8x21 F
Eight strands, each in Filler construction 1-5-5F-10
FC
NFC
SFC
Fiber core
Natural fiber core (sisal) Used only for rope diameters above 8 mm (5/16").
Synthetic fiber core (polypropylene). Used for rope diameters 8 mm (5/16") and below.
U
Uncoated (bright)
1370/1770 (traction)
1570/1770 (extra high strength)
680/1270 (iron)
Dual tensile, outer wires: 1370 N/mm², inner wires 1770 N/mm².
Dual tensile, outer wires: 1570 N/mm², inner wires 1770 N/mm² .
Dual tensile, outer wires: 680 N/mm², inner wires 1270 N/mm² .
sZ
zZ
Right ordinary lay (Right regular lay)
Right Lang lay
8 to 22 mm (5/16" to 7/8").
Properties & applications:
Elevator rope. This construction is slightly more flexible than the traditional 8x19S so it has better fatigue resistance but it is slightly less resistant to abrasion. It is becoming more and more common as hoist rope on traction drive elevators.Information for use and maintenance:
Rope Category Number (RCN): 05 Rope ends must be secured against rotation.