I am reviewing the engineering calculations for a Triex LM 354 tower, a
paper copy of which is signed and sealed by a Civll Engineer. The 19 page
doc, gives the uninitiated a small, insight into the calculations, including
the mathematical equations used, for all aspects of mechanical engineering
of that particular tower. One calcualation, that of loads on, and thus
tensile strength requirements of, the lift cable, I am examining for insight
to viability of stainless steel lift cable substitute for galvanized steel
iin hopes of eliminating worries of deterioration due to corrosion.
The LIFT CABLE STRESS Calcs:
(Quote)
1/4 x 7 x 19 galv aircraft cable
Maximum Breaking Strenght = 7000 lbs
Factor of Safety = 7000/540 = 13.0 >3.0
(Unquote)
(where 540 is a calculated value of tension on the bottom run of the cable.)
If I interpret this line correctly, is it saying:
Factor of Safety is 13.0 which is much greater than a minimum factor of
safety of 3, therefore easily passes.
Is this an good interpretation of what the Engineer writes?
If so, then stainless steel lift cable, which according to most wire tables,
has only slightly less tensile stregth than similar galvanized steel cable,
should also easily meet requirements for lift cable for ham towers..
Or am I, as an unprofessional observer missing or assuming too much?
Tnx...
73, DX, de Pat Barthelow AA6EG aa6eg@hotmail.com
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