Flexible metal hose

A flexible metal hose for transporting a fluent substance,the hose formed from a metal strip generally helically wound about a hose axis, said metal strip having a generally “S” shaped cross sectional configuration formed by axially spaced radially inner and outer body portions and opposite strip edges formed by reversely curved radially outer and inner lips that extend from the respective body portions, the lips of adjacent convolutions intermitted to provide a first surface on one convolution that undergoes sliding movement relative to a second surface of an adjoining convolution when said hose is flexed;

• wherein the improvement comprises a plurality of projections and recessions on said first and second surfaces, said projections and recessions meshing to enable the surfaces to slide relative to each other generally parallel to the hose axis while substantially impeding relative sliding in directions not generally parallel to the hose axis, said first surface disposed on one convolution lip and said second surface formed on a body portion of the adjoining convolution, and a third smooth surface formed on the other convolution lip, said third surface biased into sealing engagement with a conforming sealing surface, the sealing engagement between said third and conforming sealing surfaces extending continuously along the hose on a generally helical path for blocking leakage of fluent material between said first and second surfaces.