Endless shaped article

Abstract

Endless shaped articles include at least one strip of material forming a plurality of convolutions of the strip of material, the strip having a longitudinal axis, wherein each convolution of the strip comprises a twist along the longitudinal axis thereof, wherein the twist is an odd multiple of 180 degrees. Methods to manufacture the article, and its use as sling, loop, belt or chain link are also disclosed.

1 . An endless shaped article comprising:
 at least one single strip of material which forms a plurality of convolutions, wherein   the single strip of material has a longitudinal axis, and wherein   each of the convolutions of the single strip of material comprises a twist along the longitudinal axis such that each twist is an odd multiple of 180 degrees.   
     
     
         2 . The endless shaped article of  claim 1 , wherein the single strip of material comprises at least 2 convolutions, preferably at least 4, most preferably at least 8 convolutions. 
     
     
         3 . The endless shaped article of  claim 1 , wherein a difference in length between two adjacent convolutions of the single strip of material is less than 6 times, preferably less than 4 times, most preferably less than 2 times the thickness of the strip. 
     
     
         4 . The endless shaped article of  claim 1 , wherein lengths of each convolution differs from an average length of all convolutions by less than 6 times, preferably less than 4 times, most preferably less than 2 times the thickness of the single strip of material. 
     
     
         5 . The endless shaped article of  claim 1 , wherein the article has a density which is at least 70% of the density of the strip of material. 
     
     
         6 . The endless shaped article of  claim 1 , wherein the article is selected from the group consisting of a sling, a loop, a belt or a chain link. 
     
     
         7 . The endless shaped article of  claim 1 , wherein the single strip of material comprises a polyolefin, preferably an ultrahigh molecular weight polyolefin, most preferably an ultrahigh molecular weight polyethylene (UHMWPE). 
     
     
         8 . The endless shaped article of  claim 1 , wherein the single strip of material comprises an ultrahigh molecular weight polyethylene (UHMWPE) tape and/or yarn. 
     
     
         9 . The endless shaped article of  claim 1 , wherein single strip of material is a narrow weave. 
     
     
         10 . The endless shaped article of  claim 1 , which further comprises at least one fastening element to connect at least 2 convolutions to each other. 
     
     
         11 . The endless shaped article of  claim 1 , wherein the single strip of material includes opposed ends, and wherein the endless shaped article further comprises at least one fastening element connecting the opposed ends to one another. 
     
     
         12 . The endless shaped article of  claim 1 , wherein the single strip of material includes opposing ends which are overlapped along a first portion of a length of the single strip of material in each of at least four convolutions, and wherein the overlapped opposing ends are connected to one another. 
     
     
         13 . The endless shaped article of  claim 11 , wherein the single strip of material includes an opening across the convolutions, and wherein one of the opposed ends of the single strip of material reaches the other of the opposed ends through the opening. 
     
     
         14 . The endless shaped article of  claim 1 , wherein adjacent convolutions are at least partly fused to one another. 
     
     
         15 . An endless shaped article comprising:
 a single strip of material comprised of a length of woven fabric of ultrahigh molecular weight polyethylene (UHMWPE) yarn having opposing ends, wherein   the single strip of material is formed into a coil having at least four convolutions to provide at least four respective substantially overlapping layers that are superimposed upon one another, wherein   the coil has a longitudinal axis and a twist along the longitudinal axis which is an odd multiple of 180 degrees, and wherein   the opposing ends of the single strip of material are overlapped along a first portion of the length of the strip in each of the at least four convolutions, and wherein   the overlapped opposing ends are connected to one another.   
     
     
         16 . The endless shaped article of  claim 15 , wherein adjacent convolutions are at least partly fused to one another. 
     
     
         17 . The endless shaped article of  claim 15 , wherein at least 2 convolutions are connected to each other by at least one fastening element selected from the group consisting of stitching, glues, knotting, bolts, heat sealing, rivets and combinations thereof. 
     
     
         18 . A chain comprising a chain element, wherein the chain element comprises the endless shaped article according to  claim 1 . 
     
     
         19 . The chain according to  claim 18 , wherein the chain is a synthetic chain. 
     
     
         20 . The chain according to  claim 18 , wherein the convoluted strip comprises at least 4 convolutions. 
     
     
         21 . The chain according to  claim 18 , wherein in that a difference in length between two adjacent convolutions of the strip is less than 4 times the thickness of the strip. 
     
     
         22 . The chain according to  claim 18 , wherein the strip of material comprises UHMWPE tape and/or UHMWPE yarn. 
     
     
         23 . The chain according to  claim 18 , wherein at least 2 convolutions are connected to each other by at least one fastening element. 
     
     
         24 . The chain according to  claim 23 , wherein the at least one fastening element is selected from the group consisting of stitching, glues, knotting, bolts, heat sealing, rivets and combinations thereof. 
     
     
         25 . The chain according to  claim 18 , further comprising an adhesive layer or a coating between the convolutions. 
     
     
         26 . The chain according to  claim 18 , wherein the synthetic filaments are formed of a polymer selected from the group consisting of polyaramide, poly(p-phenylene terephthalamide), poly(p-phenylene-2, 6-benzobisoxazole) (PBO), liquid crystal polymer such as copolymers of para hydroxybenzoic acid and para hydroxynaphtalic acid, poly(2, 6-diimidazo-[4, 5b-4′, 5′e]pyridinylene-1, 4(2,5-dihydroxy)phenylene), ultrahigh molecular weight polyolefin and combinations thereof. 
     
     
         27 . A method for making an endless shaped article comprising the steps of:
 a) providing a single strip of material having a longitudinal axis,   b) twisting a first length of the strip of material by an odd multiple of 180 degrees about the longitudinal axis thereof,   c) forming a closed loop with the twisted first length by joining the length with a remaining portion of the strip of material, and   d) superimposing a further length of the strip of material onto the closed loop to provide a plurality of twisted convolutions of the strip.   
     
     
         28 . A method for making a synthetic chain which comprises forming a series of interconnected chain links, wherein each of the chain links comprises the endless shaped article according to  claim 15 . 
     
     
         29 . A method for making a synthetic chain which comprises forming a series of interconnected chain links, wherein each of the chain links comprises the endless shaped article according to  claim 1 .