Definition - What does Wellhead Adapter mean?
Wellhead Adapter is a component that is connected to the wellhead to fix the pressure measurement and control equipment. Wellhead adapters provide a direct and secure connection and access point to all the pressure control equipment with the wellhead. These adapters are available in flange and threaded forms. Wellhead adapters can also be used as pressure transmitters to gauge local and remote pressure indications.
Petropedia explains Wellhead Adapter
During the drilling of an oil or gas well, a wellhead is used to provide pressure seals to casing strings that run from the surface to the bottom of the wellbore. The wellhead is the component which is welded to the casing string at the surface to provide a means for the pressure inside the well to be measured and controlled. A wellhead adapter is connected to the wellhead through which the pressure measurement and control equipment are connected with the wellhead. The adapter provides a means of pressure sealing between the casings and enables a Christmas tree to be attached when production operations are ongoing.