Abstract: A non-rotating downhole sleeve adapted for casing centralization in a borehole. The sleeve includes a tubular body made of hard plastic with integrally formed helical blades positioned around its outer surface and an inner surface which allows drilling fluid to circulate to form a non-rotating fluid bearing between the sleeve and the casing. The tubular sleeve comprises a continuous non-hinged wall structure for surrounding the casing. The non-rotating centralizer sleeve reduces sliding and rotating torque at the surface while drilling the casing, for example, with minimal obstruction to drilling fluid passing between the casing and the surrounding borehole.

Abstract: A non-rotating downhole sleeve adapted for open hole drilling and/or casing centralization. The sleeve includes a tubular body made of hard plastic with integrally formed helical blades positioned around its outer surface and an inner surface configuration which allows drilling fluid circulation to form a non-rotating fluid bearing between the sleeve and the drill pipe or casing. The helical blades reduce sliding and rotating torque while drilling, with minimal obstruction to drilling fluid passing through the borehole between the blades.

Abstract: A non-rotating drill pipe protector sleeve is molded in situ around a drill pipe tubing. The inner surface of the molded protector sleeve can be shaped to form a fluid bearing during use. Fixed stop collars may be molded in situ in the same mold and bonded to the tubing at opposing ends of the molded sleeve. Alternatively, a flexible sleeve liner made from a material having a hardness less than that of the sleeve's molding material can be used as a mold insert around the tubing. The liner can be bonded to the molded sleeve material when the sleeve is molded around the liner. The interior surface of the liner can be shaped to form a fluid bearing for the inside surface of the molded sleeve. Reinforcing inserts and wear pads can be placed in the mold region of the sleeve. Chemical and/or mechanical bonding is provided between the liner reinforcement and the material from which the sleeve is molded. Reinforcing inserts and wear pads also can be placed in the mold regions for the stop collars.

Abstract: A non-rotating downhole sleeve adapted for casing centralization in a borehole. The sleeve includes a tubular body made of hard plastic with integrally formed helical blades positioned around its outer surface and an inner surface which allows drilling fluid to circulate to form a non-rotating fluid bearing between the sleeve and the casing. The tubular sleeve comprises a continuous non-hinged wall structure for surrounding the casing. The non-rotating centralizer sleeve reduces sliding and rotating torque at the surface while drilling the casing, for example, with minimal obstruction to drilling fluid passing between the casing and the surrounding borehole.

Abstract: A non-rotating downhole sleeve adapted for open hole drilling and/or casing centralization. The sleeve includes a tubular body made of hard plastic with integrally formed helical blades positioned around its outer surface and an inner surface configuration which allows drilling fluid circulation to form a non-rotating fluid bearing between the sleeve and the drill pipe or casing. The helical blades reduce sliding and rotating torque while drilling, with minimal obstruction to drilling fluid passing through the borehole between the blades. In one embodiment, improvements are provided during casing exit when drilling in open hole environments. In another embodiment, improvements are provided in the sleeve's resistance to compressive loading.

Abstract: An attachment and fastener system rigidly secures a rotatable drill pipe protector (RDPP) to a drill pipe. The RDPP comprises a sleeve which is split axially along at least one side. Parallel hinge bars are contained in first and second hinge sections which wrap around the hinge bars along opposite sides of the opening in the RDPP. One hinge bar is rotatable in the first hinge section. A series of axially spaced apart bolts are held in corresponding threaded openings in the rotatable hinge bar which rotates about its axis to swing the bolts in unison between open and closed positions. The other hinge bar has a series of threaded receptor openings facing outwardly from slotted openings in the second hinge section and aligned with the bolts on the other hinge bar. The rotating hinge bar swings the bolts into alignment with the slotted openings in the other hinge, after which the bolts are tightened in the threaded receptor openings for applying a holding force around the drill pipe.

Abstract: An attachment and fastener system rigidly secures a rotatable drill pipe protector (RDPP) to a drill pipe. The RDPP comprises a sleeve which is split axially along at least one side. Parallel hinge bars are contained in first and second hinge sections which wrap around the hinge bars along opposite sides of the opening in the RDPP. One hinge bar is rotatable in the first hinge section. A series of axially spaced apart bolts are held in corresponding threaded openings in the rotatable hinge bar which rotates about its axis to swing the bolts in unison between open and closed positions. The other hinge bar has a series of threaded receptor openings facing outwardly from slotted openings in the second hinge section and aligned with the bolts on the other hinge bar. The rotating hinge bar swings the bolts into alignment with the slotted openings in the other hinge, after which the bolts are tightened in the threaded receptor openings for applying a holding force around the drill pipe.

Abstract: A non-rotating drill pipe protector sleeve is molded in situ around a drill pipe tubing. The inner surface of the molded protector sleeve can be shaped to form a fluid bearing during use. Fixed stop collars may be molded in situ in the same mold and bonded to the tubing at opposing ends of the molded sleeve. Alternatively, a flexible sleeve liner made from a material having a hardness less than that of the sleeve's molding material can be used as a mold insert around the tubing. The liner can be bonded to the molded sleeve material when the sleeve is molded around the liner. The interior surface of the liner can be shaped to form a fluid bearing for the inside surface of the molded sleeve. Reinforcing inserts and wear pads can be placed in the mold region of the sleeve. Chemical and/or mechanical bonding is provided between the liner reinforcement and the material from which the sleeve is molded. Reinforcing inserts and wear pads also can be placed in the mold regions for the stop collars.