Hydraulic under-reamer

The Reservoir Group Hydraulic Under-Reamer is designed to clean or remove cement scale and other material from the inside diameter of down-hole tubulars.

Hydraulic-under-reamerThe tool is mostly Ran In Hole (RIH) dually in the collapsed position.  Once the desired depth is reached, increasing the pump rate through the tool will expand the blades to the correct diameter.  Maintaining this flow rate through the tool maintains the blades at the expanded diameter.

 Once the clean out job has successfully been completed, reducing the pump rate will allow the blades to collapse back into the body.


Design Features

  • Positive Blade Retraction & Expansion; This Allows Pumping at a Reduced Rate While Running in Hole
  • Tool Design Allows Reaming in Either Direction
  • Fluid Can be Directed Onto Each Blade Through Inter-Changeable Nozzles to Ensure Positive Flushing Action
  • Blades Are Linked Together Preventing Independent Movement Which Detracts From the Clean Out Performance of the Tool
  • Pressure-Retaining Fluid Path Through the Tool to Additional Stages & Through the Bit
  • Pressure Drop Function Provides Surface Indication That the Blades are Fully Expanded


Tool Specifications

Tool O.D. 1-11/16" 2-1/8" 3-3/8" 5"
Connections 1" AMT 1½" AMT 2-3/8" REG 2-7/8" REG
Typ Pressure Drop 300 psi 400 psi 200 psi 750 psi
Max Blade Diameter 3½" 4¼" 6¼" 11"
Tensile Yield 63,000 lbs 105,000 lbs 201,000 lbs 494,000 lbs
Torsional Yield 930 ft-lbs 1625 ft-lbs 3500 ft-lbs 13,000 ft-lbs