Bring in the Bots

Refueling Outages Use Robots for Specific Tasks

If SUSI had an online dating profile, it would most likely read, “Likes to swim. Loves to travel. Very flexible. One of a kind.”

Peak your interest?

The submarine robot SUSI swims in the spent fuel pool during Oconee Nuclear Station's recent refueling outage.
The submarine robot SUSI swims in the used fuel pool during Oconee Nuclear Station’s recent refueling outage.

Well, despite SUSI’s curious tagline, she’s hardly got time to create a dating profile. In fact, if she’s not resting, she’s most likely jet-setting around the world or diving through radioactive water.

SUSI, which stands for SU(bmarine) S(ystem) (for) I(nspection), is a one-of-a-kind submarine robot, provided by the German subsidiary of AREVA, that travels around the world assisting nuclear plants during refueling outages and in-service inspections – she is the most flexible submarine tool in the nuclear industry thanks to her wide range of applications for under-water component handling.

Most recently, she assisted Duke Energy’s Oconee Nuclear Station during its unit 3 refueling outage. At Oconee, SUSI provides visual inspections of primary components, such as the reactor vessel, pressurizer, steam generator and main coolant lines.

She is also used for foreign object search and retrieval (FOSAR) when things are found where they shouldn’t be.  SUSI is one of many unique robots that aid nuclear plants during refueling and maintenance outages and in-service inspections – Duke Energy uses a diverse fleet of robots for a wide range of jobs.

For instance, the 510 PackBot, used at Robinson Nuclear Plant, is a tracked system with a manipulator arm that can accurately manipulate objects as small as a watch battery – its arm can reach up to seven feet. Equipped with a thermal camera, the 50-pound robot can enter areas where it may be unsafe to send plant personnel, such as inside the containment building during plant operations. Personnel at Robinson Nuclear Plant and McGuire Nuclear Station have used the 710 Warrior robot during outages, as well. The Warrior is a rugged robot capable of carrying up to 200 pounds, and is primarily used to handle radioactive materials, such as filters used to clean water in the reactor vessel.

While these robots can do it all (i.e., swim, lift, crawl – and best of all, they don’t talk back!), robots are especially beneficial in radiological areas to reduce and/or completely eliminate the radiological dose workers receive during specific tasks.

Before bots, personnel handled these specific tasks in specialized protective clothing using poles to manipulate objects. While the manual process is still used when robots aren’t available, it presents a variety of challenges, such as the potential for human error and increased radiological dose. While receiving radiological dose is an expected part of the job for workers trained to work in certain areas, nuclear safety drives the industry to ensure workers receive as little radiological dose as possible.

The 710 Warrior is one of many robots that can take care of specific tasks during nuclear refueling outages.
The 710 Warrior is one of many robots that can take care of specific tasks during nuclear refueling outages.

Technology has made it possible for robots to not only help reduce radiological risk among workers, but they also improve work processes and job efficiency, which directly impact cost savings. When time is critical and the job is risky, robots lend helpful hands in getting the job done.