The U.S. Commerce Department will decide whether to launch an investigation into charges that South Korea and eight other countries are selling about $1.8 billion of steel pipe in the United States at unfairly low prices, the department said. A group of U.S. producers - including U.S. Steel, Maverick Tube Corporation and Energex Tube - filed a petition this month asking for duties on oil country tubular goods from the nine countries. The pipe is used in oil and natural gas production. A 20-day period for the Commerce Department to consider the petition expires this week. While it could be rejected, attorneys rarely file a petition unless they are certain that it meets the minimum legal threshold for a probe to be started. Meanwhile, the U.S. International Trade Commission will hold a preliminary conference on Tuesday to hear arguments from companies on both sides of the case. That would set the stage for the panel to vote by mid-August on whether there is enough evidence that the imports are injuring U.S. producers for the case to proceed. The United States imported nearly $1.8 billion worth of pipe from the nine countries in 2012, including $831 million from India, $217 million from India and $189 million from Vietnam, the Commerce Department said. Other countries named in the case are the Philippines, Saudi Arabia, Taiwan, Thailand, Turkey and Ukraine. Under the U.S. system, the Commerce Department investigates charges of unfair trade and determines what level of duties are appropriate. However, the ITC has the final word on whether duties are imposed. (Reuters)