Method of determining if deterioration in structural integrity of a pressure vessel, a pressure vessel, and a structural integrity testing apparatus therefor

A structural integrity testing apparatus for a composite-reinforced pressure vessel having an exterior surface comprised of a composite material, comprising:

• (i) sensor means and oscillator means affixed to or embedded in said exterior surface;
• (ii) means for applying an electrical current to said oscillator means so as to cause said oscillator means to oscillate so as to produce a mechanical disturbance to said exterior surface and cause a detectable natural frequency response of said pressure vessel;
• (iii) means for recording said natural frequency response of said pressure vessel;
• and
• (iv) means for comparing said recorded resultant natural frequency response with a later-obtained natural frequency response, and determining if there be any difference therebetween.

A pressure vessel, comprising:

• an inner vessel;
• a reinforced material surrounding said inner vessel and forming an exterior surface;
• both sensor means and oscillator means affixed to or embedded in said exterior surface;
• and,
• means for storing a resultant natural frequency response as received from said sensor means, after a mechanical disturbance has been provided to said exterior surface of said pressure vessel by said oscillator means.