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continued from page 24
         They also suggested that “ropes on pas-
         senger elevators ought to be changed
         every two years.”
           Interestingly, John A. Roebling’s Sons
         claimed that “the best elevator build-
         ers,” while they understood the need
         for large drums and sheaves were often
         restricted in their use due to the space
         limitations of penthouses and mechani-
         cal rooms. This raises intriguing ques-
         tions about the conversations among
         architects, engineers and elevator build-
         ers over the integration of this new tech-
         nology into new and existing buildings.
           Questions about the safety and prop-
         er use of wire rope were constantly
         raised throughout the 1880s and 1890s
         and were, in part, finally answered by
         the development of a “standard” eleva-
         tor wire rope. Hazard Manufacturing
         Co. of Wilkes Barre, Pennsylvania, spe-
         cialized in the manufacture of wire rope
         and was one of a half-dozen American
         companies that made this new product.
           The September 15, 1896 issue of the
         Street Railway Review described the
         contents of the company’s new cata-
         log, which gave “special attention to. . .
         the manufacture of standard elevator   Artist rendering of Elisha Otis’ demonstration of his free-fall prevention mechanism  (pre-
         ropes.” The standard elevator rope was   cursor to the elevator), Crystal Palace, 1854.
         “composed of  six  strands,  19  wires  in   subjected to wear and contain 40% of   trated the widespread use of wire rope
         each strand, or 114 wires in the rope, the   the total strength of the rope. The cen-  and contained a wealth of information,
         several strands laid firmly about a hemp   ter wires form a reserve strength after   which was presented in a textbook for-
         center, which forms a cushion and gives   the outer wires are worn or broken.”  mat that featured 10 chapters, four ap-
         elasticity to the rope.” The rationale be-  By 1900, the use of wire rope was an   pendices, a glossary and an index.
         hind its design was described as follows:  accepted feature of the industrial land-  The history of wire ropes in the 1920s
           “Of the 19 wires in each strand, 12 are   scape, and the use of standard  eleva-  and 1930s encompassed the continued
         outer or wearing wires and contain 60%   tor wire rope was an equally accepted   development  of the traction elevator
         of the total strength of the rope; seven   aspect of elevator operation. American   and  the  writing  of  the  first  elevator
         are inner or pulling wires, are never   Steel  &  Wire  Co.’s  1913 catalog illus-  safety codes. This period also saw the
                                                                               publication of catalogs devoted to eleva-
                                                                               tor wire ropes. American Steel & Wire
                                                                               Co. produced such a catalog in Septem-
                                                                               ber 1930, which was revised and reis-
                                                                               sued in June 1932. The catalog’s cover
                                                                               featured a stylized car supported by six
                                                                               ropes that led upward into a 1930s set-
                                                                               back skyscraper. The back cover also
                                                                               included the car and rope image; how-
                                                                               ever, here, the building was replaced
                                                                               by the company’s Tiger trademark.
                                                                                 American Steel & Wire felt that “due
                                                                               to  the  increase  in  height  of  modern
                                                                               buildings and the consequent neces-
                                                                               sity  of  quick,  quiet,  safe  and  efficient
                                                                               service required for the transportation
                                                                               of  its  tenants  up  and  down,  elevator
                                                                               manufacturers have been compelled to
                                                                               design new machines having quick ac-
                                                                               celeration, high speed and smoothness
                                                                               of operation combined with safety. We,
                                                                               as wire rope manufacturers, have kept
                                                                               pace with these improvements in eleva-
         Motor and traction systems for cable borne elevators installed in a machine room typical in high
         rise office buildings. This is where most wire rope wear-and-tear takes place.  tor design and are producing elevator
         Photo © Steven Rivieccio |                                              continued on page 28
         26     Wire Rope News & Sling Technology   February 2018
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