roller ironer vs flatwork ironer

roller ironer and flatwork ironer both are nouns.

Word	Noun	Adjective	Verb	Adverb
roller ironer	Yes	No	No	No
flatwork ironer	Yes	No	No	No

As nouns, roller ironer and flatwork ironer are synonyms defined as:

roller ironer and flatwork ironer: a machine with a large, heated roller that irons and dries sheets, table linens, pillow cases etc.

roller ironer (noun)	flatwork ironer (noun)
a machine with a large, heated roller that irons and dries sheets, table linens, pillow cases etc.	a machine with a large, heated roller that irons and dries sheets, table linens, pillow cases etc.