Chicago Bridge & Iron ( CBI) was the only new position Berkshire Hathaway initiated last quarter, and it's another conviction buy this quarter. Berkshire increased its holdings of CBI by 3.04 million shares -- or 46%. That gives Buffet & Co. nearly 10% of CBI's outstanding shares at last count. >>5 Earnings Stocks Everyone Hates -- but You Should Love CBI is a worldwide engineering and construction firm. The firm's specialty comes in constructing energy facilities around the globe, but it's got a particular niche in building facilities that handle liquefied natural gas. Around 20% of CB&I's sales come from building steel plate structures that industrial customers use to store material. In recent years, CB&I has begun reaching away from its core construction and engineering business, adding on new ways to service its existing petrochemical customers. The Lummus Technology unit, for instance, sells gas processing and refining technology. While it's still a small chunk of CBI's revenues, it's a lucrative one. Nuclear is another important stronghold for CBI. The acquisition of the Shaw Group made the firm one of the biggest manufacturers of nuclear energy facilities, which carry huge upfront construction costs in exchange for extremely low operating costs. That's an attractive tradeoff when corporate balance sheets are stuffed but uncertainty remains high. CBI may not be the most exciting name on the list from a consumer standpoint, but its recent buying spree has transformational implications for the firm's income statement.