Whatever type of rope wire you choose, it is important to be aware of the properties and construction of it so that you are using the correct rope and also enhances your safety knowledge.
In manufacturing it, hundreds of tiny metal filaments are wrapped, twisted and braided together to make the inner wires. These will then turn into strands by twisting together the smaller inner wires / filaments. Twisting strands in various ways around a central core is what makes the wire rope. It is how they are twisted which gives them their differing properties e.g. non-rotating, low stretch, higher breaking strength. There are also different constructions depending on left and right hand lay.
Note: The numbers used when describing a rope denote the number of wires and strands within it. For example, a 6 x 36 wire rope has 6 strands made of 36 wires. Likewise, a 7 x 19 has 7 strands with 19 wires. Strength and/or flexibility is provided when the strands are twisted around an inner core which can be steel wire or fibre core.
Due to their construction, it’s important to identify any broken wires or strands which could have severe consequences if used without inspection and testing. However, if a few strands break during a specific lift, it is more likely the intact wires and strands will hold the load whilst it is safely lowered – then the rope can be destroyed. It is this property which makes them safer than chains because if a chain link breaks then the load will likely fall.
There are many factors which can affect them, including bad coiling using pulleys and sheaves etc., grooves that are too big or too small, excessive pulling angles or twisting the rope in the opposite way to its ‘lay construction’, dirt ingress and poor lubrication to name but a few.