Bermuda-based Ingersoll-Rand Company Ltd. has agreed to sell its Dresser-Rand business unit to the U.S. investment company First Reserve Corporation for a cash price of 1.2 billion U.S. dollars, the two companies announced Thursday. Dresser-Rand produces compressors, turbines, and control systems for the oil and natural-gas industry. The company, which operates worldwide with about 4,500 employees, recorded a turnover of 447 million dollars and operating profits of 25.2 million dollars. Ingersoll-Rand CEO Herbert L. Henkel said it intended to focus on its core business areas of climate control, industrial products, and security systems. First Reserve is specialized on takeovers of companies in the energy sector.