Suspended deck for liquid natural gas tank

Abstract

A non-welded deck used to support insulation from the roof of a low temperature or cryogenic storage tank is disclosed. The deck may be comprised of a plurality of spaced apart bars with metal sheets covering the spaces between the bars. The edge of the metal sheets may be clamped to the bars to form the deck. The edges of adjacent metal sheets may overlap and be clamped together in such a way as to deform the sheets creating a metal-to-metal vapor and dust proof seal. The plurality of clamping bars and support bars may secure the metal sheets with sufficient strength to allow the entire deck to support loadings as a stressed membrane. The tank may be constructed with hardware that remains secure even after being subjected to repeated thermal cycling of over 200° Celsius (360° Fahrenheit).

1 . A insulation deck for use in a low temperature tank, comprising: 
 a plurality of beams;    a plurality of support bars connected to the plurality of beams;    a plurality of metal sheets, wherein an external portion of each of the plurality of metal sheets rests on one of the plurality of support bars and the plurality of metal sheets cover openings between the plurality of support bars;    a plurality of clamping bars, wherein each of the plurality of clamping bars engages a top surface of at least one of the plurality of metal sheets; and    a plurality of fasteners, wherein at least one of the plurality of fasteners secures at least one of the plurality of clamping bars to at least one of the plurality of support bars.    
   
   
       2 . The insulation deck of  claim 1 , further comprising a termination member extending around the edge of the insulation deck.  
   
   
       3 . The insulation deck of  claim 1 , wherein the plurality of fasteners are lock bolts.  
   
   
       4 . The insulation deck of  claim 1 , wherein the plurality of fasteners are mechanically locked in place.  
   
   
       5 . The insulation deck of  claim 1 , wherein the plurality of beams are aligned substantially parallel and wherein the plurality of support bars are aligned substantially parallel and substantially transverse to the plurality of beams.  
   
   
       6 . The insulation deck of  claim 5 , wherein the plurality of substantially parallel beams, the plurality of substantially parallel support bars, the plurality of metal sheets, the plurality of clamping bars, and the plurality of fasteners are each comprised of an aluminum alloy.  
   
   
       7 . The insulation deck of  claim 6 , further comprising means for suspending the insulation deck from the roof of the low temperature tank.  
   
   
       8 . The insulation of deck of  claim 7 , wherein the means for suspending the insulation deck is connected to the plurality of beams.  
   
   
       9 . The insulation deck of  claim 7 , wherein the plurality of fasteners connect the means for suspending the insulation deck to the plurality of support bars or to the plurality of clamping bars  
   
   
       10 . The insulation deck of  claim 7 , wherein the means for suspending the insulation deck is metal bars or structural beams.  
   
   
       11 . The insulation deck of  claim 7 , wherein the means for suspending the insulation deck is metal cables.  
   
   
       12 . The insulation deck of  claim 11 , wherein the metal cables further comprise stainless steel cables.  
   
   
       13 . The insulation deck of  claim 6 , wherein the insulation deck is suspended from the roof of the low temperature tank from the group consisting of metal bars, structural beams, or metal cables.  
   
   
       14 . The insulation deck of  claim 1 , wherein at least one of the plurality of support bars has at least one rib and at least one of the plurality of clamping bars has at least one groove that mates with the at least one rib such that at least a portion of one of the plurality of metal sheets is pressed into the groove by the rib when at least one of the plurality of fasteners is tightened.  
   
   
       15 . The insulation deck of  claim 1 , wherein at least one of the plurality of support bars has at least one groove and at least one of the plurality of clamping bars has at least one rib that mates with the at least one groove such that at least a portion of one of the plurality of metal sheets is pressed into the groove by the rib when at least one of the plurality of fasteners is tightened.  
   
   
       16 . The insulation deck of  claim 1 , wherein the plurality of support beams and the plurality of clamping beams have interfitting convex and concave surfaces.  
   
   
       17 . The insulation deck of  claim 16 , wherein at least two adjacent metal sheets of the plurality of metal sheets overlap such that a portion of the metal sheet rests between the concave and convex surfaces.  
   
   
       18 . The insulation deck of  claim 17 , wherein at least one of the plurality of clamping bars and at least one of the plurality of support beams partially deforms a portion of the metal sheets when at least one of the plurality of fasteners is tightened.  
   
   
       19 . The insulation deck of  claim 18 , wherein the deformation of the portion of the metal sheets creates a metal-to-metal seal.  
   
   
       20 . The insulation deck of  claim 1 , wherein the plurality of beams, the plurality of support bars, the plurality of metal sheets, the plurality of clamping bars, and the plurality of fasteners are each comprised of the same material.  
   
   
       21 . The insulation deck of  claim 1 , wherein at least one of the plurality of support bars further comprises a channel running along the support bar.  
   
   
       22 . The insulation deck of  claim 21 , wherein at least one of the plurality of clamping bars at least partially deforms a portion of one of the plurality metal sheets into the channel running along the support bar.  
   
   
       23 . The insulation deck of  claim 1 , wherein the plurality of fasteners are tightened such that the plurality of clamping bars and the plurality of support bars causes the plurality of metal sheets to be a stressed membrane.  
   
   
       24 . The insulation deck of  claim 23 , further comprising insulation supported by the stressed membrane.  
   
   
       25 . The insulation deck of  claim 24 , wherein the insulation is a powder.  
   
   
       26 . The insulation deck of  claim 1 , further comprising insulation supported on the plurality of metal sheets.  
   
   
       27 . The insulation deck of  claim 26 , wherein the insulation is a powder.  
   
   
       28 . The insulation deck of  claim 27 , wherein the insulation is perlite.  
   
   
       29 . The method of constructing an insulation deck for use in a low temperature tank, comprising: 
 attaching a plurality of substantially parallel beams to the roof of the low temperature tank;    attaching a plurality of substantially parallel support bars to the plurality of substantially parallel beams, wherein the plurality of support bars extend transverse to the plurality of beams;    placing a plurality of metal sheets across the openings between the plurality of support bars;    placing a plurality of clamping bars on the plurality of metal sheets, wherein the plurality of clamping bars are located above the plurality of support bars;    deforming at least a portion of the plurality of metal sheets by tightening a plurality of fasteners, wherein the plurality of fasteners secure together the plurality of support bars, the plurality of metal sheets, and the plurality of clamping bars;    attaching a sealing member that extends from the edge of the insulation deck to the sides of the low temperature tank; and    installing insulation on top of the insulation deck.    
   
   
       30 . The method of  claim 29 , wherein each of the plurality of substantially parallel beams, the plurality of substantially parallel support bars, the plurality metal sheets, the plurality of clamping bars, and the plurality of fasteners are comprised of aluminum.  
   
   
       31 . The method of  claim 29 , wherein the insulation is a powder.  
   
   
       32 . The method of  claim 31 , wherein the insulation is perlite.  
   
   
       33 . The method of  claim 29 , wherein the plurality of metal sheets are a stressed membrane.  
   
   
       34 . The method of  claim 29 , further comprising the step of overlapping the edges of the plurality of metal sheets.  
   
   
       35 . The method of  claim 34 , wherein the at least a portion of the plurality of metal sheets that is deformed is the overlapping edges of the plurality of metal sheets.