[TowerTalk] Preformed Guy Grips

[Tom Rauch]

> I had occasion this week to closely observe the power company reworking my
> electric and installing some new power poles for our new house. I looked
> closely at their cable and their grips.
> 
> I noticed that their guying cable has a right-hand twist. I then looked at
> their PLP grips (yes, they were made by PLP) to verify that they also had
> a right-hand twist.

That's because they were using aluminum clad steel wire, and 
grips designed for that wire, instead of guy strand.

Power line conductors, like ACSR cable, are intentionally 
manufactured in a right-hand lay (as are the matching grips) to 
avoid any mix-up between support strand and the very much 
weaker aluminum clad conductors used for power lines.     
 
> This is directly opposite to Rohn 1/4 inch EHS  cable that has a left-hand
> twist and the PLP grips (BG-2144) that also has a left-hand twist to
> match.

That's because all-steel cables are standardized in a left-hand lay. 

> I don't know whether all power companies use right-hand twist cable, but
> you need to be aware that all cable isn't made the same. You should never
> mix grips and cable that don't have the same twist.

Bottom line is you should never use stranded copper, aluminum, or 
aluminum clad steel as guying material. If you avoid that very big 
error, and obtain the correct EHS hardware, you'll never have a 
problem.

Virtually all of the tower failures I've seen have been from gross 
mistakes. Guy-clamps on backwards (saddle on flying end instead 
of load bearing end)...trees falling on guylines...undersized 
anchors...guy lines or guy grips without a thimble bent over sharp 
or small radius points (like the common practice of putting a guy 
line or grip around the leg but over the small crossrail of a Rohn 
tower where it lays against the inside of a leg).


73, Tom W8JI
w8ji@contesting.com

--
FAQ on WWW:               http://www.contesting.com/FAQ/towertalk
Submissions:              towertalk@contesting.com
Administrative requests:  towertalk-REQUEST@contesting.com
Problems:                 owner-towertalk@contesting.com