Patent ID: 8523245

Claim:
A tube fitting, having a longitudinal axis, comprising: a first fitting component comprising a ferrule camming surface, a second fitting component comprising a socket with a ferrule drive surface and a tapered wall that tapers at an angle ε relative to the longitudinal axis, a front ferrule and a back ferrule, said back ferrule engaging said ferrule drive surface and a rearward portion of said front ferrule when the fitting is in a finger tight position, said front ferrule comprising a tapered outer surface that engages said ferrule camming surface when the fitting is in a finger tight position, said tapered outer surface of said front ferrule extending radially outwardly from a forward portion of said front ferrule towards said rearward portion of said front ferrule, said rearward portion of said front ferrule comprising a radially extending flange portion and an outer wall portion that tapers radially inwardly at an angle μ relative to the longitudinal axis from a forward end of said radially extending flange poration towards a back end of said front ferrule, said angles ε and μ have the relationship ε≠μ when the fitting is in a finger tight position.