Internal friction in steel wire rope

[Ivan Silva]

Hi folks, I had a class about friction while winding wire rope around a drum. I'll translate (it's in portuguese) and transcript a text about it:

A rope just can wind up around a drum when it takes the drum's shape due to it internal friction appears and it leads a deviation (it can be estimated, see the image 1) between the rope axis and an axis tangent to drum and parallel to the rope axis (Image 2). The main reasons which lead the internal friction are:

1. The compression of rope fiber next to the drum and tension of rope fiber furthest from the pulley

2. Sliding friction between the rope fibers

3. Elastic deformation of the material.

And this friction can be put into numbers by this formula (Image 3) and the amount of force required to wind up it by this another (Image 4). Given this introduction, my question is do you guys know something or meet this theory? I asked it because I was not able to find anything article about it. I think it is important to make you know the author of the book has passed away for more than one decade so the theory can be outdated.

 

[btrueblood]

It's based on practical experience, by measurement with a lot of different cable/rope sizes and lay patterns. It would be awfully difficult to model the internal friction in a rope from first principles.

 

[romke]

the internal friction is the result of the relative movement of the strands against each other when the cable is moved over a pulley or a drum. it will also depend on the way the cable is constructed - some designs might be better then others. another influence on the friction is the type of lubricant. during manufacturing the cables are impregnated with a lubricant that reduces the friction and wear when relative movement of the strands occurs and also acts as a anti-corrosion agent. i have no idea though how the influence of the lubricant can be quantified.

 

[BEMPE16524]

you should get something from here: Link
please see section: [highlight #F57900]SECTION 3 MACHINERY AND EQUIPMENT[/highlight]

this too: Link

See the attachment also.
R.Efendy

 

[btrueblood]

To add to a list of useful documents,

Google "uss wire rope engineering handbook" - older stuff, but much useful info. there, multiple sources.

Also the "US Navy Wire Rope Handbook", vols. 1 and 2 (there's a vol. 3 that covers operations and maintenance as well)
Vol 1:

https://apps.dtic.mil/dtic/tr/fulltext/u2/a955305.pdf

and Vol. 2:

https://ntrl.ntis.gov/NTRL/dashboard/searchResults/titleDetail/ADA955309.xhtml

 

[BEMPE16524]

Vol 1:

https://apps.dtic.mil/dtic/tr/fulltext/u2/a955305....

the link is dead

R.Efendy

 

[3DDave]

It's seems like DTIC servers are currently off line.

And now they are back.

 

[Ivan Silva]

Thank you all of you, sirs. I could download the three of us navy wire rope handbook. I’lol upload it to my google drive then I’ll share a link for those who couldn’t download it.

 

[Ivan Silva]

Volume 1Link

Volume 2
Link

Volume 3
Link

 

[Ivan Silva]

Tiger Brands Wire rope engineering handbook Link