Blind Rams
Its ends do not fit around the drill pipe but seal against each other and shut off the space below completely.
Blind rams. Variable bore rams inc. Blind ram an integral part of a blowout preventer which serves as the closing element on an open hole. Blind rams with a built in cutting edge that will shear tubulars that may be in the hole thus allowing the blind rams to seal the hole.
A thick heavy steel component of a conventional ram blowout preventer in a normal pipe ram the two blocks of steel that meet in the center of the wellbore to seal the well have a hole one half of the hole on each piece through which the pipe fits the blind ram has no space for pipe and is instead blanked off in order to be able to close over a well that does not contain a drillstring. Used primarily in subsea systems. Shearing blind rams are designed to cut through drill pipe and shut in a well control situation.
Api rp 59 recommended practice for well control operations second edition may 2006. Pipe rams close around a drill pipe restricting flow in the annulus ring shaped space between concentric objects between the outside of the drill pipe and the wellbore but do not obstruct flow within the drill pipe. Carries bore ram sizes from 7 1 16 inches to 21 1 4 inches for continue reading shearing blind rams.
Shearing blind rams blind shear rams are designed to completely seal off a well after the pipe is cut or sheared controlling pressure. Rams or ram blocks are of four common types. A combination make break power tong pipe spinner and vertical snubber is attached to the top of the unit by hydraulic jacks.
The upper ram features a v shaped cutting edge and the lower ram has a straight cutting edge.
