Because the steel wire rope looks very sturdy, but it needs regular butter maintenance. Have you checked the elevator? Is the wire rope thick enough? Regular maintenance must be carried out according to regulations, as well as weekly, monthly, quarterly, and semi annual inspections. Very troublesome.
What happens without maintenance? Will break
There are generally three types of wire rope breakage
The surface fracture is visible to the naked eye. Generally, if the length of the fracture point exceeds 6 times the diameter, it must be replaced. This kind of fracture is commonly seen in movies, and it is also the only intuitive fracture.
The valley fracture refers to the part of the inner side of the surface steel wire rope that is not easily visible, although visible, it is very concealed.
Internal fracture refers to the fracture of the steel wire rope core, which is generally not visible.
On the surface, the center of the sturdy steel wire rope may be broken, but only the surface is connected. In the movies, the kind of cutting is done from the outside to show you the fracture, but in reality, the fracture starts from the core.
Although there may be many issues with the stress toughness and other aspects of iron chains, all problems are superficial and can be solved as soon as problems are discovered, without the need for long-term dedicated testing.
The final key point is that the steel wire rope is used as an anchor chain. If any point is found to be broken, you cannot repair it. You can only dismantle the entire rope and replace it.
The iron chain is different. When a welding joint is broken, grab a welder and give it a thumbs up. As long as the craftsmanship is good, the welding strength can reach over 90% of the raw material stress. (I’m not very clear about the details on board, as my welder introduction said)
The thickest steel wire I have ever seen on a ship has a diameter of 12CM
It is a dredging engineering ship used to tow underwater construction equipment
Such thick steel wire
A naturally unstressed disk with a diameter of 7-8 meters
Winch approximately 2 meters
Anyway, it’s just one word
Hard and not easily bent.
If I use it as an anchor chain, I estimate I need to replace it every month
After all, anchoring is a process of pulling and pulling. A few tons of anchor crawls on the seabed, and when pulled, how long can the steel wire last
The main aspect is not the strength of the steel wire
The main reason for not using steel wire is the principle of anchoring
Anchors can hold the ship in place, relying mainly on the friction between the anchor and the anchor chain and the seabed
You can do an experiment
Tie a hook with a rope and drag it on the ground
What is the difference between letting out 1 meter of rope and letting out 10 meters
The heavier the anchor chain, the longer the released anchor chain, and the greater the frictional force on the seabed, the more difficult it is to anchor
At the same time, it is required that the anchor chain has good foldability. When the ship is anchored, it will constantly change direction with the wind. The steel wire is folded hard, not easy to fold, and is easy to break
According to this principle
Require the anchor chain to be folded and properly stored, with a large weight
Chain is the best choice