Kevlar in UTP cable

[eth_jones]

Does anybody know why there is a thin strip of Kevlar in UTP? There's also a lot in fibre optic cable too, and I don't really know what purpose it serves.

All I know is it gets in my way when I'm trying to crimp the cables lol

[Windows7ge]

Some Googling brought me to this. Makes sense.

Quote

Actually it's for pulling the outer shielding away from the inner wires. When you're punching down the cable you pull the fiber string down from the top of the cable and it makes a nice split in the outer shielding that allows you to pull the outer shielding down to cut it off without damaging the inner wires. 

 

[mariushm]

I doubt it's kevlar... it's often steel wire, sometimes it's tinned copper....

It's sometimes called as DRAIN WIRE and it's there for better grounding of the mess/foil that wraps the twisted pairs.

 

Some cables have a RIP CORD, which is typically made of nylon - this is what is used to strip the sleeve of the cable.

 

 

[W-L]

1 hour ago, eth_jones said:

Does anybody know why there is a thin strip of Kevlar in UTP? There's also a lot in fibre optic cable too, and I don't really know what purpose it serves.

All I know is it gets in my way when I'm trying to crimp the cables lol

Usually it’s just nylon fiber as said for stripping back the insulation, there is self supporting or aerial cable that can have an additional wire or high strength fiber that is used for spanning between buildings or poles. 
 

-Moved to Networking-

[trueCABLE]

Hello!  Ethernet cable manufacturer here.  That is not Kevlar.  What you are referring to is a nylon rip cord.  This is used to strip the cable jacket instead of concentric stripping (using a cable stripper).  The pull string is useful when you don't need perfect concentric strips like when terminating to a RJ45 plug.  Necessarily, this pull cord is strong as it has to be.  Personally, I never use them and always concentric strip but then you risk conductor nicking...but I know to check for it and how to adjust a strip tool.

 

< content removed >

 

That water block tape is TOUGH stuff.  It is not Kevlar, however.

Edited December 22, 2019 by LogicalDrm

[eth_jones]

Thanks everybody for your replies. I was studying for an exam using a video course on Udemy, and the instructor clearly says that it's Kevlar inside the cable. It didn't make a lot of sense to me and googling it didnt bring anything useful either, so I really appreciate your help!!!!