Load-Carrying Apparatus and Methods of Manufacture

Abstract

The invention relates to load-carrying apparatus, for example pallets and shipping containers, rotationally moulded from a plastics material filled with a mineral filler. Methods and apparatus for manufacturing the load-carrying apparatus are also described. In one embodiment, the load-carrying apparatus comprises a pallet formed in two halves as two pallet elements. The plastic, rotationally moulded pallet elements form a nested configuration when stacked in the same orientation, but interlock to form a double-sided pallet when one of the pallet elements is inverted.

1 - 231 . (canceled) 
     
     
         232 . A rotationally-moulded load-carrying apparatus for carrying a load of at least 50 kilograms, wherein the apparatus is manufactured substantially from a filled plastics material comprising:
 at least 10% by weight of a polymer; and   at least 25% by weight of a mineral filler material comprising sand; and   at least about 0.1% by weight but less than about 10% by weight unifier.   
     
     
         233 . Apparatus according to  claim 232 , wherein the polymer comprises polyethylene. 
     
     
         234 . Apparatus according to  claim 232 , wherein the filled plastics material comprises at least 25% by weight polymer. 
     
     
         235 . Apparatus according to  claim 232 , wherein the filled plastics material comprises from about 30% to about 70% by weight polymer and from about 70% to about 30% by weight mineral filler material. 
     
     
         236 . Apparatus according to  claim 232 , wherein the filled plastics material comprises at least about 0.25% by weight of unifier. 
     
     
         237 . Apparatus according to  claim 232 , wherein the filled plastics material comprises less than about 5% by weight unifier. 
     
     
         238 . Apparatus according to  claim 232 , wherein the unifier is pre-mixed with the mineral filler material. 
     
     
         239 . Apparatus according to  claim 232 , wherein the unifier comprises an internal lubricant. 
     
     
         240 . Apparatus according to  claim 239 , wherein the internal lubricant comprises a fatty acid amide. 
     
     
         241 . Apparatus according to  claim 240 , wherein the internal lubricant comprises a straight or branched C 12 -C 24  fatty acid amide. 
     
     
         242 . Apparatus according to  claim 241 , wherein the internal lubricant comprises stearamide. 
     
     
         243 . Apparatus according to  claim 239 , wherein the unifier further comprises an external lubricant. 
     
     
         244 . Apparatus according to  claim 239 , wherein the unifier comprises less than 20% by weight internal lubricant. 
     
     
         245 . Apparatus according to  claim 239 , wherein the unifier comprises about 10% by weight internal lubricant. 
     
     
         246 . Apparatus according to  claim 232 , wherein the apparatus is rotationally moulded substantially in one piece. 
     
     
         247 . Apparatus according to  claim 232 , wherein the apparatus comprises a pallet. 
     
     
         248 . Apparatus according to  claim 247 , wherein the pallet comprises a platform and a plurality of feet depending from the platform. 
     
     
         249 . Apparatus according to  claim 248 , wherein the feet of the pallet are regularly spaced over the lower surface of the platform. 
     
     
         250 . Apparatus according to  claim 248 , wherein the feet are arranged to enable lifting equipment to engage the pallet from any one of four directions. 
     
     
         251 . Apparatus according to  claim 248 , wherein at least one foot is arranged substantially at each corner of the platform of the pallet. 
     
     
         252 . Apparatus according to  claim 248 , wherein at least one foot is arranged substantially at the centre of the platform of the pallet. 
     
     
         253 . Apparatus according to  claim 248 , wherein at least one foot is arranged substantially at the centre of each edge of the platform of the pallet. 
     
     
         254 . Apparatus according to  claim 248 , wherein each foot has a recess in the lower surface of the foot. 
     
     
         255 . Apparatus according to  claim 246 , wherein the pallet comprises an outer skin layer having an upper surface and a lower surface. 
     
     
         256 . Apparatus according to  claim 255 , wherein the pallet further comprises an inner layer having a different composition to the outer skin layer. 
     
     
         257 . Apparatus according to  claim 256 , wherein the inner layer comprises a foaming agent. 
     
     
         258 . Apparatus according to  claim 256 , wherein the inner layer comprises at least 40% by weight of a mineral filler material. 
     
     
         259 . Apparatus according to  claim 255 , wherein the outer skin layer comprises more than about 50% by weight polymer. 
     
     
         260 . Apparatus according to  claim 259 , wherein the outer skin layer comprises about 60% by weight polymer. 
     
     
         261 . Apparatus according to  claim 256 , wherein the inner layer comprises about 60% by weight of a mineral filler material. 
     
     
         262 . Apparatus according to  claim 256  wherein the inner layer comprises a greater amount of filler by weight than the outer layer. 
     
     
         263 . Apparatus according to  claim 232 , wherein the filled plastics material further comprises a pigment. 
     
     
         264 . Apparatus according to  claim 232 , wherein the apparatus incorporates a remotely readable ID tag. 
     
     
         265 . Apparatus according to  claim 264 , wherein the ID tag is moulded into the surface of the apparatus. 
     
     
         266 . Apparatus according to  claim 233 , wherein the polymer comprises high density polyethylene (HDPE). 
     
     
         267 . Apparatus according to  claim 243 , wherein the external lubricant comprises a stearate. 
     
     
         268 . Apparatus according to  claim 246 , wherein the apparatus comprises a pallet. 
     
     
         269 . Apparatus according to  claim 264 , wherein the remotely readable ID tag is an RFID tag. 
     
     
         270 . Apparatus according to  claim 232 , wherein the apparatus is a freight container.