Spent Fuel Ginna Nuclear Plant

Constellation Energy, as a major generator of electricity, with a diversified fleet of nuclear facilities located throughout the United States, selected Wheelift's integrated solution for movement of horizontal fuel casks within their NUHOMS® Independent Spent Fuel Storage Installation (ISFSI).

*NUHOMS® is the registered trademark of Transnuclear, Inc.

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Horizontal storage modules

For nuclear plants that are planning new or expanded ISFSIs that are using or intend to use the NUHOMS® system for spent fuel storage, Doerfer's self-propelled transporter technology dramatically simplifies and shortens the campaign work process of spent fuel moves both in fuel loading and at the ISFSI site. These all-directional transporters effortlessly maneuver in much smaller spaces allowing the horizontal storage modules (HSM) to be much closer together. The wide alleys that are necessary today for maneuvering trailer-mounted transfer cask skids can be made much narrower in new facilities and expansions in existing facilities to gain additional storage locations. In this case, when the cask transporter approaches an alley that runs between storage modules, rather than turn into the alley the transporter can simply stop and rotate its axles 90° and drive sideways down the alley — with only a foot or so of clearance, if desired.

"Magical" is the term heard repeatedly during the fuel move campaigns. Extreme motion control flexibility and move precision drove productivity, significant safety improvements in dose reductions, labor savings, along with eliminated redundant ISFSI pad clutter.

Where precision position adjustments are required like changing from Normal linear forward travel mode to Lateral or Rotate for alignment adjustments, the transporter remains stationary as the axles sequentially rotate to the new mode. With whatever sideways or angular adjustment confirmed, all of the axles can either hold at that position or return to the prior mode for further fine adjustment. The operator has precise fingertip control for adjusting pitch, roll, and yaw to reach the exact vertical and horizontal insertion plane alignment. Adjustments within thousandths of an inch are routine.

The cask transfer coupler, or grapple, uses Wheelift's innovative electromechanically operated grapple fingers in lieu of the industry's standard hydraulic offering, eliminating all possibilities of hydraulic oil leak contamination in event of a line rupture.

With the insertion completed, the ram withdraws and the transporter backs away to go to its next mission. The insertion ram design is also a Wheelift innovation. The ram has a powered vertical adjustment for effortless droop deflection control, along with a quick release grapple assembly that is easily removed to provide clearance during cask down loading in the fuel building.

A critical requirement was to have the ability to travel over the existing asphalt roadway up to the ISFSI. Doerfer's load sharing Wheelift technology is the enabler for this need.

CHALLENGE: Provide a common integrated system to CE's (Constellation Energy's) Ginna nuclear plant in upstate New York, for the handling, transportation, and loading of spent fuel transport casks into NUHOMS® Horizontal Storage Modules (HSM) at Ginna and two other existing ISFSI locations. An alternative was needed for the problematic Greiner trailer system.

SOLUTION: Wheelift designed an autonomously operating self-propelled transporter providing maneuverability and significantly expanded operating capabilities at all points through the operations.

The final design, consisted of a weatherized diesel powered omni directional traveling transporter with four more axles than would normally be required, all with oversize wheels. Although the transporter could have been rated for a capacity of 215 tons, it was derated to 135 tons to accommodate travel on the asphalt roads leading to the ISFSIs at some sites. These transporters have infinitely variable travel speed 0 to 110 FPM, 10" vertical lift — used both for self-loading of the cask skid as well as compliance to uneven road conditions during travel.

BENEFIT:

• Data showed that total dose f(gamma + neutron) or the DSC (Dry Shielded Canister) transfer during the four fuel moves from the 2010 ISFSI campaign at Ginna was consistently less than one-tenth the total dose for the single most efficient DSC transfer during campaigns in the same period at a sister site using the conventional Transnuclear® Greiner trailer equipment.
• Allowed ISFSI pad to be designed comfortably with 36' access aisles vs. the norm of 60' aisles
• The ability to precision maneuver in any direction in the X, Y, and Z planes simplifies cask alignment and shortened work schedules, driving campaign labor cost reductions
• Maximum tire surface contact pressures of less than 425 psi tire allows travel over existing asphalt roadways
• Provides significant reliability improvements over all traditional industry standard processes
• Provides enhanced security through tight process control and reduced clutter
• Provides year-round transporter usage flexibility for additional heavy load move requirements

On-Center rotation

The on-center rotation axles have interconnecting fluid lines that divide them into load sharing groups to assure that every wheel carries only its specific share of the load, regardless of slopes and irregularities in the road surfaces.

At the Ginna nuclear plant, Constellation Energy has proven the multi-function capability of these Wheelift transporters. The Ginna plant regularly uses their transporter for heavy haul and heavy rigging applications within the plant, such as the installation of reactor core cooling pumps.

Wheelift Transporters and AGVs are manufactured in central Iowa and are custom engineered to application specific requirements. Chassis and fixtures are available with load capacities to 500+ tons and deck heights as low as 18.5". Power options include diesel, LP gas, battery, and umbilical cord. Computerized all electric omni-directional drives are standard with individual axle ratings of 15, 20, or 30-ton.

Wheelift® is a Doerfer Companies technology. Doerfer engineers and builds application specific manufacturing machinery and systems. Operating from four North American locations with over 700,000 sq. ft. and 500+ employees, Doerfer offers an array of engineering and manufacturing resources and is NQA-1 certified.

SUMMATION: ISFSIs based on the NUHOMS-type horizontal storage systems have taken on a whole new range of capabilities for efficient spent fuel handling based on the flexibility that Wheelift transporters and skids provide.

Click on image below to hear what the Ginna Nuclear Plant people have to say about this new capability.

TRADEMARKS

The following terms that are used through this website: Wheelift^®, Uniload^®, SynchroSteer^®, StackAxle^®, TrackAxle™ and OmniAxle^™ are all trademarks that are exclusively licensed to Doerfer Companies.