Advancements in the Field of Wire Rope Design and Manufacturing

The current specifications governing the construction of wire rope and the fabrication of the assemblies used in movable bridges are no longer the best or most reasonable choice for wire rope selection. The current AASHTO and AREMA specifications for wire rope list “6x19 class improved plow steel wire rope of 6x25 filler wire construction with hard fiber core” as the construction for both operating and counterweight ropes. This paper describes the developments made in the design and manufacturing of wire rope since these specifications were written. Numerous wire rope constructions are available now that outperform the above mentioned construction in fatigue cycle testing as well as producing higher minimum breaking forces for a given rope diameter. Some of the developments include the ability to produce higher strength drawn-galvanized wires, compacted strands, corrosion inhibitive lubricants, and low torque wire ropes. This paper compares the reverse bending fatigue life cycles of the 6x25 filler wire rope construction with a fiber core to various constructions of ropes with a focus on the importance of an independent wire rope core ( IWRC ) center in the construction of any wire rope.