Turkey's Borusan Mannesman to invest $150 million in U.S. factory ISTANBUL (Reuters) - Borusan Mannesmann (BRSAN.IS), Turkey's leading steel pipe manufacturer, will invest $150 million in building a production facility in the United States, the company said on Monday. The facility, which is seen starting operation in the second half of 2014, is expected to yield an annual revenue of $500-600 million depending on steel prices, the company said in a statement with the Istanbul Stock Exchange. Writing by Ece Toksabay; Editing by Helen Massy-Beresford