Abstract: A flow straightener device for a turbomachine including an inner shell ring and an outer shell ring surrounding the inner shell ring, at least one out of the inner shell ring and outer shell ring having first orifices; at least two flow straightener vanes each including, at least at one same first end, an attachment platform having second orifices positioned facing the first orifices; the at least two vanes being assembled with at least one of the inner shell ring and outer shell ring by at least one first device of attachment introduced into the first orifices and the second orifices. The flow straightener device includes a covering platform covering the at least one first device of attachment.