The company told TradeWinds deliveries will begin in 2015.
It has not yet decided how to employ the latest 12 63,800-dwt vessels, saying the terms of any charters were dependent on the market.
But the company is confident that the time is right to expand.
It ordered eight ships last year for $24.9m each. The next four are costing the same, with the final eight priced at $25.2m
