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Tomax 5 ¼” X-Series AST

The “x” means extra flexible and reflects an extensive operational capability in terms of drilling parameters and well curvature.

With its 5 ¼” OD, this tool provides for greatly improved capabilities in combination with 6 to 7 ½” drill-bits and even larger under-reamers. The tool has a torsional capacity about double that of a 4 ¾” OD tool. The stroke capacity of 10” or 0.25m gives the tool a working range that makes it an optimal solution for high load performance-drilling. Tomax can provide an adequate overshot with the tool for use in 6 and 6 ¼” hole sizes.

The pressure loss through the tool is 150 psi at 350 GPM or 10 bar at 1300 lpm.

Length6,18 m20,27 ft
Max. OD133 mm5.25”
Min. ID35 mm1.38”
Connection topNC38/HT38/XTF39NC38/HT38/XTF39
Connection bottomNC38/HT38/XTF39NC38/HT38/XTF39
Tomax anti stick slip downhole tool 5 ¼” X-Series
The 5,25 XC AST has undergone significant development efforts to produce the dynamic capacity that now makes the tool repeatedly show significant efficiency gains in unconventional wells.
Tomax 4.75 XC tool at manufactures place
The 5 ¼” X-Series is frequently delivered with XTF39 connections to provide the best fatigue resistance possible for fast rotation while steering.

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