
300
O
Opening Ratio
Opening Ratio: The ratio of the pressure required to open the preventer to
the pressure under the rams.
Open Shoe: An external annulus (production by surface casing, e.g., in
which the cement behind the production pipe has not been brought up into
the casing-by-casing annulus). The annulus is open to the formation into
which the outer string has been set.
Operable Capacity: (1) The amount of capacity that, at the beginning of
the period, is in operation, not in operation and not under active repair but
capable of being placed in operation within 30 days, or not in operation but
under active repair t