Konecranes makes AC breakthrough in US steel

KCI Konecranes of Finland has won a contract which it believes is a significant "breakthrough" in persuading US steel mills to adopt modern AC technology.

Konecranes America Inc. has won a contract to supply two hot metal cranes and a service crane to Nucor's steel mill in Jewett, Texas. Nucor is the largest steel producer in the USA.

This is Konecranes' first supply contract for a big US steel mill, and the first time that a US steelmaker has purchased hot metal cranes with AC technology, which Konecranes says offers significant operating savings over traditional DC solutions. The cranes will be delivered in April, July and August 2003.

Hot metal cranes represent the severest duty class and have to meet the most stringent safety standards of all industrial cranes. In a statement Konecranes said: "American steel mills have been somewhat reluctant to abandon old technical solutions, although new technology can offer significant savings in operating costs. KCI Konecranes possesses ample experience and knowledge in new crane technology, having delivered similar cranes to several steel mills around the world, including Scandinavia and the Far East." Nucor is building a new melt shop, with a new charge crane, ladle crane and a caster service crane. The charge crane is rated CMAA Class F at 200 US ton with two auxiliary hoists rated at 75 and 25 US ton. The ladle crane is basically the same configuration without the 25 ton auxiliary. The caster maintenance crane is rated at 100 US ton with a 35 ton auxiliary. All three feature AC drive systems with variable frequency controls.

Nucor maintenance supervisor Dick Rappolee said that the new facility was a one-furnace operation replacing three existing furnaces. "The furnace is twice as large as any of the three existing furnaces, and requires heavier crane equipment to service it," Rappolee said. "All of the technology is much more modern than what we previously had, including the AC induction motor cranes supplied by KCI Konecranes. As far as we know, induction AC-powered hot metal cranes of this capacity have not been seen in this country until now. We believe the operating costs will be lower due to increased reliability. As a break from a more traditional approach of redundant overhead cranes, we feel having the right crane in place eliminates the need for a second crane, which significantly reduces capital costs." A team from Nucor visited Konecranes' headquarters in Hyvinkää, Finland to meet with the crane designers and to see similar cranes in operation at AvestaPolarit's mill in Tornio, Finland and at SSAB in Lulea, Sweden.

Konecranes America's Houston manufacturing facility will build the cranes with input from Finland. KCI Crane Pro Services will undertake preventive maintenance.