• Pressure Balanced Drilling Bumper Sub


    The Bowen Pressure Balanced Drilling Bumper Sub is a long stroke bumper sub often called a slack joint. It is engineered to withstand sustained torque through its full five-foot stroke under the most severe drilling operations. Pressure Balanced Bumper Subs may be used as motion compensators on floating rigs, or to allow controlled feed-off on delicate fishing or milling operations.


    • Completely pressure balanced
    • Free travel through the full stroke
    • Unaffected by variations in pump pressure
    • Unaffected by hydrostatic pressure
    • Bore through the tool permits full circulation at all times



    The Pressure Balanced Drilling Bumper Sub is approximately 36 feet long and is available in sizes with minimum outside diameters of 4-3/4, 6-1/4 and 7-3/4 inches. The tool O.D.'s are variable as ordered and each is manufactured with an O.D. that matches the drill collar or tool joint O.D. of the drill string in which it will be used.

    How to Order


    • Outer Diameter
    • Connections
    • Bottom hole temperature