Occurence: Incredible Hulk :Furture Imperfect #1

To help keep resistance down in an alternative future, the Maestro has created mechanical dogs called Dogs o' War whose jaws can crush adamtinum( the strongest metal in the Marvel Universe) in 7.3 seconds. The Hulk battles one and the dog gets the Hulk's head in it's jaws and is not even able to pierce the Hulk's skin before being defeated.

Hulk's Strength Feats

Incredible Feats of the Hulk Main Page