Abstract:
An air cooled condenser fan deck subassembly system and method including eight subassembly parts which are pre-assembled prior to arrival at the final assembly location. The eight subassembly parts include four inner subassembly parts and four outer subassembly parts, each of which are sized to fit in a standard sea container. Once the eight fan deck subassembly parts are delivered to the site, they are unloaded and bolded together, resulting in significant time and cost savings to the purchaser and erector.

Description:
[0001]    This application claims priority from U.S. Provisional Application No. 61/638,853, the disclosure of which is incorporated herein in its entirety. 
     
    
     FIELD OF THE INVENTION 
       [0002]    The present invention relates to air-cooled condensing systems and more particularly to an air cooled condensing system that maintains thermodynamic efficiency but is much simpler and cheaper in physical installation than the current state of the art air cooled condensing systems. 
       BACKGROUND OF THE INVENTION 
       [0003]    The frame assembly of large multi-street field erected air cooled condensers is a complex, labor-intensive, repetitive and potentially dangerous process. While sizes and relative dimensions vary widely, large scale field erected air cooled condensers often consist of as many as eight or more “streets,” each street having four or more fan units or “modules.”  FIG. 1  shows a portion of a typical air cooled condenser (ACC). 
         [0004]    Frame assembly is generally carried out according to a “stick” assembly process, where each individual piece of the frame is moved into place, one at a time, either by hand, or with assistance with a crane or lift, and sequentially bolted or otherwise fixed to adjacent pieces. As the frame rises into the air, workers climb up, down, and through already assembled portions of the frame to place and bolt new pieces. Hence, beginning from bottom to top, and from one side to the other, the frame is assembled manually, one piece at a time. For safety, workers use safety harnesses attached to already-assembled portions of the frame, and the harnesses need to be detached and moved to a different part of the frame and the assembly progresses. 
         [0005]    The portion of the structure supporting the fans, generally referred to as the fan deck, is generally assembled at ground level, then lifted via crane and placed at its final location, often fifty to ninety feet above ground, depending on the size and design of the ACC.  FIG. 2  is a view of the fan deck steel work looking up when standing at grade. The fan deck steel work is shown in cross-hatch. 
         [0006]    The steel parts that make up the fan deck are typically shipped from the manufacturing facility to the assembly location loose and singularly in standard sized sea containers. The steel frame parts that make up the fan deck can number up to forty or more pieces, see, e.g.,  FIG. 3 . Once they arrive at the site, the parts that make up the fan deck must be shaken out of the sea containers in which they are shipped, sorted, identified, and inventoried (sometimes collectively referred to as the “field shake”), all prior to assembly. 
         [0007]    These steps are laborious, time consuming, and expensive. Indeed, purchasers of ACCs, and the erectors who field assemble the ACCs at site, face very high costs to install them, and one of the contributory factors to the high cost of installation is the amount of labor it takes to do the field shake and the field bolting. In addition, many small pieces get lost and damaged and, as it is difficult to determine whether missing parts were lost at the assembly site or not shipped in the first place, ACC manufacturers often have to resupply both structural steel parts and more bolts at their own cost. 
         [0008]    There have been attempts at manufacturing fan deck subassemblies prior to shipping them to the project site, but such prior art fan deck subassemblies have always constituted corner quadrants. The corner quadrants were too big to ship in standard sea containers and therefore were shipped by break bulk. The corner quadrant design typically included twelve to sixteen pieces due to tie-in steel work that was required to connect each of the four corner quadrants after they were erected. 
       SUMMARY OF THE INVENTION 
       [0009]    This invention presents ACC fan deck subassembly designs, systems and methods that will result in substantially less material handling, less ground level field assembly and field bolting, and many fewer lifts with the crane. Accordingly, the present invention will make ACCs more attractive to purchase and erect. 
         [0010]    Instead of approximately forty separate fan deck parts being delivered to the field site for assembly into a prior art ACC fan deck, each fan deck according to an embodiment of the invention is assembled from eight subassembly parts which are pre-assembled prior to arrival at the final/field assembly location. According to one embodiment of the invention, the eight subassembly parts include four inner subassembly parts and four outer subassembly parts. Once the eight fan deck subassembly parts are delivered to the site, they are unloaded and bolted together, resulting in significant time and cost savings to the purchaser and erector. According to embodiments of the invention, while certain work is transferred to the manufacturing facility or other pre-assembly location, labor costs are typically much less expensive in a manufacturing facility or pre-assembly facility as compared to field erection labor costs. 
         [0011]    According to an embodiment of the invention, the ACC fan deck subassembly design and method saves on material costs, as field assembly bolts are replaced with shop welds, so the amount of field assembly hardware, e.g., bolts, nuts, etc., that is required for shipment to the field assembly location is reduced. 
         [0012]    According to an embodiment of the invention, the ACC fan deck subassembly parts are sized to fit into a standard size sea container. According to another embodiment of the invention, the ACC fan deck subassembly parts are sized to fit into a shipping container having outside dimensions of approximately 40 feet in length, 8 feet in width, and 9.5 feet in height. According to another embodiment, the ACC fan deck subassembly parts are sized to fit into a shipping container having outside dimensions of approximately 40 feet in length, 8 feet in width, and 8.5 feet in height. According to another embodiment, the ACC fan deck subassembly parts are sized to fit into a shipping container having outside dimensions of approximately 20 feet in length, 8 feet in width, and 8.5 feet in height. According to another embodiment, the ACC fan deck subassembly parts do not exceed approximately 39.4 feet in length, and approximately 8.8 feet in width. According to another embodiment, the ACC fan deck subassembly parts do not exceed approximately 7.8 feet in width. According to another embodiment, the ACC fan deck subassembly parts do not exceed approximately 19.3 feet in length. 
         [0013]    According to embodiments of the invention, the need for the loading, delivery, unloading, sorting, and inventory of forty or more different parts is eliminated. According to embodiments of the invention, large subassembly parts are fabricated at a manufacturing facility or pre-assembly facility by welding the separate smaller parts together before shipping to the final assembly/field erection site. 
         [0014]    According to an embodiment of the invention, field erection time is reduced due to the reduced time requirement for assembling only eight subassembly parts into an ACC fan deck as compared to the time requirement for unloading, sorting, inventorying, and field assembling (generally bolting) forty or more parts into an ACC fan deck. 
         [0015]    According to an embodiment of the invention, as much as 80% of the fan deck surface plates can be attached to the subassembly parts at ground level rather than at fan deck level. 
         [0016]    According to an embodiment of the invention, many fewer crane lifts of fan deck parts are required, shortening the rental time and costs associated with crane rental at site. According to another embodiment of the invention, less work at height is required, resulting in increased safety and time and cost reductions. 
     
    
     
       DESCRIPTION OF THE DRAWINGS 
         [0017]    The subsequent description of the preferred embodiments of the present invention refers to the attached drawings, wherein: 
           [0018]      FIG. 1  is a representation of a portion of an air cooled condenser structure. 
           [0019]      FIG. 2  is a representation of an underside view of a fan deck assembly of an air cooled condenser module. The cross-hatched elements represent the fan deck assembly, and the speckled elements represent the fan deck support structure. 
           [0020]      FIG. 3A  shows the individual parts of a prior art fan deck arranged to show their relative positions in the fan deck. 
           [0021]      FIG. 3B  shows an assembled prior art fan deck using the parts shown in  FIG. 3A . 
           [0022]      FIG. 3C  shows the assembled fan deck of  FIG. 3B  placed on top of its corresponding ACC module support structure. 
           [0023]      FIG. 4A  is shows fan deck subassembly parts according to an embodiment of the invention, arranged to show their relative positions in the fully assembled fan deck. 
           [0024]      FIG. 4B  shows a fan deck according to an embodiment of the invention, assembled from the subassembly parts shown in  FIG. 4A . 
           [0025]      FIG. 4C  shows the assembled fan deck of  FIG. 4B  placed on top of its corresponding ACC module support structure. 
           [0026]      FIG. 5A  is shows fan deck subassembly parts according to another embodiment of the invention, arranged to show their relative positions in the fully assembled fan deck. 
           [0027]      FIG. 5B  shows a fan deck according to an embodiment of the invention, assembled from the subassembly parts shown in  FIG. 5A . 
           [0028]      FIG. 5C  shows the assembled fan deck of  FIG. 5B  placed on top of its corresponding ACC module support structure. 
       
    
    
     DETAILED DESCRIPTION OF THE INVENTION 
       [0029]    In the following description, numerous details are set forth to provide a more thorough explanation of the present invention. It will be apparent, however, to one skilled in the art, that the present invention may be practiced without these specific details. 
         [0030]    The general structure of an air cooled condenser  2  is shown in  FIG. 1 , including the location of fan deck  4 . 
         [0031]      FIG. 4A  shows an eight part fan deck subassembly including outer subassembly parts  12   a,    12   b,    12   c,  and  12   d,  and inner subassembly parts  14   a,    14   b,    14   c  and  14   d.  Each of the subassembly parts are assembled prior to delivery to the field assembly location, and are preferably sized to fit into a standard shipping container having outer dimensions of 40 feet, by 8 feet, by 9.5 feet. 
         [0032]    According to one embodiment of the invention, each of outer subassembly parts  12   a ,  12   b,    12   c  and  12   d  is different from the other. According to yet another embodiment of the invention, outer subassembly parts  12   a  and  12   c  are interchangeable with one-another, but not with subassembly parts  12   b  and  12   d.  According to another embodiment, outer subassembly parts  12   b  and  12   d  are interchangeable with one-another, but not with subassembly parts  12   a  and  12   c.  According to another embodiment of the invention, each of outer subassembly parts  12   a ,  12   b,    12   c  and  12   d  are identical to one-another. According to another embodiment of the invention, two or more of outer subassembly parts  12   a,    12   b,    12   c  and  12   d  are substantially identical to one-another. According to another embodiment of the invention, each of outer subassembly parts  12   a,    12   b,    12   c  and  12   d  are interchangeable. 
         [0033]    According to one embodiment of the invention, each of inner subassembly parts  14   a ,  14   b,    14   c  and  14   d  is different from the other. According to yet another embodiment of the invention, inner subassembly parts  14   a  and  14   c  are interchangeable with one-another, but not with subassembly parts  14   b  and  14   d.  According to yet another embodiment, inner subassembly parts  14   b  and  14   d  are interchangeable with one-another, but not with subassembly parts  14   a  and  14   c.  According to another embodiment of the invention, inner subassembly parts  14   a,    14   b,    14   c  and  14   d  are identical to one-another. According to another embodiment of the invention, two or more of outer subassembly parts  14   a,    14   b,    14   c  and  14   d  are substantially identical to one-another. According to another embodiment of the invention, inner subassembly parts  14   a,    14   b ,  14   c  and  14   d  are interchangeable with one-another. 
         [0034]    According to an embodiment of the invention, inner subassembly parts  14   a,    14   b,    14   c  and  14   d  each have an end structure or connect point  24  at each end. According to this embodiment, the end structure  24  of one inner subassembly part is bolted at the field assembly site to the end structure  24  of an adjacent inner subassembly part to form a fan deck corner structure. According to an embodiment of the invention, end structures  24  are generally triangular shaped. 
         [0035]    As described above, fan deck subassembly parts  12   a - 12   d  and  14   a - 14   d  are assembled at a manufacturing or pre-field-assembly location. According to one embodiment of the invention, the constituent pieces of the subassembly parts are shop-welded to one-another. Once manufactured, the subassembly parts are shipped to the field assembly location in standard sized shipping containers. At the field assembly location, the subassembly parts may be bolted to one-another on the ground to form the assembled fan deck assembly  10  ( FIG. 4B ), and the assembled unit can be crane-lifted into its final location atop the fan deck support structure  16  ( FIG. 4C ). 
         [0036]      FIG. 5A  shows an eight part fan deck subassembly for a larger-sized ACC fan deck where some of the subassembly component parts present on the inner subassembly parts of  FIG. 4A  are shifted to outer subassembly parts, as with increasing fan deck size, the width of the internal subassemblies become too large to fit into a standard sized shipping container. According to the embodiment shown in  FIG. 5A , the invention includes outer subassembly parts  20   a,    20   b,    20   c,  and  20   d,  and inner subassembly parts  22   a,    22   b,    22   c  and  22   d.  Each of the subassembly parts are assembled prior to delivery to the field assembly location, and are preferably sized to fit into a standard shipping container having outer dimensions of 40 feet, by 8 feet, by 9.5 feet. Thus, according to this embodiment, the overall size of the finished fan deck can be increased, without increasing the size of any single subassembly part beyond the capacity of a standard shipping container. 
         [0037]    According to one embodiment of the invention, each of outer subassembly parts  20   a ,  20   b,    20   c  and  20   d  is different from the other. According to another embodiment of the invention, outer subassembly parts  20   a  and  20   c  are interchangeable with one-another, but not with subassembly parts  20   b  and  20   d.  According to another embodiment, outer subassembly parts  20   b  and  20   d  are interchangeable with one-another, but not with subassembly parts  20   a  and  20   c.  According to yet another embodiment of the invention, outer subassembly parts  20   a,    20   b ,  20   c  and  20   d  are identical to one-another. According to another embodiment of the invention, two or more of outer subassembly parts  20   a,    20   b,    20   c  and  20   d  are substantially identical to one-another. According to yet another embodiment of the invention, outer subassembly parts  20   a ,  20   b,    20   c  and  20   d  are interchangeable with one-another. 
         [0038]    According to one embodiment of the invention, each of inner subassembly parts  22   a ,  22   b,    22   c  and  22   d  is different from the other. According to another embodiment of the invention, inner subassembly parts  22   a  and  22   c  are interchangeable with one-another, but not with subassembly parts  22   b  and  22   d.  According to another embodiment of the invention, inner subassembly parts  22   b  and  22   d  are interchangeable with one-another, but not with subassembly parts  22   a  and  22   c.  According to yet another embodiment of the invention, inner subassembly parts  22   a,    22   b,    22   c  and  22   d  are identical to one-another. According to another embodiment of the invention, two or more of inner subassembly parts  22   a,    22   b,    22   c  and  22   d  are substantially identical to one-another. According to yet another embodiment of the invention, inner subassembly parts  22   a,    22   b,    22   c  and  22   d  are interchangeable. 
         [0039]    According to an embodiment of the invention, inner subassembly parts  22   a,    22   b,    22   c  and  22   d  each have an end structure or connect point  26  at each end. According to this embodiment, the end structure  26  of one inner subassembly part is bolted at the field assembly site to the end structure  26  of an adjacent inner subassembly part to form a fan deck corner structure. According to an embodiment of the invention, end structures  26  are generally triangular shaped. 
         [0040]    As described above, fan deck subassembly parts  20   a - 20   d  and  22   a - 22   d  are assembled at a manufacturing or pre-field-assembly location. According to one embodiment of the invention, the constituent pieces of the subassembly parts are shop-welded to one-another. Once manufactured, the subassembly parts are shipped to the field assembly location in standard sized shipping containers. At the field assembly location, the subassembly parts may be bolted to one-another on the ground to form the assembled fan deck assembly  18  ( FIG. 5B ), and the assembled unit can be crane-lifted into its final location atop the fan deck support structure  16  ( FIG. 5C ). 
         [0041]    Other arrangements in addition to those shown in  FIGS. 4A and 5A  are possible without departing from the central feature of the invention, namely eight-part fan deck subassemblies that are assembled at a location remote from the field assembly/erection location, and which can be shipped to the field assembly location in standard-sized shipping containers for a much-simpler and much less expensive field location fan deck assembly. In addition, while not falling within the most preferred embodiments of the invention, the invention is considered to include minor changes to the subassembly concept described herein, such as nine-part, ten-part, eleven-part, and twelve-part subassemblies, for example, by merely adding one or more unnecessary subassembly parts, or by breaking one or more larger subassembly parts into two or more parts, in order to avoid an eight-part fan deck subassembly package. Additionally, the invention includes fan deck subassembly systems including eight to twelve large subassembly parts, each of which are anywhere from approximately 50%, 60%, 70% or 80% to 100% the length or width of a fully assembled fan deck, and a plurality of smaller subassembly parts that are connected to the eight to twelve large subassembly parts to make the complete fan deck. Accordingly, the invention is considered to include eight-part, nine-part, ten-part, eleven-part and twelve-part fan deck subassemblies, as well as up to twenty-part fan deck subassemblies, provided that each subassembly part is dimensioned so that it can be shipped in a standard sea container.