In April 2005, Overseas Shipholding Group (OSG) signed a $1bn bareboat charter deal with Kvaerner Philadelphia Shipyard (now Aker Philadelphia Shipyard) for the construction of ten Veteran-Class MT-46 product tankers. The number was later increased to 12. Construction of the tankers began in 2006. The first three were delivered in 2007, followed by eight in December 2009.
The delivery of the 12th vessel in April 2011 marked the conclusion of contract.
Some of the product tankers have already been leased to BP Shipping, Shell Oil and Tesoro. These product tankers will operate in the sea where there are no pipelines for transporting petroleum products.
In November 2007, Aker American Shipping signed a $1.3bn contract with its subsidiary Aker Philadelphia Shipyard for 13 more product tankers. These tankers are expected to be delivered to Aker American Shipping by 2015.
The product tankers have been built under the Jones Act. Passed in 1920, the act states that vessels used in the US have to be built and owned in the US. The act is meant to protect the US ship construction industry.
Veteran-Class MT-46 construction
Construction of the first product tanker began in October 2006. It was delivered to OSG in February 2007. The tanker Overseas Houston was leased to Shell Oil. The ship, operating in the Gulf of Mexico, carries neat petroleum products.
The Overseas Long Beach was delivered in June 2007. The ship is deployed with BP Shipping for transporting chemical and petroleum products.
The Overseas Los Angeles was delivered to OSG in November 2007. This was the second ship leased by OSG to BP Shipping. The ship is being used as oil and chemical carrier.
The Overseas New York was delivered in April 2008 and is used by Shell Oil.
The fifth vessel, Texas City, was delivered in September 2008. It is furnished with diesel-powered electrical generating sets and was also leased to BP Shipping.
The Overseas Boston was delivered in February 2009 and now operates for Tesoro, an oil and gasoline company.
The Overseas Nikiski was delivered in June 2009. The 600ft-long product tanker was the second ship leased to Tesoro for carrying petroleum products.
OSG took the delivery of Overseas Cascade in December 2009. The product tanker has been chartered to Petrobras America to transport crude oil from the US Gulf of Mexico.
The Overseas Martinez was launched in March 2010 and was delivered to American Shipping Company in May 2010. Construction of the 10th ship, Overseas Anacortes, began in February 2010 and it was delivered in September 2010. The ceremonial keel-laying for the 11th product tanker was held in March 2010.
The keel laying ceremony of the 12th vessel, Overseas Tampa, was held in August 2010. It was delivered in April 2011.
MT-46 tanker design
The ship is based on an Athenian-class 46,000dwt Jones Act product tanker. It has an overall length of 183m and moulded breadth of 32.2m. It can accommodate 32 people and has a cargo capacity of 330,000 barrels. At a 90% maximum continuous rating and 15% sea margin, the ship has a speed of 15kts.
Veteran Class propulsion
The ship is equipped with single screw propeller arrangement. A MAN B&W 6S50MC diesel engine with 11,640hp at 127rpm is being used to run the four-bladed fixed pitch propeller. Two sterntube bearings and one line shaft bearing holds a 14.5m-long propulsion shaftline. The undocking affect of shaft alignment is checked by measuring strain gauge alignment. Hydraulic steering gear has been provided by Rolls-Royce.