Tool Technology
Unique Tool Design

The low temperature 1-11/16 inch diameter downhole tool assembly is rated to 10,000 psi, and 250°F permitting video logging operations into small tubulars and deep production. A hot hole camera is available for temperatures up to 400 °F for several hours. The light head is on the bottom of the tool string and houses the video camera in a pressure vessel. The camera sees through a clear optic view port. A 100-watt light source behind the camera illuminates the field of view allowing an unobstructed view in front of the camera. A polished reflector and quartz dome over the bulb serve to cast the light forward and to protect the bulb. This patented "back light" design allows for an unobstructed view of the wellbore that can be critical in a fishing job. Most other downhole video cameras place the bulb in front of the lens. This "front light" design obscures viewing in the center of the picture. Above the light head is a collapsible centralizer to center the camera in the well for better viewing and better distribution of light. Above the centralizer is the electronic chassis that launches the video signal along the cable to the surface. Above the chassis is the cable head connecting the tool string to the cable.

Lens Prep Technology
In the early days of video logging, cameras were only deployed with a rig on location because oil, if present even in the smallest quantity, would adhere to the lens and the rig was needed to continuously circulate clean water to keep oil off the lens. A patented, highly specialized lens surfactant, developed in the early 1990s, overcame this problem. The surfactant, when applied to the optic view port and lamp dome, repels oil, preventing it from adhering to the camera optic port that is in front of the video camera lens. The surfactant broadened the applications and success of downhole video so that oil in a well is rarely a problem when video logging. Through successful use of downhole video we learned oil and water quickly separate into their respective phases upon entering the well providing a good medium area throughout the producing interval. If a continuous phase of oil is encountered, the oil will obscure the view until the camera encounters another continuous phase of clear fluid. The lens surfactant is a milestone in downhole video logging, allowing operators to log idle wells containing a thick pad of oil without the need of a rig to displace the oil.

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