Additional casing run below structural casing (i.e. for shallow flow risks). Normal clearance casing OD in.: 26. Tight clearance casing OD in.: 28 or 26. NOTE These are examples only. Each well can have variations in number of casing strings and sizes. Naming conventions can vary. The heavy-wall surface casing designs may allow 13 5/8 in. to be run as a liner and not tied back.
Source: API RP 96, Deepwater Well Design and Construction, First Edition, March 2013. Global Standards
tubular pipe extending upward from or beneath the sea floor containing pipes that extend into the petroleum reservoir
Source: ISO 19900:2013, Petroleum and natural gas industries – General requirements for offshore structures. Global Standards
(a) means material used or placed in position for the conveyance of electricity; but
(b) does not include the wire of an electric fence.
Source: Health and Safety in Employment (Mining—Underground) Regulations 1999, SR 1999/331, New Zealand, as of 8 October 1999. Regulations