Abstract: Apparatus for reducing torque on a drill string includes a first bearing assembly, a second bearing assembly, and a bearing sleeve. The first and second bearing assemblies are disposed on and clamped onto a tubular portion of a drill pipe of the drill string, and each include a first and second section. The bearing sleeve is disposed on the drill pipe such that the bearing sleeve is maintained in an axial position relative to the drill pipe by the first bearing assembly and the second bearing assembly. Each of the first and second bearing assemblies have a first diameter portion and a second diameter portion that is smaller than the first diameter portion. The second diameter portion of the first bearing assembly and the second diameter portion of the second bearing assembly are disposed adjacent to each other and the bearing sleeve is disposed around the adjacent second diameter portions.

Abstract: Apparatus, methods, and systems for preconditioning and/or testing a centralizer, and a preconditioned centralizer, are provided. The apparatus includes a restrictor positionable around a tubular and having an inner diameter that is greater than an outer diameter of the tubular. The apparatus also includes a driver configured to translate the restrictor relative to the tubular in at least a first axial direction. The restrictor is configured to engage a centralizer attached to the tubular, and the restrictor is configured to at least partially collapse flexible ribs of the centralizer when the driver axially translates the restrictor across at least a portion of the flexible ribs.

Abstract: Apparatus for reducing torque on a drill string includes a first bearing assembly, a second bearing assembly, and a bearing sleeve. The first and second bearing assemblies are disposed on and clamped onto a tubular portion of a drill pipe of the drill string, and each include a first and second section. The bearing sleeve is disposed on the drill pipe such that the bearing sleeve is maintained in an axial position relative to the drill pipe by the first bearing assembly and the second bearing assembly. Each of the first and second bearing assemblies have a first diameter portion and a second diameter portion that is smaller than the first diameter portion. The second diameter portion of the first bearing assembly and the second diameter portion of the second bearing assembly are disposed adjacent to each other and the bearing sleeve is disposed around the adjacent second diameter portions.

Abstract: Apparatus, methods, and systems for preconditioning and/or testing a centralizer, and a preconditioned centralizer, are provided. The apparatus includes a restrictor positionable around a tubular and having an inner diameter that is greater than an outer diameter of the tubular. The apparatus also includes a driver configured to translate the restrictor relative to the tubular in at least a first axial direction. The restrictor is configured to engage a centralizer attached to the tubular, and the restrictor is configured to at least partially collapse flexible ribs of the centralizer when the driver axially translates the restrictor across at least a portion of the flexible ribs.

Abstract: An apparatus according to one or more aspects of the present disclosure comprises at least two centralizers, each centralizer having a circumferential stand-off portion and a second circumferential portion defining 360 degrees, at least two bows extending between opposing collars within the stand-off circumferential portion; wherein the at least two centralizers are spaced axially apart and fixedly attached to the tubular with the respective circumferential stand-off portions angularly offset from one another to provide 360 degrees of standoff. According to one or more aspects of the present disclosure, one or both of the collars of each centralizer may be rotationally stationary relative to the tubular and axially moveable relative to the tubular.