Intermediate Depth Logging Winch

The Intermediate Depth Logging Winch (IDLW) is a Mount Sopris logging hoist that has been modified for polar field use. The winch is capable of logging boreholes 1750 meters deep, can operate at temperatures as low as -45 degrees C, and is transportable by Twin Otter. The winch allows full-range speed control down to a complete stop, and can maintain a uniform logging speed as low as 2.5 cm/s. The winch includes a digital depth measuring system using a bi-directional counter with a precision of 1 cm or better, and a cable-tension measuring system and a motor cut-out in the event of over-tension. The winch allows for automatic re-spooling of the cable via a level-wind system. The cable is a Teflon-coated standard four-conductor logging cable headed with a standard 1-inch outer-diameter Gearhart-Owen variant. The winch has a broadband slip-ring connector enabling it to transmit both analog and high speed digital signals from DC to ~10 MHz. The winch has an aluminum ramp system for loading/unloading from a Twin Otter.

The IDLW has been used several times for logging the SPICEcore borehole at South Pole, and IDP engineers have implemented several user-recommended upgrades since those deployments. In 2023, a spare motor for the IDLW was purchased, received and wired.

A casing-mounted logging tower is available for use with the Deep Logging Winch.