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operations (pressure or fluid), possible of larger bore, less
tendency to bend, warp or two and less weight per foot. An
octagon-shaped kelly now on the market, but has limited
acceptance.
Although much has been done to make the kelly tougher, it
is still a rig moving headache. Nothing so useless as a bent kelly.
Because of its willow-like characteristics and length, a kelly
scabbard has been provided for its protection. Although self-
drilling scabbards are on the market, they have been deemed
impractical in many areas because surface strata has required the
use of a rock bit to drill the rathole. Nevertheless, a scabbard of
some type has been provided as a combination rathole and kelly
protector by all thoughtful contractors. This has become common
practice, just as it has to avoid breaking out the kelly with the
tongs (always on the kelly saver subs).
Thinking back through all that has been said about the kelly,
as well as the swivel and hooks, we must conclude that a dollar
spent in the right direction toward equipment suited for your
drilling needs, and time spent in protective maintenance can and
willpay cash dividends. It's guaranteed to keep it turning to the
right.

Kelly Cocks

Like insurance, the importance of the kelly cock is seldom
felt, but is invaluable in an emergency. It is an inexpensive safety
item for any size rotary rig, and should be on the same plane of
importance as the blowout preventer. Actually the kelly valve
serves the same purpose within the drill stem.
It stands as a positive shut-off valve above or below the kelly
when drill pipe is in the hole without a float, or should the float fail
when needed. It protects the rotary hose and standpipe when
pressure from a formation exceeds the input. It can, in everyday
use, save wear and tear on the rotary hose by opening the cock

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