Abstract:
A header and coil connection assembly is provided for a heat exchanger. The header is comprised of a first section of a generally half cylindrical structure and a second section of a generally half cylindrical structure. The second section has a plurality of openings each of which receives a heat exchanger tube. The heat exchanger tubes are connected to the second section by welding around the opening.

Description:
BACKGROUND OF INVENTION  
       [0001]     The present invention relates to an improved header and method for making a header for use in a heat exchanger or thermal storage device.  
         [0002]     Indirect fluid cooling arrangements are comprised of a plurality of tubular passageways immersed in a pool of liquid within a vessel. The pool of liquid itself is cooled, usually by the use of a cooling tower. In turn, the liquid passing through the plurality of tubular passageways is cooled by the indirect contact with the pool of cooled liquid.  
         [0003]     Such a fluid cooling arrangement is similar to an ice storage arrangement. In an ice storage arrangement, a refrigerant liquid is provided from a mechanical refrigeration unit through a plurality of tubular passageways immersed in a pool of liquid within a vessel. The refrigerant acts to form ice about the tubular passageways from the pool of liquid, which is usually water. During supplemental cooling, the refrigerant liquid itself is circulated through the plurality of tubular passageways after the refrigerant has been warmed by passing through a heat exchanger in an air conditioning or cooling system. Such a refrigerant is thusly sub-cooled by passing through the ice surrounded passageways. The refrigerant in turn melts the ice surrounding the passageways. This is the concept of ice thermal storage.  
       SUMMARY OF THE INVENTION  
       [0004]     Accordingly, it is an object of the present invention to provide an improved header for use in a heat exchanger or thermal storage device.  
         [0005]     A header and tubular coil connection assembly is provided for use in a heat exchanger or ice thermal storage device. The header is comprised of a first section of a generally half cylindrical structure, and a second section of a generally half cylindrical structure. Each of the first and second sections are formed of an elongated structure, typically formed into a half cylindrical or nearly half cylindrical structure in a bending operation. It is within the scope of the present invention to provide a generally half cylindrical structure utilizing multiple bends that approach a purely half cylindrical form.  
         [0006]     One of the first and second sections, which herein is referred to as a second section, includes a plurality of openings passing through the cylindrical structure. Due to the generally half cylindrical nature of the first and second sections, one side of each of the first and second sections can be considered a concave side, while the other side is considered a convex side. The second section has a plurality of openings, each of which receives a heat exchanger tube. The heat exchanger tube end which passes through the opening is an end of the tubular passageway that forms the indirect heat exchanger or ice thermal storage coil. Each heat exchanger tube is connected to the opening through which it passes by a suitable means, which in the case of galvanized steel heat exchanger tubes and header sections, usually is comprised of a welding operation. The welding usually is performed through the concave side of the second section, thereby allowing the end of the heat exchanger tube to be readily visible to the welder, allowing a complete and uninterrupted weld to be formed about the heat exchanger tube and opening. Such a continuous weld is important to assure a leakproof seal between the heat exchanger tube and the header section. 
     
    
     BRIEF DESCRIPTION OF THE DRAWINGS  
       [0007]     In the drawings,  
         [0008]      FIG. 1  is a perspective view of a heat exchanger with a first embodiment of a header section in accordance with the present invention;  
         [0009]      FIG. 2  is a perspective view of the header section of the first of embodiment of the header section;  
         [0010]      FIG. 3  is a side view of the first embodiment of the header section;  
         [0011]      FIG. 4  is a perspective view of a heat exchanger assembly utilizing a second embodiment of the header of the present invention;  
         [0012]      FIG. 5  is a perspective view of a second embodiment of a header section of the present invention;  
         [0013]     And  FIG. 6  is a side view of a second embodiment of the present invention. 
     
    
     DETAILED DESCRIPTION  
       [0014]     Referring now to  FIGS. 1-3 , a heat exchanger is shown generally at  10  as comprising structural support members  12 , and a plurality of tube circuits  14 . Structural supports  12  are usually comprised of galvanized steel or stainless steel, while heat exchanger tubes  14  can be comprised of galvanized steel, stainless steel, or other suitable materials such as copper. Ends of heat exchanger tubes  18  are seen to extend through openings  20  in second header section  16 . Header section  16  itself is usually comprised of galvanized steel, but can be comprised of stainless steel or other suitable materials such as copper.  
         [0015]     Tubing ends  18  are seen to extend through openings  20  in second header section  16 . Second header  16  itself is seen to be comprised of an elongated, generally half cylindrical shaped structure. Second header section  16  includes top edge  22  and bottom edge  24 , which extend the length of second header section  16 . Further, second header section  16  is seen to have a concave side  26  and a convex side  28 . Further, as shown in  FIG. 1 , first header section  29  is seen to be assembled against second header section  16 . First header section  29  is similar to second header section  16 , except that it usually does not have openings to receive heat exchanger tubes therein. In all other respects, first header section  29  is similar in shape and material to second header section  16 .  
         [0016]     In assembling heat exchanger  10 , heat exchanger tubes  14  are spaced and placed within structural supports  12 . The ends  18  of heat exchanger tubes  14  are then placed through openings in second header section  16 . A continuous weld is them formed around the section of tubing end  18  that directly passes through and is adjacent opening  20 . In this manner, by forming the welding of concave side  26  of second header section  16 , a continuous weldment is formed about tubing end  18  to ensure a complete and watertight weld. From an access point of view, it is seen to be difficult to perform welding about the tubing end  18  at convex side  28  of second header section  16 , but it is possible to perform welding at certain of tubing end of convex side  28 . However, it is seen to be preferable to perform welding from an access point of view and a continuity point of view from concave side  26  of second header section  16 .  
         [0017]     In the last step of assembling heat exchanger  10 , first header section  29  is placed such that its top and bottom edges contact, respectively, top edge  22  and bottom edge  24  of second header edge  16 . Then appropriate welding is performed along the junction of such edges again to produce a watertight seal between first header section  29  and second header section  16 .  
         [0018]     Referring now to  FIGS. 4-6 , a heat exchanger is shown generally at  30  as comprising structural support members  32 , and a plurality of tube circuits  34 . Structural supports  32  are usually comprised of galvanized steel or stainless steel, while heat exchanger tubes  34  can be comprised of galvanized steel, stainless steel, or other suitable materials such as copper. Ends of heat exchanger tubes  38  are seen to extend through openings  40  in first heat and second header section  36 . Header section  36  itself is usually comprised of galvanized steel, but can be comprised of stainless steel or other suitable materials such as copper.  
         [0019]     Tubing ends  38  are seen to extend through openings  40  in second header section  36 . Second header section  36  itself is seen to be comprised of an elongated, generally half cylindrical shaped structure. Second header section  36  includes top edge  42  and bottom edge  44 , which extend the length of second header section  36 . Further, second header section  36  is seen to have a concave side  46  and a convex side  48 . Further, as shown in  FIG. 4 , first header section  49  is seen to be assembled against second header section  36 . First header section  49  is similar to second header section  36 , except that it usually does not have openings to receive heat exchanger tubes therein. In all other respects, first header section  49  is similar in shape and material to second header section  36 .  
         [0020]     In assembling heat exchanger  30 , heat exchanger tubes  34  are spaced and placed within structural supports  32 . The ends  38  of heat exchanger tubes  34  are then placed through openings  40  in second header section  36 . A continuous weld is them formed around the section of tubing end  38  that directly passes through and is adjacent opening  40 . In this manner, by forming the welding of concave side  46  of second header section  36 , a continuous weldment is formed about tubing end  38  to ensure a complete and watertight weld. From an access point of view, it is seen to be difficult to perform welding about the tubing end  38  at convex side  48  of second header section  36 , but it is possible to perform welding at certain of tubing end of convex side  48 . However, it is seen to be preferable to perform welding from an access point of view and a continuity point of view from concave side  46  of second header section  36 .  
         [0021]     In the last step of assembling heat exchanger  30 , first header section  49  is placed such that its top and bottom edge contact, respectively, top edge  42  and bottom edge  44  of second header edge  36 . Then appropriate welding is performed along the junction of such edges again to produce a watertight seal between first header section  49  and second header section  36 .