Jam weld

from The Collaborative International Dictionary of English v.0.48

Jam \Jam\, n. [Prob. fr. jam, v.; but cf. also Ar. jamad ice,
   jelly, j[=a]mid congealed, jamd congelation, ice.]
   A preserve of fruit boiled with sugar and water; also called
   {jelly}; as, raspberry jam; currant jam; grape jam.
   [1913 Webster]

   {Jam nut}. See {Check nut}, under {Check}.

   {Jam weld} (Forging), a butt weld. See under {Butt}.
      [1913 Webster]