GE's Casing Collar Locator (CCL) responds to changes in metal volume, such as pipe collars and perforations.
As the tool passes a collar, or change in metal volume, lines of magnetic flux between two opposing permanent magnets are disturbed, causing a low frequency voltage or Electro Magnetic Field (EMF) to be induced in a coil mounted between the permanent magnets. Finally the signal is converted by a voltage-controlled oscillator for recording in the Ultrawire™ section of the tool.
- The CCL can be combined with other Ultrawire production logging tools
- Depth control in casing or tubing
- Location of casing or tubing damage
- Confirmation of perforation depths or intervals