Casing Collar Locator

Description

Casing Collar Locator

Technical Description

The Casing Collar Locator (CCL) is an essential correlation tool used in cased-hole wireline operations. In the context of perforation, it acts as the primary “eyes” of the operator, providing the data necessary to match the depth of the perforating guns with the specific geological zones identified in previous logs. All our CCL are rated 200 C or 400 F. The pressure rating is minimum 15,000 psi, depending on the model the CCL length varies between 13″ and 15″.

• Magnetic Sensing Principle: The CCL contains a set of permanent magnets and a central coil. As the tool passes a casing collar (where there is a significant change in metal mass), the magnetic field is disturbed, inducing a small voltage spike in the coil.

• Depth Correlation: This signal is transmitted up the wireline to the surface, appearing as a “kick” on the log. By comparing these kicks to a baseline “Completion Log,” the operator can determine the exact position of the tool string within the wellbore.

• Ruggedized for Ballistics: Unlike standard logging CCLs, the Perforating CCL is specially engineered to withstand the extreme shock and high-frequency vibrations generated by the detonation of shaped charges in the perforating gun string.

• Dual-Functionality: Many modern CCLs are designed as “Pass-Thru” units, allowing electrical firing signals to pass through the CCL to the detonator below while simultaneously transmitting depth data to the surface.

• High-Temperature/High-Pressure (HTHP): Built with specialized internal electronics and high-grade housing, these tools are rated for the intense temperatures and pressures found in deep-well environments.