Yes, welt is a Scrabble word!
...and is worth 7 points in Scrabble, and 8 points in Words with Friends
welt
Verb
1. Beat severely with a whip or rod
2. Put a welt on
Noun
1. A raised mark on the skin (as produced by the blow of a whip); characteristic of many allergic reactions
2. A raised or strengthened seam
What Scrabble words can I make with the letters in welt?
3 Letter Words
2 Letter Words