Wire Ropes Under Bending and Tensile Stresses - Wire Ropes: Tension, Endurance, Reliability - page 310

S 0 ¼ ð F þ W d 2 x Þ g :

While accelerating the cage from the lower station, the rope piece x = L -
DL to L winding onto the drum is stressed by the highest tensile force. However
the tensile force difference DS = S - S 0 for this rope piece is relatively small.
Therefore, this piece of the rope does not have the lowest endurance if the rope
mass ratio here is c C 0.865.
The wire rope piece most stressed while bent is situated above the cage and
above the decelerating rope zone x [ DL. The distance between the cage and the
zone of rope with the highest stresses is x = DL + l/2 and a = 0.

S ¼ 304,400 N

and the lower tensile force

S 0 ¼ 81,000 N :

The difference between the tensile forces is

DS ¼ S S 0 ¼ 223,400 N and DS = S ¼ 0 : 734 :

The force factor according to ( 3.69 )isf S5 = 2.057 and the equivalent force is
S equ = fs5 S = 626,000 N

Number of load trips:
For drum installations the number of load trips is T = Z. The 10 %-limit and
the mean number of load trips up to the rope discard (The small influence of the
endurance factor f N4 = 0.984 for the loss by the rope twist angle x = -278/100d
from Table 3.15 is considered) is

for rope l

for rope ll
T A10 = 83,600

T A ¼ 202 ; 000

s = T A ¼ 0 : 0655 kg/Hub

The rope mass investment for one trip is

Alternative:
For d = 65 mm
Rope l T A10 = 170,000 T Am = 408,000 s/T Am = 0.0380
Rope ll T A10 = 100,400 T Am = 243,000 s/T Am = 0.0638.