Nucor ( NUE) said its first-quarter earnings will be stronger than expected, thanks to robust steel shipments and high margins. Nucor expects to earn $2.20 to $2.40 a share in the quarter, up from its previous guidance of $1.90 to $2.10 a share. The Thomson First Call consensus for the three months ending in March was for earnings of $2.10 a share. "Nucor's margins in the first quarter have been favorably impacted by a stable scrap pricing environment," the company said. "Nucor continues to benefit from product line diversification, and all product lines have exceeded performance expectations for the first quarter. "We anticipate that the second quarter of 2006 will continue to be strong as overall demand and, in particular, the non-residential construction markets continue to improve," Nucor said. "The results for the second half of the year will depend on the level and pricing of imports, which could negatively influence the balance of supply and demand in the market." Analysts expect Nucor to earn $1.95 a share in the second quarter and $7.59 a share in the full year. The stock rose $2.73, or 3%, to $92.83 in premarket trading. In sympathy, U.S. Steel ( X) rose 2.5% and Oregon Steel ( OS) rose 1%.