Upgrades to Minnesota’s historic Byllesby Dam are expected to double the dam’s power generation capacity to 4.4 megawatts, and a crane from Dawes Rigging & Crane Rental, a member of the ALL Family of Companies, was trusted with the critical role of placing the two new generators.
Dawes specified a Manitowoc MLC300 Lattice Boom Crawler Crane with VPC-MAX® for the job. This Variable Position Counterweight actively engages all counterweight and eliminates the need for passive carbody weights, resulting in a dramatically reduced transport configuration and better center of gravity for reduced ground bearing pressures and added capacity. The VPC-MAX attachment provides capacities similar to wagon- or tray-mounted attachments, but requires significantly fewer components and assembly steps, which reduces setup time and transportation costs.
Terry Hoops, Regional Sales Representative for Dawes, stated these features were critical to setting the 110,000-pound generators. “This was an extremely tight job site,” said Hoops. “Between the dam, the Cannon River, and other buildings on the site, our laydown area was roughly a half-mile away from where we actually had to build the crane.”
As a result, the fact that Dawes only needed 11 truckloads to deliver the MLC300 was a plus. “With fewer truckloads, we needed less space for the staging area. That’s less cost for the customer, a smaller footprint, and quicker assembly,” said Hoops. “After delivering the loads to the laydown area, we trucked components to the build site one at a time – first bringing over the tracks, carbody, counterweights and then the boom sections.” Dawes also brought a 100-ton Tadano GR-1000XL Rough Terrain Crane to assist with assembly of the MLC300.
Other, similar-sized crawlers cranes would have required up to three times as many loads, increasing delivery fees and set-up time, and had a larger footprint requiring additional ground matting. An all-terrain crane that could handle the weight of the job at the prescribed radius would have needed at least double the capacity.
Configured with 216 feet of main boom and 474,000 pounds of counterweight, The MLC300 offered the right combination of smaller footprint and large capacity to pick and set the two generators. The process took several hours for each generator, as on-site engineers supervised the securing of the generator connections. After completing the lifts, remaining connections were finalized.
Community leaders in Cannon Falls, Minnesota, tout the project as the first in the nation to generate more electricity through renewable resources than will be needed by the local community. It enables the dam to produce clean power more efficiently and more reliably, with excess electricity expected to be sold to help offset the project’s cost. The job was a joint effort of Dakota County, The Boldt Company, and Xcel Energy.