In-House Repairs Keep High Priority Oak Ridge Project on Track

Isotek employees use manipulators to handle nuclear material and perform tasks to process and downblend uranium-233 inside protective hot cell structures.

OAK RIDGE, Tenn. - Oak Ridge Office of Environmental Management contractor Isotek recently took a different approach to machinery installation and repairs, saving time and money on the highest priority cleanup project at Oak Ridge National Laboratory (ORNL).

Isotek is responsible for eliminating the inventory of uranium (U)-233 stored in the world's oldest operating nuclear facility, located at ORNL. That material presents risks and is costly to keep safe and secure. Originally created in the 1950s and 1960s for potential use in reactors, U-233 proved to be an unviable fuel source.

Half of the U-233 inventory was disposed of between 2011 and 2017. The remaining material requires processing to convert it into a form safe for shipment and disposal.

That processing requires highly skilled and trained employees who operate manipulators. The machines are essentially the "hands" that handle nuclear material, performing tasks inside protective hot cell structures.

While manipulators can perform intricate tasks and lift as much as 100 pounds, they are delicate machines with lots of small parts and cables that require absolute precision timing to work properly.

Small issues with manipulators can result in major impacts to the project.

During the first eight months using the manipulators, beginning in 2022, Isotek experienced excessive downtime due to malfunction issues. Each time, manipulator repairs caused processing delays as the project waited for subcontracted technicians to arrive.

And once the subcontracted support arrived, repairs were difficult to perform due to employees' lack of experience on the state-of-the-art manipulators.

Isotek brought in a technical expert for two weeks to train millwrights on how to maintain and repair manipulators essential to the Uranium-233 Disposition Project.

Isotek primarily uses a brand of manipulators fabricated in Germany. With no local subject matter experts, Isotek brought in a technical expert from Germany to help train the contractor's in-house millwrights.

Over the course of two weeks, the expert trained them on the proper way to repair, assemble and install the manipulators. Isotek recorded the training for use in instructing future millwrights.

"I am amazed at how quickly our millwrights and other maintenance staff learned this new skillset and have employed it to help the project meet schedule," said Sarah Schaefer, Isotek president and project manager. "They are masters of their craft."

Having the training and expertise in-house allows for much faster repairs and avoids delays caused by limited availability of other repair technicians. That helps the project remain on schedule with processing operations.

Among the topics covered in the two-week training on maintaining and repairing manipulators were the proper methods to install the machines into the hot cell structures. Repairs often require the machinery to be removed.

Isotek has already exceeded its 2024 performance goals for processing U-233, six months ahead of schedule.

The contractor has more than 10 manipulators in use on the U-233 Disposition Project. In addition to the training, Isotek repurposed space for the millwrights to conduct maintenance and repairs.

Since making those adjustments, the hot cells have not been shut down for unplanned manipulator repairs. Repairs only take half a day.

"The establishment of the manipulator repair space and training has allowed Isotek operations to meet schedule and focus on the day-to-day challenges of processing U-233," said Schaefer. "The manipulator is no longer the concern."

-Contributor: John Gray