Wire Ropes, Elements and Definitions - Wire Ropes: Tension, Endurance, Reliability - page 28

Introduced in Eq. ( 1.4a ) the compacting grade is

C ¼ 1 W S d S ; comp
m S ; comp

: ð 1 : 4b Þ

Strand Mass Factor. The strand mass factor W S can be evaluated by measure-
ments or calculated with the ratio of the effective strand cross-section A s,e mul-
tiplied by the wire mass density q and divided by the square of the strand diameter
d S,m

4 X

n

W S ¼ A S ; e q
d S ; m

q
d S ; m

p z i d i = cos a i : ¼

i ¼ 0

With small deviation the length-related strand mass factor is

W S ¼ 0 : 00485 kg/(mm 2 m)

for Filler strand 19 þ 6F wires

W S ¼ 0 : 00475 kg/mm 2 m for Seale strand 19 wires

W S ¼ 0 : 00483 kg/mm 2 m

for Warrington strand 19 wires

W S ¼ 0 : 00485 kg/mm 2 m for Warr.-Seale strand 36 wires

Example 1.1 Compacting grade

Data:

For a Filler rope 6 9 (19 + 6F) piece of the length L = 400 mm is
the mass of one strand piece M s,comp = 121 g
the strand diameter d S,comp = 7.27 mm
the strand lay angle b comp = 18.6
Results:

strand length l S,comp = L/cosb comp = 422 mm
length-related strand mass m S ; comp ¼ M S ; comp
l S ; comp

¼ 121

422 ¼ 0 : 287 g/mm ¼ 0 : 287 kg/m

The compacting grade is according Eq. ( 1.4b )

C ¼ 1 W S d S ; comp
m S ; comp

¼ 1 0 : 00485 7 : 27 2
0 : 287

¼ 0 : 107 ! 10 : 7 % :