Design, Manufacture, and Testing of Large Reduction Gears for Diesel Ship Propulsion Systems
The dramatic increase in both the size of ships and the power of propulsion systems over the past 15 years has led to a desire for shorter machinery spaces and lighter equipment in order to provide additional cargo carrying capacity. Many equipments and reduction gears in particular have experienced a growing number of problems due to compact designs with reduced scantlings. Consequently, high-horsepower and low-rpm gear units were developed that resulted in incompatibility of machinery and ship. Those marginal designs combined with manufacturing inaccuracies were in most cases the result of overzealous cost reduction programs. This paper presents some of the elements of a state-of-the-art reduction gear evolution cycle that will result in successful gear operation and continued long life.