CLYDE, Ohio — Twice unable to get satisfaction in its ongoing trade dispute with two South Korean washing machine manufacturers, Whirlpool Corp. is hoping the third try will stick.

The appliance maker wants the federal government to levy heavy tariffs on all washers sold in the United States that are made by either Samsung Electronics Co. or LG Electronics Inc.

Whirlpool, which claims the South Korean firms gained market share by illegally “dumping” washing machines on the U.S. market — that is, selling washers at well below the cost of production — is pressing its case via a seldom-used but otherwise powerful protectionist tool called a Section 201 safeguard petition.