Cable Sag
Cable Sag
(OP)
Hi
I'm looking to calculate the sag of a flight control cable under it's own weight (zero tension). The cable is in steel, 5/32" diameter. Does anybody knows the formula to calculate the sag?
Thanks,
Chopin
I'm looking to calculate the sag of a flight control cable under it's own weight (zero tension). The cable is in steel, 5/32" diameter. Does anybody knows the formula to calculate the sag?
Thanks,
Chopin





RE: Cable Sag
RE: Cable Sag
y = a cosh(x/a).
Now how do I determine "a"?
Thanks,
Chopin
RE: Cable Sag
RE: Cable Sag
http://mysite.du.edu/~jcalvert/math/catenary.htm
or this ...
http://spaceagecontrol.com/calccabl.htm
RE: Cable Sag
Try looking for an old guy where you work, and ask to see his mechanical reference books.
RE: Cable Sag
H = wl^2 / 8d
l = span
H = tension at mid-span
w = load in plf or klf - keep track of units
d= sag
As you can see - the more sag - the less the load and vice versa.
You will NEVER get all the sag out - so make some guess - like 1'' or 2'' or whatever
RE: Cable Sag
w = 0.005 lbs/in
L = 100"
H = 200 lbs
d = 0.005*100^2/(8*200) = 0.03"
RE: Cable Sag
Check your units - I think you might have a problem
RE: Cable Sag
w is weight (lbf) per in run
L is in of run
H is tension in lbf
(lbf/in)*in^2/lbf = in to me ??
RE: Cable Sag
These old eyes and Walgreen glasses sometimes just don't work as good as they used to!!