Support Assemblies and Systems for Semi-Membrane Tanks

Abstract

Support assemblies for attaching the walls and top of a semi-membrane tank to surrounding support structure include interlocked angled sliding surfaces, whereby movement perpendicular to the walls and top is permitted as well as movement along one line or two perpendicular lines parallel to the tank sides and top. Arrayed on the surfaces of the walls and tops, these support assemblies provide the necessary support for the tank walls and top while minimizes thermal stresses in the tank. Support systems comprising such arrays, surrounding support structure, and tank insulation can be assembled outside a ship and engagingly lowered into a compartment therein, facilitating construction.

1 . A support assembly for attaching a wall or top of a semi-membrane tank to a surrounding support structure, said assembly comprising a first member fixedly attachable to the surrounding support structure, and a second member fixedly attachable to the tank wall or top, wherein the first and second members include interlocked complementary angled ramp surfaces slidably engaged in a manner which permits movement of the second member relative to the first member in a direction parallel to the axis of the ramping surfaces and prevents movement of the second member relative to the first member in a direction perpendicular to the ramping surfaces.  
   
   
       2 . The support assembly according to  claim 1  wherein the interlocked complementary angled ramp surfaces are slidingly engaged in a manner which prevents movement of the second member relative to the first member in the cross-ramp direction.  
   
   
       3 . The support assembly according to  claim 1  wherein the interlocked complementary angled ramp surfaces are slidably engaged in a manner which permits movement of the second member relative to the first member in the cross-ramp direction.  
   
   
       4 . The support assembly according to  claim 1  wherein the second member is rigidly attachable to the wall or top through load bearing insulation.  
   
   
       5 . The support assembly according to  claim 4 , wherein said load bearing insulation is a block comprising two pieces securable to one another.  
   
   
       6 . The support assembly according to  claim 4  wherein said load bearing insulation includes a notch conforming to the shape of a securing structure projecting outwardly from the tank wall or top.  
   
   
       7 . The support assembly according to  claim 1  wherein the second member is adapted to secure insulation panels to the tank.  
   
   
       8 . A support system for planar walls of a semi-membrane tank, said support system providing at least one point of thermal fixity for each wall, comprising a vertically extending support structure surrounding the tank and an array of support assemblies spaced over the outer surface of each wall connecting the wall to the surrounding support structure, said array including a plurality of support assemblies according to  claim 2  spaced horizontally from the at least one point of thermal fixity and oriented horizontally with their second members ramping away from said at least one point, thereby providing vertical support for each wall and permitting the second members to move perpendicularly to the plane of the wall and horizontally in the ramp direction parallel to the plane of the wall.  
   
   
       9 . The support system for planar walls of a semi-membrane tank, said support system providing at least one point of thermal fixity for each wall, comprising a vertically extending support structure surrounding the tank and an array of support assemblies spaced over the outer surface of each wall connecting the wall to the surrounding support structure, said array including a plurality of support assemblies according to  claim 3  spaced horizontally from the at least one point of thermal fixity and oriented horizontally with their second members ramping away from said at least one point, thereby providing vertical support for each wall and permitting the second members to move perpendicularly to the plane of the wall and horizontally in the ramp direction parallel to the plane of the wall.  
   
   
       10 . The support system according to  claim 9  wherein the walls each have one point of thermal fixity having no rigid attachment connecting the tank wall to the surrounding support structure.  
   
   
       11 . The support system according to  claim 10  wherein the point of thermal fixity of each wall is at its approximate horizontal midpoint and proximate its vertical low point, and wherein the array of supports spaced over the outer surfaces of each wall includes a plurality of support assemblies according to  claim 2  spaced radially from, and disposed such that they ramp away from, the point of thermal fixity.  
   
   
       12 . The support system according to  claim 8  wherein the support assemblies according to  claim 1  are disposed such that their second members ramp away from a line extending vertically through the at least one point of thermal fixity.  
   
   
       13 . The support system according to  claim 8  wherein the support assemblies are rigidly attachable to the walls through load-bearing insulation.  
   
   
       14 . The support system according to  claim 8  wherein said walls are of curved-plate construction with horizontally extending cusps between curved-plates, said array consisting of support assemblies according to  claim 2  arranged along said cusps.  
   
   
       15 . The support system according to  claim 14  wherein the support assemblies are arranged so as to form vertical columns of support assemblies.  
   
   
       16 . The support system according to  claim 15  further comprising vertically oriented structural beams, each beam being fixedly attached to the second member of at least two support assemblies in a vertical column of support assemblies.  
   
   
       17 . The support system according to  claim 8  wherein the tank includes a top and the surrounding support structure includes a horizontally extending top support structure above the top of the tank, further comprising an array of support assemblies according to  claim 1  spaced radially over the surface of the top and providing a point of thermal fixity, said support assemblies having first members rigidly attached to the surrounding support structure and having second members attached to the top with ramping surfaces oriented radially away from the point of rigid attachment.  
   
   
       18 . The support system according to  claim 17  wherein the second members are rigidly attached to the top through load-bearing insulation.  
   
   
       19 . The support system according to  claim 8  wherein the tank includes a top and the surrounding support structure includes a horizontally extending top support structure above the top of the tank, further comprising a rigid attachment rigidly securing a point of said top to said top support structure, and support assemblies according to  claim 1  arrayed in a grid pattern across the top.  
   
   
       20 . The support system according to  claim 8  further including vertical keys and engageable keyways attached to two or more parallel side walls and their respective surrounding support structure.