Tank construction for liquified and/or compressed gas

Abstract

In a marine vessel for transporting or storing a cargo tank adapted to contain liquified and/or compressed gas which tank is mounted on supporting structure connected to the hull of the vessel, the tank has a peripheral integral interface structure such that the exterior periphery of the interface structure extends beyond the periphery of adjacent portions of the tank to define an extension member which is adapted to be rigidly secured to the tank support structure.

What is claimed is 
     
       1. In a cargo tank .Iadd.having at least one curvilinear peripheral surface and being .Iaddend.adapted to contain liquified gas .[.and which is.]. .Iadd., said tank being .Iaddend.mounted by a supporting structure extending tangentially to the tank in a marine vessel for transportation thereby or for storage, means for connecting said tank to said .[.support.]. .Iadd.supporting .Iaddend.structure, comprising.Iadd., .Iaddend.a one piece peripheral support member integral with and forming an annular portion of said tank .[.and.]. .Iadd.at said curvilinear peripheral surface, said support member .Iaddend.having .[.a.]. .Iadd.an inner surface which forms a portion of the inner surface of the tank and an extension .Iaddend.portion extending beyond said tank for operative connection with said .[.support.]. .Iadd.supporting .Iaddend.structure tangentially of the tank.Iadd.; said supporting structure comprising an integral skirt having opposed ends respectively rigidly secured to said extension portion of the support member and to the hull structure of the vessel; thereby eliminating the need for the secondary barrier normally used with LNG cargo tanks.Iaddend.. .[.2. Apparatus as in claim 1 wherein said cargo tank has at least one curvilinear peripheral surface and said 
     
     
        support member is located at said surface..]. 3. Apparatus as in claim .[.2.]. .Iadd.1 .Iaddend.wherein said cargo tank is a sphere .[., said supporting structure is an integral skirt secured to the hull structure of said vessel.]. and said support member comprises an annular ring .[., one 
     
     
        surface of which forms a portion of the wall of the tank.].. 4. Apparatus as in claim .[.2.]. .Iadd.1 .Iaddend.wherein said support member has a groove therein, said groove extending parallel to the adjacent periphery of said tank and defining .[.a.]. .Iadd.said .Iaddend.support member extension .[.adapted to be.]. .Iadd.portion rigidly .Iaddend.secured to 
     
     
        said .[.support.]. .Iadd.supporting .Iaddend.structure. 5.  Apparatus as in claim .[.2.]. .Iadd.1 .Iaddend.wherein said cargo tank is a sphere .[., said supporting structure is an integral skirt secured to the hull structure of said vessel.]. and said support member comprises an annular ring .[.having.]. .Iadd.including said extension portion, which extension portion is integral with said support member and comprises .Iaddend.an integral annular support extension substantially parallel to the adjacent peripheral surface of said tank, said .Iadd.annular support .Iaddend.extension providing a support surface for operative end abutting connection with .Iadd.one end of .Iaddend.said .[.support structure.]. .Iadd.skirt .Iaddend.and being positioned in a predetermined spaced location with respect to the remainder of said support member and said 
     
     
        tank whereby stresses in said tank are adapted to be predetermined. 6. Apparatus as in claim 5 wherein said tank is a pressure vessel of plate construction and said support member is an independent annular member 
     
     
        welded to said tank and forming a portion thereof. 7. Apparatus as in claim 6 wherein said support member is located at the equatorial plane of 
     
     
        said cargo tank. 8. Apparatus as in claim 5 wherein said extension is defined by an annular groove formed in said support member along a path 
     
     
        generally parallel to said tank. 9. Apparatus as in claim 8 wherein said groove has a generally semi-elliptical cross-sectional configuration, said 
     
     
        semi-elliptical groove opening away from said support member. 10. Apparatus as in claim 8 wherein said support member includes an 
     
     
        annular surface beveled towards said tank. 11. In a cargo tank having at least one horizontal circular dimension and adapted to contain liquified gas, which tank is mounted by a supporting structure, extending tangentially of said tank, on a marine vessel having refrigeration means associated therewith for maintaining said gas in its liquid phase, means for connecting said tank to said support structure, comprising a one piece horizontal annular section of said tank having an exterior dimension and section which defines an extension located in tangential relation to said tank for operative end abutting connection to said .[.support member.]. .Iadd.supporting structure; said supporting structure comprising an integral skirt having first and second opposed ends, with said first end thereof rigidly connected to said extension and said second end rigidly connected to the hull structure of the vessel; thereby eliminating the need for the secondary barrier normally used with LNG cargo 
     
     
        tanks.Iaddend.. 12. Apparatus as in claim 11 wherein said horizontal annular section comprises an annular ring welded to the remainder of said 
     
     
        cargo tank. 13. Apparatus as in claim 12 wherein said ring includes an annular groove adjacent the periphery of said tank, said groove defining 
     
     
        said extension. 14. Apparatus as in claim 13 wherein said groove has a semi-elliptical configuration, and said configuration opens away from said 
     
     
        ring. 15. In a cargo tank adapted to contain liquified gas and which is mounted by a supporting structure, extending tangentially of said tank, on a marine vessel for transportation thereby, .Iadd.or for storage, .Iaddend.means for connecting said tank to said support structure comprising a one-piece peripheral support member integral with and forming a portion of said tank, said support member having a greater width than adjacent sections of said tank whereby a portion of said support member extends beyond and in tangential relation to said tank for operative end abutting connection with said .[.support.]. .Iadd.supporting .Iaddend.structure .Iadd.; said supporting structure comprising an integral skirt having first and second opposed ends, with said first end thereof rigidly connected to said extension and said second end rigidly 
     
     
        connected to the hull structure of the vessel.Iaddend.. 16. In a cargo tank having at least one horizontal circular dimension and adapted to contain liquified gas, which tank is mounted by a supporting structure, extending tangentially of said tank, on a marine vessel having refrigeration means associated therewith for maintaining said gas .[.at.]. .Iadd.in .Iaddend.its liquid phase, means for connecting said tank to said .[.support.]. .Iadd.supporting .Iaddend.structure comprising a one piece horizontal annular section of said tank having an interior dimension substantially equal to the interior dimensions of adjacent portions of said tank and having an exterior dimension greater than the exterior dimensions of adjacent portions of said tank whereby said tank section defines an extension located in tangential relation to said tank for operative end abutting connection to said support member. .Iadd. 17. In a marine vessel for transporting or storing liquified gas and having a hull structure, a spherical tank adapted to contain liquified gas, an annular skirt tank supporting structure having upper and lower edges and a diameter slightly larger than the diameter of said tank, said lower edge of the skirt being rigidly secured to the hull of said vessel; said tank including a one piece horizontal annular section for connecting the tank to the upper edge of said skirt, said annular section having an interior dimension substantially equal to the interior dimensions of adjacent portions of the tank to define a substantially smooth uninterrupted inner surface in the tank and also having an exterior dimension which is greater than the exterior dimensions of adjacent portions of the tank, whereby a portion of said annular section extends beyond the exterior of adjacent portions of the tank, said annular section also having an annular downwardly opening groove formed therein located exteriorly of the tank to define an exterior extension portion of the annular section located in tangential relation to the tank, said exterior extension portion being rigidly connected in end abutting relation to said upper end of the annular skirt tank supporting structure, whereby said tank is supported by said skirt on the hull of the vessel through rigid connections and the stresses to which the tank and annular section will be subjected can be predetermined. .Iaddend..Iadd. 18. In a tank for liquified gas having at least one horizontal curvilinear dimension and being adapted to contain liquefied gas, which tank is mounted by a supporting structure extending tangentially of said tank on a marine vessel for transportation or for storage thereby, means for connecting said tank to said supporting structure comprising a one piece peripheral support member integral with and forming a portion of said tank, said support member having an inner surface forming a portion of the inner surface of the tank and forming a continuous extension of adjacent portions of the tank, said adjacent portions of the tank on opposite sides of said support member being in alignment with each other to define a substantially smooth inner surface in the tank at the support member; said support member having an outer surface and a width dimension between said inner and outer surfaces that is greater than the width dimension of adjacent sections of the tank whereby said support member defines a support extension portion located outwardly of any adjacent portion of the tank and in tangential relation thereto for operative end abutting connection with said supporting structure, said support member also having an annular semi-elliptical groove formed therein adjacent the periphery of said tank, opening away from the support member and towards the supporting structure. .Iaddend.