Chain comprising a plurality of interconnected links
The invention relates to a chain suitable to moor or anchor boats, to lash cargo in road, rail, water and air transportation or for conveying, hoisting, suspending or lifting applications, said chain comprising a plurality of interconnected links. More in particular the invention relates to a chain suitable for the above stated uses comprising a plurality of interconnected links, at least part of the links comprising polyolefin fibers and in particular ultrahigh molecular weight polyethylene (UHMWPE) fibers. The invention also relates to a method for enhancing the strength of such a chain.
1. A chain suitable to moor or anchor boats, to lash cargo in road, rail, water and air transportation and for conveying, hoisting, suspending and lifting applications, said chain comprising a plurality of interconnected links, wherein at least part of the links comprise ultrahigh molecular weight polyethylene fibers.
2. The chain according to claim 1 , wherein the chain has a static strength of at least 1 kN.
3. The chain according to claim 1 , wherein the ultrahigh molecular weight polyethylene fibers have a tenacity of at least 1.9 N/tex.
4. The chain according to claim 1 , wherein at least part of the chain links comprise a cover.
5. The chain according to claim 1 , wherein at least part of the links comprise at least one of glass fibers, carbon fibers, metal fibers, aromatic polyamide fibers, poly(p-phenylene-2, 6-benzobisoxazole) (PBO) fibers, M5 fibers, and poly(tetrafluoroethylene) (PTFE) fibers.
6. The chain according to claim 1 , wherein the links comprise at least one of partly fused polyolefin filaments and staple fibers.
7. The chain according to claim 1 , wherein the links comprise straps of polyolefin fibers.
8. The chain according to claim 1 , wherein the interconnected links of the chain comprise interconnected endless loops.
9. The chain according to claim 8 , wherein the interconnected endless loops are interconnected by knots.
10. The chain according to claim 8 , wherein the interconnected endless loops are interconnected by tubular connecting means.
11. The chain according to claim 1 , wherein the chain comprises a ladder structure.
12. The chain according to claim 1 , wherein the links are interconnected by ring-shaped connecting means.
13. A method for enhancing the strength of a chain according to claim 1 , which method comprises pre-stretching the chain before use at a temperature below a melting temperature of the ultrahigh molecular weight polyethylene.
14. The method of claim 13 , wherein the chain is loaded with a static load of at least 20% of a breaking load of the chain, during a period sufficient to attain a permanent chain deformation of between 2 and 20%.
15. The method of claim 13 , wherein the chain is subjected to a number of load cycles ranging from 2-25, and wherein a maximum load applied to the chain is lower than 45% of a breaking load of the chain.
16. The method of claim 15 , wherein the chain is subjected to 5-15 load cycles, and wherein the maximum load applied to the chain is lower than 35% of the breaking load of the chain.
17. The method of claim 15 , wherein the chain is subjected to 8-12 load cycles, and wherein the maximum load applied to the chain is lower than 25% of the breaking load of the chain.