Service induced defects in used tubing fall into identifiable patterns; requiring different inspection techniques for each if ultimate accuracy is desired.

Corrosion Pitting

This is the most common used tubing defect. It may occur on either the inside or outside surface of the tube and may cover the entire length of the pipe or exist only in an isolated area.

Mechanical Damage

Routine handling of the pipe can frequently cause mechanical damage. This is particularly common in the slip areas where it can become mashed, causing ID restrictions.

Rod Wear

The vertical movement of sucker rods inside the tubing often wears a longitudinal groove into the inside tube wall. Rod wear in pumping wells can produce costly failures.

Erosion

The inside diameter of the tube body can be worn away by the abrasive action of sand or other abrasive particles in the producing fluid. It is often accelerated by aggressive corrosion pitting.

What to look for in Used Casing Inspection

The types of damage casing incurs while in service follow a predictable pattern. TUBOSCOPE inspection research has identified the major types of defects and has devised inspection techniques to locate and identify their severity.

Corrosion Pitting

Corrosion pitting is the most common defect found in used casing. The severity of the corrosion may vary with well conditions. The pitting may occur on either surface of the casing and may cover the entire length or exist only in isolated areas.

Mechanical Damage

Routine handling of the casing can frequently cause mechanical damage. This is particularly common in the slip areas where mashes can occur.