Tanker Shipping

A principal function of the tanker sector is to transport crude oil from oil production and export facilities to oil terminals, storage facilities, pipeline systems and oil refineries internationally. In addition, tankers are also involved in the carriage of refined petroleum products, such as gasoline, diesel, jet fuel and naphtha, from refineries to storage and distribution systems, industrial plants and other consumers. Tankers generally are a more cost-effective alternative to pipelines and their advantages increase over distance. Pipelines are also considered to be more vulnerable to political instability, sabotage, economic blockade and the risk of environmental disaster.

There are two principal types of providers of international seaborne transportation services for crude oil and refined petroleum products: independent shipowners and end users, such as oil, energy, petrochemical and trading companies (both private and state-owned). Tonnage controlled by end users is primarily chartered from independent shipowners under short-term spot market contracts and long-term time charters, with the balance being directly owned. The prices for transporting crude oil and refined petroleum products, which are referred to as tanker charter rates, are set in highly competitive markets in which both independent and end-user tonnage participate.

In recent years, the tanker sector has undergone a process of consolidation that has resulted in greater cooperation between owners and charterers as both seek greater economic efficiencies and continued improvements in quality, safety and environmental protection standards. As a result, oil companies acting as charterers, terminal operators, shippers and receivers are becoming increasingly selective and rigorous in their inspection and vetting of vessels and their acceptance of vessels and operators. Safety and environmental protection has been a major focus of the tanker industry over the past years. Regulations such as OPA 90 and IMO have caused tanker owners to take extra care in the maintenance of their vessels. According to IMO regulation only double hull tankers will trade as of 2010 with single hull tankers phasing out.

Vessels in the tanker fleet can be divided into categories based on their size in deadweight tons, or dwt, which is a vessel's capacity for cargo, fuel, oil, stores and crew measured in metric tons (1,000 kilograms). The following are the main categories of tankers based on dwt:

1. Very Large Crude Carriers (VLCCs) -- tankers with capacity of 200,000 dwt and over.
2. Suezmax tankers -- tankers with capacity ranging from 120,000 to 200,000 dwt.
3. Aframax tankers -- tankers with capacity ranging from 80,000 to 120,000 dwt.
4. Panamax tankers -- tankers with capacity ranging from 60,000 to 80,000 dwt.
5. Medium Range tankers (MR) -- tankers with capacity ranging from 25,000 to 60,000 dwt.
6. Small tankers -- tankers with capacity up to 26,999 dwt. A 300,000 dwt tanker can carry 2 million barrels of crude oil, while a Suezmax can carry about 1 million barrels and an Aframax between up to about 800,000 barrels.

Tankers that transport refined petroleum products are referred to as products tankers. Products tankers generally range in size from 10,000 to 80,000 dwt, although there are some larger products tankers designed for niche long-haul trades, such as from the Middle East to Japan, Korea and South East Asia. Products tankers generally have cargo-handling systems that are designed to transport several different grades of refined petroleum products simultaneously. These systems include coated cargo tanks that facilitate cleaning between voyages involving different cargoes.

Ice Class tankers are vessels that have been constructed (in compliance with Finnish-Swedish Ice Class Rules) with strengthened hulls, a sufficient level of propulsive power for transit through ice-covered routes and specialized machinery and equipment for cold climates.