Well, that's certainly what the EN means, though I'm only guessing for the FR term; but 'radoucir' is often encountered for things that are 'made less sharp' in this sort of way, which is what 'swept' means here. Otherwise, you might just describe it as being 'of generous radius'...

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Note added at 38 mins (2006-02-20 12:32:50 GMT)
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Well, a bit of Googling failed to reveal anything particularly helpful, except that they seem to refer to this soemtimes as a 'courbe 90°' --- the fact that it is a radiussed bend rather than a sharp L is really what is meant by the 'swept'

In terms of T-pieces, they seem to use 'pied de biche' for a 'running swept T', but clearly that is not applicable to a simple elbow!