Abstract: A torque resistant casing scraper for attachment to a drillstring is comprised of a one piece tool body having rotationally unrestrained two-piece blade carriers with hardened diamond-shaped cutting blades and rotationally unrestrained two-piece axial centralizers. Adjoining blade carriers and centralizers rotate independently of the drillstring and the blade carriers interlocked to prevent relative rotation between the blade carriers and to index, or orient the cutting blades as desired along the longitudinal axis of the casing scraper. The diamond-shaped cutting blades and the indexed blade carriers allow both right-handed and left-handed drillstring rotation without reducing utility or effectiveness of the scraper. The casing scraper is particularly effective for deep, near-horizontal wellbores.

Abstract: A modular junk basket assembly adapted for attachment to a wellbore tubing string comprises a tubular body having a plurality of debris ports that feed into an integrally formed basket space. A baffle is slidably mounted on the tubular body which translates along the length of the tubular body to a position behind the debris ports, relative to the fluid pressure created on the baffle. The baffle has a plurality of fluid passageways which allow passage of drilling fluid and small debris as larger debris is diverted toward the debris ports and into the debris basket.

Abstract: A back-up ring for use in a liner top test tool for testing casing integrity in a wellbore is disclosed. The back-up ring is comprised of first and second ring elements that are biased apart by a compression springs. The first ring element has a plurality of radially extending flanges that cover a plurality of channels in the second ring element when the back-up ring is compressed against a seal element on the liner top test tool to seal the wellbore casing.

Abstract: A torque resistant casing scraper for attachment to a drillstring is comprised of a one piece tool body having rotationally unrestrained two-piece blade carriers with hardened diamond-shaped cutting blades and rotationally unrestrained two-piece axial centralizers. Adjoining blade carriers and centralizers rotate independently of the drillstring and the blade carriers interlocked to prevent relative rotation between the blade carriers and to index, or orient the cutting blades as desired along the longitudinal axis of the casing scraper. The diamond-shaped cutting blades and the indexed blade carriers allow both right-handed and left-handed drillstring rotation without reducing utility or effectiveness of the scraper. The casing scraper is particularly effective for deep, near-horizontal wellbores.