is designed to provide additional support and stability to the casing string as it is being installed, helping to prevent buckling, bending, or damage to the casing.
The float collar and shoe can be made from a variety of materials, including cast iron, steel, or aluminum. They may also be lined with materials such as urethane or rubber to provide additional resistance to wear and fluid flow.
Overall, the float collar and shoe are essential components of a casing string, providing buoyancy, support, and stability during oil and gas drilling operations.