Systems and methods for providing a sleeve reinforced subsea pressure vessel

Abstract

A subsea vessel includes an outer layer of non-corrosive material and an inner layer of high-strength material that both corroborate in a subsea environment to withstand external pressure and prevent corrosion. The subsea vessel further includes a cavity surrounded by the inner layer and outer layer for providing storage in and protection from the subsea environment. The cavity is accessible via an opening that extends through the inner layer and the outer layer. The opening can be opened and closed with a cooperating cap that impermeably seals the cavity. The cap may include a number or connection mechanisms for being selectively secured to the opening. In addition, the cap may include a portion formed of a high-strength material and a portion formed of a non-corrosive material.

What is claimed is: 
     
         1 ) A subsea vessel, comprising:
 at least one wall having an exterior surface and an interior surface;   the at least one wall forming an interior cavity defined by the interior surface, and the at least one wall further defining at least one opening for providing access to the interior cavity;   the at least one wall including an outer layer defining the exterior surface and an inner layer defining the interior surface, wherein the outer layer comprises a first material that is corrosion resistant and the inner layer comprises a second material that has a greater strength-to-weight ratio than that of the first material; and   a cap for sealing the at least one opening from a subsea environment when the subsea vessel is immersed in the subsea environment, the cap being removably attached to a portion of the at least one wall forming the at least one opening and including a surface that when in use abuts the inner layer for withstanding a load resulting from external pressure from the subsea environment.   
     
     
         2 ) The subsea vessel according to  claim 1 , wherein the cap is removably attached to the outer layer. 
     
     
         3 ) The subsea vessel according to  claim 1 , wherein the cap includes a flange that at least partially aligns with the outer layer when the surface abuts the inner layer. 
     
     
         4 ) The subsea vessel according to  claim 3 , further including at least one fastening member that removably connects the flange to the outer layer. 
     
     
         5 ) The subsea vessel according to  claim 3 , wherein the at least one opening has a circular-shape, and the cap includes at least one annular seal located between the flange and the surface that abuts the inner layer. 
     
     
         6 ) The subsea vessel according to  claim 5 , wherein the at least one wall defines a cylindrical shape extending axially between a first end and a second end, and the at least one opening includes a first opening on the first end and a second opening on the second end. 
     
     
         7 ) The subsea vessel according to  claim 6  further including a second cap for sealing the second opening, the second cap also being removably attached to the outer layer. 
     
     
         8 ) The subsea vessel according to  claim 1 , wherein the cap includes an exterior surface that at least partially comprises a corrosion resistant material, and the surface that when in use abuts the inner layer comprises a material that has a greater strength-to-weight ratio than that of the corrosion resistant material on the exterior surface of the cap. 
     
     
         9 ) The subsea vessel according to  claim 8 , wherein the corrosion resistant material on the exterior surface of the cap comprises the first material and the surface that when in use abuts the inner layer comprises the second material. 
     
     
         10 ) The subsea vessel according to  claim 1 , wherein the first material comprises at least one of a dielectric material, a plastic, or a metal and the second material comprises at least one of a metal, a metal alloy, or a ceramic. 
     
     
         11 ) The subsea vessel according to  claim 1 , wherein the first material comprises at least one of Titanium, polyvinyl chloride (PVC) or polyethylene (PE) and the second material comprises at least one of Aluminum, Titanium, Copper-Beryllium, High-Strength Steel, ceramic, or a Nickel Alloy. 
     
     
         12 ) The subsea vessel according to  claim 1 , wherein the at least one wall defines a spherical shape, a cylindrical shape, a rectangular shape, an oval shape, or an elliptical shape. 
     
     
         13 ) The subsea vessel according to  claim 1 , wherein the at least one opening defines threads comprised of the second material, and the cap defines threads for connecting with the threads in the at least one opening. 
     
     
         14 ) The subsea vessel according to  claim 7 , further including at least one fastening member that extends through the flange of the cap and a flange of the second cap, said at least one fastening member drawing the cap and the second cap towards one another to seal the subsea vessel. 
     
     
         15 ) A method of constructing a subsea vessel, comprising:
 forming an inner layer having an interior surface and an outer surface about an interior cavity defined by the interior surface;   forming at least one opening with the inner layer, the at least one opening providing access to the interior cavity and providing a bearing surface around the at least one opening, the bearing surface residing between the interior surface and the outer surface;   covering the outer surface of the inner layer with an outer layer, wherein the outer layer comprises a first material that is corrosion resistant and the inner layer comprises a second material that has a greater strength-to-weight ratio than that of the first material; and   providing a cap for sealing the at least one opening from a subsea environment when the subsea vessel is immersed in the subsea environment, the cap being removably attached to a portion of the subsea vessel and including a surface that when in use abuts the bearing surface for withstanding a load resulting from external pressure from the subsea environment.   
     
     
         16 ) The method of constructing a subsea vessel according to  claim 15 , wherein covering the outer surface of the inner layer with an outer layer includes molding the outer layer over the inner layer. 
     
     
         17 ) The method of constructing a subsea vessel according to  claim 15 , wherein covering the outer surface of the inner layer with an outer layer includes welding the outer layer to the inner layer. 
     
     
         18 ) The method of constructing a subsea vessel according to  claim 15 , wherein covering the outer surface of the inner layer with an outer layer includes coating the outer surface of the inner layer with the first material and allowing the first material to cure. 
     
     
         19 ) The method of constructing a subsea vessel according to  claim 15 , wherein the outer layer defines an outer cylinder extending between a first outer layer end and a second outer layer end, and the inner layer defines an inner cylinder extending between a first inner layer end and a second inner layer end, and wherein covering the outer surface of the inner layer with an outer layer includes inserting the inner cylinder into the outer cylinder. 
     
     
         20 ) The method of constructing a subsea vessel according to  claim 19 , wherein the outer layer has a first diameter between opposing interior surfaces thereof that is larger than a second diameter between opposing interior surfaces thereof, the first diameter being located near at least one of the ends of the outer layer, thereby facilitating guiding the insertion of the first inner layer end or the second inner layer end. 
     
     
         21 ) The method of constructing a subsea vessel according to  claim 19 , wherein the inner layer has a first diameter between opposing exterior surfaces thereof that is smaller than a second diameter between opposing exterior surfaces thereof, the first diameter being located near at least one of the ends of the inner layer, thereby facilitating guiding the insertion of the first inner layer end or the second inner layer end. 
     
     
         22 ) The method of constructing a subsea vessel according to  claim 19 , further including applying an adhesive between the inner cylinder and the outer cylinder and curing the adhesive. 
     
     
         23 ) The method of constructing a subsea vessel according to  claim 16 , wherein molding includes molding the outer layer which comprises at least one of Titanium, polyvinyl chloride (PVC), polyethylene (PE), dielectric material, or corrosion resistant material over the inner layer which comprises at least one of Aluminum, Titanium, Copper-Beryllium, High-Strength Steel, Ceramic, Nickel Alloy, or other metals and metal alloys.