Wire Ropes, Elements and Definitions - Wire Ropes: Tension, Endurance, Reliability - page 26

Fig. 1.24 Warrington-Seale

strand

(symbol WS)

Fig. 1.25 Compound lay

strand

(symbol N)

The Filler strand was invented by the American James Stone in 1889. The Seale
strand is named after the inventor Seale (1885). The inventor of the Warrington
strand is unknown. The strand presumably gets its name from the British town of
Warrington, Verreet ( 1988 , 1989 ).
Parallel lay strands with three—they are rarely found with more—layers are
also laid in one operation. Once again, the wires of all layers have the same lay
length. Of all parallel lay strands with three layers, the one used most is the
Warrington-Seale strand. The Warrington-Seale strand consists of a central War-
rington strand construction and an outside Seale wire layer.
Warrington-Seale

ropes mostly have 1 + 7 + (7 + 7) + 14 = 36 wires

(36WS) as shown in Fig. 1.24 .
Compound lay strands. Compound strands (symbol N) contain a minimum of
three layers of wires where a minimum of one layer is laid in a separate operation,
but in the same direction, over a parallel lay construction forming the inner layers.
In Fig. 1.25 , a Warrington compound strand with 35 wires (35WN) is shown as an
example.

1.2.2 Shaped Strands

Strands which are not round are called shaped strands, Fig. 1.26 . The triangular
strand (symbol V) has a perpendicular cross-section which is approximately the
shape of a triangle. The oval strand (symbol Q) has a perpendicular cross-section