Friction reducing tool
AssigneeWeatherford/Lamb, Inc.
InventorGeoffrey Neil Murray
Life of this patent
Estimating the term…
Abstract
A centralizer having a first group of rollers (5) for reducing friction between the centralizer and an oil field tubular (7) and a second group of rollers (4) for reducing friction between the centralizer and the wall of a well. The axles of the first group of rollers (5) are generally aligned with the axis of the bore (2) to reduce rotational friction. The axles of the rollers of the second group of rollers (4) are generally transversed to the bore (2). The arrangement reduces rotational and axial drag between an oil field tubular (7) and the walls of a well, particularly when initiating rotation of an oil field tubular.
Claims39
A centraliser comprising:
- a generally tubular body comprising an overhang;
- a first group of rollers rotatably secured to the body at intervals about the body and positioned to project within a bore of the body to reduce rotational drag between the body and a first tubular disposed there through;
- a second group of rollers rotatably secured about an outer periphery of the body which projects beyond the outer periphery of the body to reduce axial drag between the body and a second tubular disposed there around;
- and
- wherein the rollers further comprise a projection at each end adjacent the overhang and the rollers and body are dimensioned so that should an axle associated with a roller fail, the roller remains contained within the body.
A friction reduction tool, comprising:
- an annular body having a longitudinal bore disposed there through;
- and
- at least one roller assembly, comprising:
- one or more recesses disposed about the body;
- and
- one or more rollers each disposed about an axle, wherein the axle is connectable within the one or more recesses so that should the axle fail, the roller remains contained within the body, wherein each of the one or more rollers has a projection at each end and a recessed portion between said projection and said axle.
A friction reduction tool, comprising:
- an annular body having a longitudinal bore disposed there-through, a pedestal and an overhang on the pedestal;
- and
- at least one roller assembly, comprising:
- one or more recesses disposed about the body in the pedestal;
- one or more rollers having a projection on each end and each connectable within the one or more recesses;
- means for retaining the one or more rollers within the body;
- and
- wherein the roller projection is adjacent the pedestal overhang.
A friction reduction tool, comprising:
- an annular body having a longitudinal bore disposed there-through;
- and
- at least one roller assembly, comprising:
- one or more recesses disposed about the body;
- one or more rollers each disposed about an axle;
- one or more projections each disposed within the one or more recesses to retain the one or more rollers within the body;
- a first roller assembly having the one or more rollers each positioned to project within the bore;
- and
- a second roller assembly having the one or more rollers each positioned to project beyond an outer diameter of the body.
Dependencies are inferred from the claim text.