A '
Bell nipple'' is a section of large diameter pipe fitted to the top of the
blowout preventer
A blowout preventer (BOP) (pronounced B-O-P) is a specialized valve or similar mechanical device, used to seal, control and monitor oil well, oil and gas wells to prevent Blowout (well drilling), blowouts, the uncontrolled release of crude oil ...
s that the
flow line
{{for, the molding defect, Flow marks
A flow line, used on a drilling rig, is a large diameter pipe (typically a section of casing) that is connected to the bell nipple (under the drill floor) and extends to the possum belly (on the mud tanks ...
attaches to via a side outlet, to allow the drilling fluid to flow back over the shale shakers to the
mud tanks.
See
Drilling rig (petroleum)
This article lists the main components of a petroleum onshore drilling rig.
Offshore drilling rigs have similar elements, but are configured with a number of different drilling systems to suit drilling in the marine environment.
The equipment ...
for a diagram.
Oilfield terminology
Drilling technology
Petroleum engineering
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