For annular gaskets for emergency stop flow at underwater oil well to function, the blow out preventer,BOP, must be removed to expose the well shaft. Damaged drill string or debris must also be removed from the well using drill head or other means. This design is based on the annular blow out preventer that normally sits at the top of the main blow out preventer where the riser is connected. Annular gaskets are installed along the length of the emergency stop flow drill string at intervals and span as necessary to reduce upward pressure sequentially. Gasket is made of rubber designed to expand when hydraulic rams squeeze it to cut off the flow of oil. Gaskets must be closed sequentially to ease pressure to a stop. Design of drill string is typical to allow the use of fill mud or concrete to fill and close well. Drill string must be forced down through upward flow pressure, so its design must allow for oil and gas to continue to flow until drill string is deep enough for gaskets to be effective. Gaskets will also aid in maintaining the drill string center within the damaged well.
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