Wireline Removal:

When a string containing a wireline is to be stored for any period of time, it is appropriate to remove the wireline, inspect it, and protect both the string and the wireline. QT has developed special methods for wireline removal. At customer request, wireline may be inspected for continuity and shorts.

Wireline Insertion:

QT will insert a wireline into a string and check the continuity of each strand. Wireline is generally inserted by the fluid-pumping method (Figure 3), in which the line is fed into the tubing via a fast-flowing fluid. Inclusion of an electric cable inside a coiled tubing string has advanced the development of a new generation of applications. This has allowed many procedures previously performed by electric line to be coupled with the capabilities of coiled tubing, such as:

• Extended reach well access
• Production and open hole logging
• Well perforating
• Circulating while logging
• Downhole video camera
• Well treatment

For wireline operations, the installed cable is currently standard cable. Most logging service applications require only a mono-cable, but many other wireline operations, such as formation evaluation logs, formation micro-scanners and video cameras, require the use of multi-conductor and coaxial cables.

Sufficient "slack" must be allowed to prevent cables from coming under tension during downhole operations. Wireline inspections verify both electrical continuity and insulation integrity.