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Threaded Ring
ReedHycalog®'s Threaded Ring cone retention system was designed specifically to improve bearing durability
and reliability and minimize the risk of losing cones. Because all ReedHycalog
Sabre™ and TuffDuty™ bits greater
than 8 1/2" in diameter use Threaded Ring cone retention to minimize the risk of cone loss.
Rock bit cutters, which have the Threaded Ring system, are retained a two-piece solid ring of steel which is
threaded and permanently locked into the cutter after assembly so it cannot fall out. Unlike simple snap rings,
the solid ring becomes an integral part of the cone itself.
The Threaded Ring system has a large area of engagement between the lug and cutter. Should a seal failure occur,
drilling mud and abrasives can enter the bearing resulting in accelerated wear of the retention system. Since
the Threaded Ring cannot fall out, as ball bearings often do, the driller has more time to identify bit trouble.
Threaded Rings provide more than just better cone retention. The Threaded Ring’s superior axial bearing surface
overcomes many of the performance problems inherent in ball bearing designs. As rock bits drill, cutters are
continually thrust inward and outward by impact with the formation. Ball bearings generate concentrated loads
at the ball contact points, leading to spalling, the flaking of small fragments from the ball failure.
Additionally, the superior design of the Threaded Ring system reduces axial play so the cutter does not rock back
and forth as it does with floating ball bearings. This not only more uniformly distributes the bearing load, but
also minimizes grease pressure fluctuations, resulting in longer seal life.
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