Gruvön Gruvön, Sweden Home of the world’s strongest fluting, Billerud Flute® and a pioneer in several areas including the development of BillerudKorsnäs FibreForm®. Production capacity: 685 000 tonnes/year. Number of employees: 880 (approx). Products: Kraft paper, sack paper, corrugated solutions.(fluting, liner), liquid board, cup stock, market pulp.