The Collaborative International Dictionary of English v.0.48:

Welt \Welt\, v. t. [imp. & p. p. Welted; p. pr. & vb. n.
   Welting.]
   To furnish with a welt; to sew or fasten a welt on; as, to
   welt a boot or a shoe; to welt a sleeve.
   [1913 Webster]