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Tomax 9 ½” X-Series aST

The “X” means extra flexible and reflects an extensive operational capability in terms of drilling parameters and well curvature. This is the largest OD tool in the fleet.

The tool is designed for top-hole drilling as well as directional work in hole sizes down to 12 ¼” due to its high bending capacity. The 9 ½” tool is internally characterized by its massive helix section that provides for safe transformation of impact loads when mitigating vibrations and stick-slip from large diameter reamers and hole-opener wings from floating rigs and drillships.

The 9 ½” tool can be configured for very high continuous torsion and compression load. The inner diameter is 2,83” and presents no restrictions to drop-balls. The pressure loss through the tool is minimal (less than 30 psi at 1200 GPM or 2 bar at 4500lpm).

Length5.00 m17.85 ft
Max. OD241 mm9.5”
Min. ID72 mm2.83”
Connection topAPI 7 5/8 REG boxAPI 7 5/8 REG box
Connection bottomAPI 7 5/8 REG pinAPI 7 5/8 REG pin
Tomax anti stick slip downhole tool 9 ½” X-series
The 9 ½” X-Series AST is the largest tool in the fleet. It capability makes it a perfect solution to speed up top-holes and drilling operations that uses large under-reamers.
Oilwell drilling is frequently undertaken in areas where the drill-bit is at risk from unpredictable ocean conditions combined with contrasting underground sediments. The 9 ½” XC-AST is called to all ends of the world to reduce risk and save time in such operations.

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