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Tomax 4 ¾” X-Series aST

The “X” means extra flexible and the 4 ¾” OD tool has a comprehensive service history from both multi-lateral producers and exploratory work.

The 4 ¾” X-Series AST has a stroke capacity of 10” or 0.25m and can be configured for all regular drilling operations including work with motors and under-reamers. For extended laterals, the tool can also be configured to better capture and preserve the weight coming through and produce a more constant push on the bit. For vertical drilling, the 4 ¾” X-Series AST not only prevents harmful stick-slip and drilling vibrations, but it also provides a safer way of operating sensitive, tapered drill-strings.

The inner diameter is 1 ½”, which presents no restrictions to relevant drop-balls. The pressure loss through the tool is 150 psi at 350 GPM or 10 bar at 1300 lpm. The tool can also be configured for high temperatures.

Length5.49 m18.01 ft
Max. OD121 mm4.75”
Min. ID35 mm1.38”
Connection topNC 38 boxNC 38 box
Connection bottomNC 38 pinNC 38 pin
Tomax anti stick slip downhole tool 4 ¾” X-series
The 4 ¾” X-Series presents an exceptional stroke to provide steady loading of the bit even with significant axial stiction in slim laterals.
Image of 4 ¾” X-Series AST High Torque (HT 38) connections Tomax
The 4 ¾” X-Series AST has High Torque (HT 38) connections as an option. Based on its torsional capacity and ability to predictably absorb peak loads the tool can provide a great safety improvement when used as a torsional buffer to protect less capable connections further down in the BHA.

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