Tubular goods can get stuck down hole for many reasons. Listed here are some of the most common causes or types of sticking, after which follows a discussion of each condition.

Sand Sticking – This condition can occur with tubing, drill pipe, or casing.

Mud sticking – This type of sticking is generally encountered with tubing in a cased hole, and also occurs with drill pipe and casing.

Mechanical Sticking – There are several types of mechanical sticking such as:

  • Stuck packers or other downhole assemblies.
  • Multiple strings (wrap around) normally tubing.
  • Crooked pipe – usually caused by dropping of pipe – either by pulling into or malfunction of elevators, etc.
  • Junk in hole – any foreign object dropped in hole that cannot by-pass collars, tool joints or bottom hole assembly.

Key Seat Sticking – This occurs in an open hole when drilling either a directional well, or a well that deviates from true vertical.

Sloughing Hole Sticking – Here’s a problem encountered in drilling through heaving shale or other formations that have a tendency to break off and fall in the bore hole. The formation lodges around tool joints, stabilizers or drill collars.

Under-gauge Hole Sticking – This type of sticking occurs when a shale formation deforms, a salt that has tendency to flow, or a bit that is worn on the O.D. by abrasive sand.

Differential Sticking – Pipe can get stuck in an open hole when the pipe string comes in contact with a permeable formation of lesser pressure than the hydrostatic pressure of the drilling fluid.

Blow-out Sticking – When underground pressure exceeds the existing hydrostatic pressure of the well fluid, it can cause sand, shale, other formations and even pipe protector rubbers to be blown up the hole, bridge over and string of pipe.

Cemented Sticking – Cementing may cause stuck pipe when there is a mechanical malfunction, human error, a lost circulation problem or during cementing to contain a blowout.

Lost Circulation Sticking – This is an occurrence that normally react to hole sloughing or well blowouts.