Seal for marine seismic source

Abstract

A marine seismic vibrator includes a housing having first and second housing portions defining an internal chamber therebetween. A hydraulic cylinder or other energizing device is connected between the first and second housing portions. The first and second housing portions are maintained in a spaced apart, non-contacting relationship. Relative motion between the first and second housing portions is provided by the hydraulic cylinder in order to generate acoustic waves in a surrounding body of water. An annular flexible seal construction is connected between the first and second housing portions for isolating the internal chamber from the surrounding body of water. This seal construction includes first and second flexible web portions sealingly connected to the first and second housing portions. A rigid hoop is connected between the first and second web portions for supporting the seal against pressure differentials between the internal chamber and the surrounding body of water. This hoop preferably has an axial length substantially greater than a radial thickness thereof. The first web portion of the seal extends from the first housing portion toward the second housing portion, then radially toward the rigid hoop, then away from the second housing portion, then again toward the rigid hoop, thus defining a serpentine cross section to accommodate relative motion between the first and second housing portions by bending deformation of said serpentine cross section.