Low profile plastic pallet

Abstract

A predominately thermoplastic pallet, for use with a fork lift device, is provided and includes a rectangular base including rails having metal reinforcing beams, eight spaced apart outer columns extending upwardly from the outer rails and one center column extending upwardly from the center of the base. The pallet also includes a top including a rectangular thermoplastic frame and a corrugated sheet metal deck, wherein the frame is attached, to the tops of the outer columns and wherein the deck is inset from the outer edge of the frame and wherein the pallet has dimensions and properties which include outside dimensions of about 40 inches by about 48 inches, two forklift device openings on each side of the pallet, each of which are at least 3.1 inches high and 12 inches wide and a pallet height or 5.56 inches or less.

1 . A predominately thermoplastic pallet, for use with a fork lift device, which comprises: 
 a rectangular base comprised of rails having metal reinforcing beams;    eight spaced apart outer columns extending upwardly from the outer rails and one center column extending upwardly from the center of the base;    a top comprised of a rectangular thermoplastic frame and a corrugated sheet metal deck;    wherein the frame is attached to the tops of the outer columns;    wherein the deck is inset from the outer edge of the frame;    wherein the pallet has dimensions and properties which include    (a) outside dimensions of about 40 inches (1020 mm) by about 48 inches (1220 mm),    (b) two forklift device openings on each side of the pallet, each of which are at least 3.1 inches (79 mm) high and 12 inches (305 mm) wide;    (c) a pallet height of 5.56 inches (141 mm) or less;    (d) a weight of less than 55 pounds (25 kg) or less; and,    (e) a racking creep strength such that, when the pallet deck is subjected to a uniform load of 2800 pounds (1270 kg) for a period of 720 hours at a temperature of 115° F. (46° C.), while the pallet is supported along opposing 48 inch (1220 mm) sides by rack beams which are spaced apart 45 inches (1145 mm), the center of the pallet deflects 0.8 inches (2 mm) or less.    
     
     
         2 . The pallet of  claim 1  wherein the pallet height is about 5.4 inches (13.7 mm) or less.  
     
     
         3 . The pallet of  claim 2  wherein the pallet height is about 4.9 inches (12.4 mm) or less.  
     
     
         4 . The pallet of  claim 1  having a stacked pallet density property which is greater than 2.2 pallets per vertical foot (7.2 pallets per meter).  
     
     
         5 . The pallet of  claim 1  having a stacked pallet density property which is greater than 2.3 pallets per vertical foot (7.54 pallets per meter).  
     
     
         6 . The pallet of  claim 1  wherein the top deck is comprised of corrugated aluminum sheet metal, and the base is comprised of steel beams.  
     
     
         7 . The pallet of  claim 4  wherein the top deck is comprised of corrugated aluminum sheet metal, and the base is comprised of steel beams.  
     
     
         8 . The pallet of  claim 5  wherein the pallet is comprised of 30 to 45 percent metal by weight.  
     
     
         9 . The pallet of  claim 1  wherein the pallet has a fire test property which meets Underwriters Laboratories fire test standard UL 2335.  
     
     
         10 . The pallet of  claim 1  wherein the height of each entry opening is at least 60 percent of the height of the pallet.  
     
     
         11 . The pallet of  claim 2 , wherein the top is less than 15 percent of the height of the pallet.  
     
     
         12 . The pallet of  claim 1 , wherein said two openings are at least 12.5 inches wide.  
     
     
         13 . The pallet of  claim 1 , wherein the weight of the pallet is less than 51 pounds.  
     
     
         14 . A GMA type pallet for use with a fork lift device which comprises: 
 a rectangular base comprised of outer rails arranged in a rectangular pattern and cross rails connecting the opposing side midpoints of the outer rails, the rails having steel reinforcing beams;    eight spaced apart outer columns extending upwardly from the outer rails and one center column extending upwardly from the center of the base;    a 40 inch by 48 inch top, attached to the outer columns; the top comprised of a thermoplastic rectangular frame, a subframe and a corrugated sheet metal deck;    wherein, the deck made of aluminum alloy sheet and has a circumscribing flange and at least three continuous corrugations running from one corner of the deck to a diagonally opposed corner of the deck;    wherein, the frame forms the periphery of the top and comprises bridges which span the spaces between the columns; wherein each bridge comprises a multiplicity of vertical ribs which bound closed cells within the bridge;    wherein the deck flange is attached to the subframe;    wherein the edges of the deck are spaced apart at least 4 inches from the exterior edges of the frame;    wherein the pallet is predominately comprised of a molded polyolefin selected from polyurethane and polypropylene and combinations thereof;    wherein the metal parts weigh less than 40 percent of the weight of the whole pallet; and    wherein the pallet has    (a) two forklift device openings on each side of the pallet, bounded by the bridges and the outer rails and adjacent outer columns, each opening having a height of at least about 3.1 inches (79 mm) and a width of 12 inches (305 mm);    (b) a height less not exceeding 5.5 inches (141 mm); and    (c) a stacked pallet density property which is greater than 2.2 pallets per vertical foot (7.2 pallets per meter).    
     
     
         15 . The pallet of  claim 14 , having further properties which comprise: 
 (d) a racking creep strength such that, when the pallet deck is subjected to a uniform load of 2800 pounds (1270 kg) for a period of 720 hours at a temperature of 115° F. (46° C.), while the pallet is supported along opposing 48 inch (1220 mm) sides by rack beams which are spaced apart 45 inches (1145 mm), the center of the pallet deflects 0.8 inches (2 mm) or less; and,    (e) a fire test performance which meets Underwriters Laboratories fire test standard UL 2335.    
     
     
         16 . The method of making a GMA type thermoplastic pallet, wherein the pallet has a top mounted on columns extending upwardly from the base, wherein the pallet has properties which include (a) a racking creep strength such that, when the pallet deck is subjected to a uniform load of 2800 pounds (1270 kg) for a period of 720 hours at a temperature of 115° F. (46° C.), while the pallet is supported along opposing 48 inch (1220 mm) sides by rack beams which are spaced apart 45 inches (1145 mm), the center of the pallet deflects 0.8 inches (2 mm) or less; and (b) a fire test performance which meets Underwriters Laboratories fire test standard UL 2335, which comprises: providing the pallet base with steel reinforcing beams; providing the pallet with a top comprised of a plastic frame and a corrugated sheet metal deck which is inset from the outer edges of the frame and which has an area which is at least 75 percent of the area of the top of the pallet; wherein the corrugations of the deck comprise at least three of the corrugations which run diagonally from comer to comer of the deck; to thereby reduce the thermoplastic content of the deck to less than 70 percent of the weight of the pallet.