Welded, Laminated Apparatus, Methods of Making, and Methods of Using the Apparatus

Abstract

The invention describes methods of welding onto laminated devices using a low temperature welding process. Also described are laminated devices with welds that do not disrupt a brazed core block of sheets in the laminated devices. Novel laminated devices with welded features for servicing the devices are also described.

1 . Laminated apparatus comprising:
 a core block comprising sheets of metal bonded together, at least in part, by a braze composition disposed between the sheets;   a welding composition disposed on the core block and adhering to the braze composition;   wherein the welding composition has a composition that differs from the composition of the braze composition; and wherein the welding composition is diffused 2 mm or less into the core block.   
     
     
         2 . The apparatus of  claim 1  wherein the welding composition forms a continuous weld across more than one metal sheet and more than one of the braze composition disposed between the sheets. 
     
     
         3 . The apparatus of  claim 1  comprising fluid channels disposed in the sheets and inlets to the fluid channels disposed on edges of the sheets. 
     
     
         4 . The apparatus of  claim 3  having resistance to leakage such that, when the fluid channels are pressurized with N2 at 100 psig (6.9 bar gauge), the pressure decreases by less than 0.5 psi (0.034 bar) after 15 minutes. 
     
     
         5 . The apparatus of  claim 3  comprising:
 a first set of fluid channels wherein each channel comprises an inlet and an outlet; 
 a second set of fluid channels wherein each channel comprises an inlet and an outlet; 
 a first welded inlet manifold, a first welded outlet manifold; 
 a second welded inlet manifold, and a second welded outlet manifold; 
 wherein the first welded inlet manifold is in fluid communication with the inlets of the first set of fluid channels; 
 wherein the first welded outlet manifold is in fluid communication with the outlets of the first set of fluid channels; 
 wherein the second welded inlet manifold is in fluid communication with the inlets of the second set of fluid channels; 
 wherein the second welded outlet manifold is in fluid communication with the outlets of the second set of fluid channels; and 
 wherein each of the manifolds are connected to the core block by a welding composition wherein the welding composition has a composition that differs from the composition of the braze composition; and wherein the welding composition is diffused 2 mm or less into the core block. 
 
     
     
         6 . The apparatus of  claim 5  wherein at least 2 of the manifolds are welded to the core block on a same side of the core block. 
     
     
         7 . The apparatus of  claim 1  comprising subassemblies that have been diffusion bonded. 
     
     
         8 . A method of conducting a unit operation in the apparatus of  claim 1  comprising: passing a fluid into a channel in the core block and conducting a unit operation on the fluid in the core block. 
     
     
         9 . The method of  claim 8  wherein a first fluid is passed into a first set of inlets and into a first set of channels in the core block; a second fluid is passed into a second set of inlets and into a second set of channels in the core block; and wherein the first fluid and the second fluid flow in adjacent sheets within the core block and the first fluid exchanges heat with the second fluid in the core block. 
     
     
         10 . A method of welding a metal onto laminated apparatus, comprising:
 providing laminated apparatus comprising sheets of metal bonded together, at least in part, by a braze composition disposed between the sheets;   applying a metal onto the laminated apparatus by a welding technique wherein a wire moves in a reciprocating motion and wherein a spark is generated when the wire touches and/or is pulling away from the laminated apparatus; and   wherein molten metal is applied to the surface while the wire moves away from the surface.   
     
     
         11 . The method of  claim 10  wherein, within 30 seconds of active welding, and without liquid cooling, the temperature of the laminated article is 100° C. or less (preferably 50° C. or less) throughout the entire apparatus. 
     
     
         12 . The method of  claim 10  wherein a weld is formed at a rate of 25 cm per minute or greater. 
     
     
         13 . A method of repairing a crack comprising applying a metal according to the process of  claim 10  onto a crack in laminated apparatus. 
     
     
         14 - 19 . (canceled) 
     
     
         20 . The apparatus of  claim 1  further comprising a solid-walled enclosure that encloses plural apertures within a single, contiguous space on a side of the core block; wherein the solid-walled enclosure comprises a solid, continuous wall that is welded on one side to the core block by the welding composition. 
     
     
         21 . A process of operating the apparatus of claim  16 , comprising:
 opening the manifold while leaving the enclosure welded to the core block; and   performing service on the core block.   
     
     
         22 . The process of  claim 21  wherein the step of performing service comprises at least one of: regenerating catalyst, replacing catalyst, regenerating sorbent, replacing sorbent, cleaning, or diagnostic testing. 
     
     
         23 . The method of  claim 8  wherein the unit operation comprises a Fischer-Tropsch reaction.