TOWING OF LOGGING TOOLS

The installation of a blank liner has been used to tow logging tools into boreholes or other passages. Since the liner can be installed in any direction, vertically, horizontally, or other directions, the liner can be used to tow the tool into place instead of using the common push rod. The advantages over a push rod are the following:

1. The hole is stabilized by the liner reducing the hazard of rock fall.
2. No push rods need to be assembled from small sections
3. The labor of pushing the tool into the hole is eliminated
4. The liner interior fluid can be very compatible with the tools needs (e.g., sonic log in water filled hole)

The basic eversion process is found at Everting Liner Mechanism. Contact us for the procedure for towing a tool into the hole.

This technique has been used primarily for towing of neutron moisture sondes under landfills in passages built beneath the landfill containment system as the waste storage is constructed. However, the most attractive application is in the towing of small tools in holes drilled from a tunnel (e.g., ore body assessment). Tools can be towed for hundreds of feet in small (~2") horizontal holes, angle holes, and holes vertically upward.

An air lock system is used to pass the tool from the tunnel into the interior of the pressurized liner.

It is possible to tow a train of logging tools for a single pass logging of the hole.

For more information on this technique, contact us at