HIGH STRENGTH FLEXIBLE FERRULE

摘要

A ferrule (120) for coupling a tube (112) to a fitting body (114) includes an outer cam surface (124) for bearing against the fitting body or another ferrule; an inner surface (126) defining a central bore (128) extending through a length of a body of the ferrule along a longitudinal direction from a bite edge (138) to a nut end (129); a recess surface (134) defining a counter bore extending from a bite end (137) to the bite edge (138), the bite edge (138) thereby recessed from the bite end (137).

主权项

1. A ferrule for coupling a tube to a fitting body, the ferrule comprising:
a nose portion including an outer cam surface for bearing against a fitting body or another ferrule to bend radially inward during assembly of the ferrule; an inner surface defining a central bore extending through a length of a body of the ferrule along a longitudinal direction from a bite edge to a nut end; a recess surface defining a counter bore extending from a bite end to the bite edge, the bite edge thereby recessed from the bite end a distance, X, along the longitudinal direction toward the nut end; and a first thin section toward the bite end; wherein an axially middle portion, between the first thin section and the nut end, is configured to bow radially outwardly during assembly of the ferrule such that the bite edge and a portion of the inner surface opposite the bite edge, relative to the axially middle portion, are engageable with the tube; wherein a radial distance, A, from the recess surface to the outer cam surface at an axial location of the bite edge is 50% or greater than a radial distance, H, from the inner surface to the recess surface; wherein the ferrule includes a nose angle, θ, defined by the longitudinal axis and the outer cam surface, the fitting body or the another ferrule includes a body seat angle defined by the longitudinal axis and a radially inwardly facing surface of the fitting body or the another ferrule, and the nose angle, θ, approximately matches the body seat angle of the fitting body or the another ferrule both before and after the nose bends radially inward during assembly of the ferrule, thereby reducing bending stress across a nose thickness, T, during makeup of the ferrule; wherein the nose thickness, T, extends normal to a portion of the outer cam surface to an axial end, of the recess surface, that is opposite the bite end; and wherein the entire portion of the outer cam surface is engageable with the radially inwardly facing surface of the fitting body or the another ferrule both before and after assembly of the ferrule.