menu toggle


Tomax 6 ¾” X-Series aST

The “X” means extra flexible and reflects an extensive operational capability in terms of drilling parameters and well curvature. This tool is the most used in the AST fleet and has an extensive service record that includes coring, milling and under-reamer operations.

The 6 ¾” X-Series AST has a stroke capacity of 8” or 0.2m and can be configured for regular vertical as well as deviated drilling. The tool is viable for operations up to 425 F (220 C) and is routinely used in HTHP operations. The ability to manage drilling vibrations and stick-slip at deep depths can be used to optimize the use of PDC type drill-bits and mud motors in hot, compacted rock.

The pressure loss through the tool is minimal (less than 30 psi at 500 GPM or 2 bar at 1900 lpm). The tool can carry electronics to measure the actual work performed downhole.

Length5.21 m17.09 ft
Max. OD171 mm6.75”
Min. ID53 mm2.08”
Connection topNC 50 boxNC 50 box
Connection bottomNC 50 pinNC 50 pin
Tomax anti stick slip downhole tool 6 ¾” X-series
Tomax 5.25 and 6.75 X Series production line
The 6 ¾” X-Series AST is the first and largest product line with Tomax. The capacity and versatility of the tool builds on ISO and API certificated standards. High capacity for parts production is the backbone of the unique reliability record.
Hight temperature drilling vibration
The need to mitigate vibrations is at its highest in extremely hot wells due to the sensitivity of the electronics close to their operational limit. The 6 ¾” XT-AST has been full-scale tested and operated at 425 F (220 C). Compare ASTs to find the rating needed.

Our products