Downhole Tool
A downhole tool is any device run into a wellbore on drill pipe, tubing, coiled tubing or wireline to drill, complete, measure, stimulate or repair the well. Categories include drilling tools (bits, mud motors, stabilizers, jars, reamers), measurement tools (MWD, LWD and wireline logging), completion equipment (packers, sliding sleeves, landing nipples, subsurface safety valves), artificial lift equipment and fishing tools for retrieving lost objects. Downhole tools must withstand high pressure, high temperature, abrasive or corrosive fluids, shock and vibration within a restricted diameter. Relevant standards include API Spec 7-1 for rotary drill stem elements, API Spec 11D1 (ISO 14310) for packers and bridge plugs, and API Spec 14A for subsurface safety valves. Selection parameters include outside and inside diameter, connection type, pressure and temperature rating, metallurgy and expected well conditions.
Examples
- Retrievable production packer in a completion string
- Hydraulic drilling jar in the bottomhole assembly
- MWD tool transmitting directional data while drilling