Controlled failure rope systems and methods
AssigneeSamson Rope Technologies
InventorsWolfgang Wilke, Sigmunt Nowak, Danielle D. Stenvers, Chia-Te Chou
Life of this patent
Estimating the term…
Abstract
A controlled failure rope and method of making the same. The controlled failure rope comprises first and second portions. The first portion is formed of a first material having a first set of tension failure characteristics. The second portion is formed of a second material having a second set of tension failure characteristics. The first and second sets of tension failure characteristics differ such that, when the rope is subjected to tension loads above a tension threshold, the first portion of the rope begins to fail before the second portion of the rope, therefore providing a prior indication of possible rope failure before the rope becomes completed separated.
Claims30
A rope that fails in a predetermined manner when subjected to tension loads, comprising:
- a first material having a first set of tension failure characteristics, where the first material is combined into a first set of yarns that are combined into a first set of strands;
- and
- a second material having a second set of tension failure characteristics, where the second material is combined into a second set of yarns that are combined into a second set of strands;
- wherein
- the first and second sets of strands are combined to form the rope;
- the rope operates in
- a normal mode when the tension loads on the controlled failure rope are under a first tension threshold, where the first set of strands forms a primary strength component of the rope when the rope is operating in the normal mode,
- in a first stage of a failure sequence when the tension loads on the rope are above the first tension threshold and below a second tension threshold, where the material forming the first strands noticeably deforms in the first stage of the failure sequence;
- in a second stage of the failure sequence when the tension loads on the rope are above the second tension threshold, where the material forming the first set of strands fails and the second set of strands forms the primary strength component of the rope when the rope is operating in the second stage of the failure sequence;
- and
- the first tension threshold is below the second tension threshold.
A method of forming a rope having controlled failure characteristics when subjected to tension loads above a first tension threshold, the method comprising the steps of:
- providing a first rope material, where the first rope material defines a first set of tension failure characteristics;
- providing a second rope material, where the second rope material defines a second set of tension failure characteristics, where a load threshold of the first portion of the rope is lower than a load threshold of the second portion of the rope;
- forming a first set of yarns from the first material;
- forming a first set of strands from the first set of yarns;
- forming a second set of yarns from the second material;
- forming a second set of strands from the second set of yarns;
- combining the first and second sets of strands to form the rope such that
- when the rope is subjected to tension loads below the first tension threshold, the first set of strands forms a primary strength component of the rope under tension loads;
- and
- when the rope is subjected to tension loads above the first tension threshold and below a second tension threshold, the first material used to form the first set of strands noticeably deforms;
- and
- when the rope is subjected to tension loads above the second tension threshold, the material forming the first set of strands fails and the second set of strands forms the Primary strength component of the rope under tension loads.
Dependencies are inferred from the claim text.