Damage indicator for a composite pressure tank
A composite fuel tank, formed by winding filaments or strips around a plastic liner and binding the material with a curable binder. Embedded within the wrapped material at predetermined depths from the surface which provides a color indication of the level of damage due to tears, gashes, cuts and the like. The color indicator is part of a visual inspection method to determine tank damage and the extent of repair necessary.
1. A composite fuel tank for storing a pressurized fuel comprising:
a cylindrical tank ( 10 ) having a first hemispherical end, a second hemispherical end, and an external surface ( 19 );
an input/output end ( 20 ) disposed on the first hemispherical end;
wherein the cylindrical tank comprises: a liner ( 12 ); a first wrap zone ( 14 ) disposed around the liner; and
a second wrap zone ( 18 ) disposed around the first wrap zone;
wherein the second wrap zone comprises a first underzone ( 36 );
wherein the second wrap zone further comprises a second underzone ( 44 ) having a first color band ( 15 ) disposed therein;
wherein the first underzone is disposed nearer to the external surface of the tank than the second underzone; and
a second color band ( 85 ) disposed further from the external surface of the tank than the second wrap zone; and an intermediary wrap zone ( 87 ) disposed between the second wrap zone and the second color band;
wherein the second color band is of a color which contrasts with the wrap zone material in which it is disposed.
2. The tank of claim 1 wherein the first color band is of a color which contrasts with the second wrap zone.
3. The tank of claim 1 wherein the first wrap zone, second wrap zone, or both further comprises a wrapping material which is at least one of a filament or strip in at least one of a curable adhesive, epoxy and resin.
4. The tank of claim 3 wherein the filament or strips are at least one of weaves, braids or fabrics.
5. The tank of claim 3 wherein the filament or strips are at least one of mesh and netting.
6. The tank of claim 3 wherein the filament is coated and the coating when illuminated by wavelength of the correct size emits a color by the property of luminescence.
7. The tank of claim 6 wherein the coating is a chemical sensitive to UV light.
8. The tank of claim 1 wherein the first color band is positioned about 0.045 inches below the external surface ( 19 ) of the tank.
9. The tank of claim 1 wherein the first color band is positioned about 0.05 inches below the external surface ( 19 ) of the tank.
10. The tank of claim 1 wherein the second color band is positioned at a depth which corresponds to a pre-determined depth; and wherein that pre-determined depth is the depth of tank damage that requires the tank to be taken out of service.
11. The tank of claim 8 wherein the color band is a region of epoxy, resin or adhesive which contains a dye or pigment at the 0.045 depth.
12. The tank of claim 9 wherein the color band is a region of epoxy, resin or adhesive which contains a dye or pigment at the 0.05 depth.