Basket for heat transfer elements for a rotary air preheater

Abstract

A basket for an air preheater includes two metallic frames each having two corner pieces and two connector pieces. For each frame, one of the connector pieces is secured to one end of each of the corner pieces and another of the connector pieces is secured to an opposite end of each of the corner pieces thereby forming a rectangular opening in each frame. The basket includes two heavy gauge metallic sheets that are secured to the corner pieces, thereby spacing the frames equally apart from and parallel to one another thereby forming a channel between two of the sheets.

What is claimed is: 
     
         1 . A basket for receiving heat transfer elements for a rotary air preheater, the basket comprising:
 two metallic frames each having two elongate corner pieces and two elongate connector pieces, each of the corner pieces having a two leg angled cross section, for each frame one of the connector pieces is secured to one end of each of the corner pieces and another of the connector pieces is secured to an opposite end of each of the corner pieces such that the corner pieces are spaced apart from and parallel to one another and the connector pieces are spaced apart from and parallel to one another thereby forming a rectangular opening in each frame; and   two heavy gauge metallic sheets, each sheet having opposite edges secured longitudinally along one of the corner pieces, thereby spacing the frames equally apart from and parallel to one another thereby forming a channel between two of the sheets, the channel having a longitudinal axis that is parallel to and bounded by the corner pieces, the channel being configured to receive heat transfer elements having a flow direction coaxial with the channel.   
     
     
         2 . The basket of  claim 1 , wherein the heavy gauge sheets are 12 gauge. 
     
     
         3 . The basket of  claim 1 , further comprising:
 a metallic closure grid secured, at each opposing end of the channel, to two of the connector pieces and two of the sheets, the closure grid having a plurality of openings therein, the openings being configured to convey a flow of a fluid therethrough.   
     
     
         4 . The basket of  claim 1 , wherein each of the connector pieces is substantially flat. 
     
     
         5 . The basket of  claim 1 , wherein, the corner pieces each having two elongate sections, each elongate section extending outwardly from a bend at an angle from one another and wherein the angle is obtuse for two of the corner pieces and the angle is acute for two of the corner pieces. 
     
     
         6 . The basket of  claim 1 , wherein at least one of the securing:
 of opposite edges of each sheet longitudinally along of each of two of the corner pieces,   of one of the connector pieces to one end of each of the corner pieces and the securing of another of the connector pieces to an opposite end of each of the corner pieces, and   of the opposite edges of the sheets longitudinally along one of the corner pieces;   is by welding.   
     
     
         7 . The basket of  claim 4 , wherein the opposite edges each of the sheets is secured to an outside surface of the each of the respective elongate section of each of two of the corner pieces. 
     
     
         8 . The basket of  claim 1 , wherein outside surfaces of the connector pieces of each frame are coplanar with outside surfaces of one of the elongate sections of the corner pieces of the respective frame. 
     
     
         9 . The basket of  claim 1 , wherein two of the connector pieces of one of the frames are longer than two of the connector pieces of the other frame. 
     
     
         10 . The basket of  claim 2 , wherein the closure grid comprises:
 at least one closure strip secured to opposing ones of the connector pieces; and   at least one cross piece extending through and secured to the at least one closure strips and opposing ends of the at least one cross piece being secured to opposing ones of the sheets.   
     
     
         11 . The basket of  claim 1 , wherein the connector pieces and the corner pieces each have a width that is less than 5 percent of an overall width of the frame. 
     
     
         12 . The basket of  claim 1 , wherein the connector pieces and the corner pieces are positioned at a perimeter of the frame. 
     
     
         13 . The basket of  claim 1 , further comprising a plurality of heat transfer elements stacked upon one another and disposed therein. 
     
     
         14 . The basket of  claim 13 , wherein said heavy gauge metallic sheets form a barrier to prevent gas and air flow bypass around edges of the heat transfer elements in contact therewith to improve effectiveness of the plurality of heat transfer elements in the basket installed in the air preheater as compared to heat transfer elements in baskets with open lateral sides.