The United States says it will impose preliminary anti-dumping duties on large-diameter welded pipe from Canada and five other countries.
The U.S. Department of Commerce says it will collect 24.38 per cent cash deposits on imports from Canada that were worth almost US$180 million in 2017.
The other countries being hit with duties include China, Greece, India, Korea, and Turkey, with penalties ranging from 3.45 per cent for Turkey to over 132 per cent for China.
The U.S. department says it determined that exporters from those countries have sold pipe at less than fair value in the United States.
Final duty determinations are to be announced in early November for the China and India investigations and in January for Canada and the other three countries.
The department says enforcement of U.S. trade law is a primary focus of the Trump administration, noting it has initiated 120 new investigations since the president came to office, more than double the previous administration.