Abstract: A rotatable element for an earth-boring tool in a subterranean borehole includes a rotatable element and a stationary element. The rotatable element and stationary element include a seal arrangement between the rotatable element and the stationary element. The seal arrangement encloses a volume that remains substantially constant as the rotatable element moves relative to the stationary element.

Abstract: Rotatable elements for use with earth-boring tools include a movable element and a stationary element. The movable element and stationary element include an index positioning feature that is configured to rotate the movable element as the movable element moves between a first axial position and a second axial position.

Abstract: A cutting element assembly includes a sleeve, a rotatable cutting element disposed within the sleeve, and a retention element. The sleeve and rotatable cutting element each have frustoconical surfaces. In some embodiments, a rotatable cutting element defines a first generally cylindrical surface, a second generally cylindrical surface, and an axial bearing surface opposite the end cutting surface and intersecting each of the first generally cylindrical surface and the second generally cylindrical surface. A bearing element may be disposed between an upper surface of a sleeve and a bearing surface of the rotatable cutting element. Earth-boring tools having rotating cutting elements are also disclosed.

Abstract: A rotatable cutter may comprise a rotatable element, a stationary element, and a releasable interface. The releasable interface may be configured to substantially inhibit rotation of the rotatable element when the rotatable element and the stationary element are at least in partial contact. An earth-boring tool may include one or more rotatable elements.

Abstract: A cutting element assembly includes a rotatable cutting element, a sleeve having a cutter receiving aperture extending at least partially through the sleeve and configured to receive at least a portion of the rotatable cutting element within the cutter-receiving aperture, and a retention element rotatably coupling the rotatable cutting element to the sleeve. In some embodiments, the retention element includes a pin extending from a base portion of the sleeve and having at least one resilient portion having at least one protrusion radially extending outward. In additional embodiments, the retention element include a split ring or O-ring disposed within a groove of the rotatable cutting element. Earth-boring tools having rotating cutting elements are also disclosed.

Abstract: An earth-boring tool comprising a bit-body, a blade, and a cutting element assembly. The cutting element assembly comprising a journal, a rotatable cutting element, and a retention element. The journal defines an upper cylindrical exterior surface, a first bearing surface that intersects the upper cylindrical exterior surface, and a first external groove in the upper cylindrical exterior surface. The rotatable cutting element comprises a table of polycrystalline hard material having an end cutting surface and a supporting substrate. The substrate defines a second bearing surface, a longitudinally extending blind hole having a diameter larger than the diameter of the upper cylindrical exterior surface of the journal, and a second groove in the surface of the substrate defining the blind hole. The retention element is disposed at least partially in the first groove and partially within the second groove.

Abstract: Rotatable cutting elements for earth-boring tools may include a substrate and a polycrystalline, superabrasive material secured to an end of the substrate. A sleeve may be sized and shaped to circumferentially surround at least a portion of the substrate. Rollers may be sized and shaped for positioning between, and making rolling contact with, the substrate and the sleeve, the rollers configured to rotate relative to the substrate and the sleeve and to enable the substrate to rotate relative to the sleeve. The rollers may be configured to bear at least radial forces acting on the substrate and the sleeve.

Abstract: A cutter assembly, which may include a rotatable cutting element disposable within a pocket of an earth-boring tool, a sleeve configured to receive the rotatable cutting element, and at least one retention mechanism configured to secure the rotatable cutting element within the sleeve. The rotatable cutting element may include a substrate, a table, which may be comprised of a superhard, polycrystalline material disposed on a first end of the substrate, and a recess extending into a second, opposite end of the substrate. The sleeve may comprise at least one radial bearing surface, a backing support sized, shaped, and positioned to extend into the recess of the rotatable cutting element, and at least one axial thrust-bearing surface located on the backing support and positioned to contact the substrate within the recess.