Casing is a large-diameter pipe that serves as the structural retainer for the walls of
oil and gas wells, or wellbore. It is inserted into a well bore and cemented in place
to protect both subsurface formations and the wellbore from collapsing and to allow
drilling fluid to circulate and extraction to take place.
O.D. | Nominal | O.D. | W.T. | Nominal | Type of pipe end | ||||||||
Weight | Weight | Grade | |||||||||||
(lb/ft) | (kg/m) | J-55 | L-80 | N-80 | C-90 | ||||||||
In. | mm | In. | mm | H-40 | K-55 | M-65 | C-95 | Type1,Q | T-95 | P-110 | |||
18 5/8" | 87.50 | 18.625 | 473.08 | 0.435 | 11.05 | 130.21 | PS | PSB | PSB | -- | -- | -- | -- |
P - Plain; S - Short round thread; L - Long round thread; B - Buttress thread |