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Elevators and Their Cables Forever

                    Change Urban Architecture

                                                 by Peter Hildebrandt

         In 1857, at around the same time that John Roebling began to explore uses for his newly-
         developed wire rope cables, the Haughwout and Company department store opened
         its doors on Broome and Broadway in Manhattan. The structure housing this company
         – including its groundbreaking facade, crafted from cast-iron – remains standing to this
         day. On March 17th of that same year, the building’s owner announced in the New York
         Times that, “The elegant and varied assortment of new goods with which we shall open
                                            has probably never been equalled in this country.” However,
                                            what the Times article neglected to mention was the fact
                                            that Mr. Elisha Otis had installed the country’s first passenger
                                            elevator carrying people up to the structure’s different floors.

                                                 hough more often than not Otis   less paralleled the invention of the pas-
                                                 is the one attributed as the eleva-  senger elevator, and, by the 1870s, wire
                                            Ttor’s inventor, his patent was on   rope had become the rope of choice for
                                            the safety device that had it’s first use   elevator use. Due to their relative new-
                                            at Haughwout’s store. Early elevators   ness,  both the elevator and wire rope
                                            – the same as in portage railway days –   faced similar challenges with regard to
                                            had hemp ropes pulling them up.    safety concerns. The older hemp hoist-
                                              Soon though, Otis and Roebling’s work   ing rope had a long history of use, and
                                            would come together. John Roebling’s   its strengths and weaknesses were well
                                            son  Washington  recalled  that  early  on   known. However, a rope made of wire
                                            some  in  the  wire  rope  business  viewed   was an entirely different matter.
                                            elevator ropes as a nuisance, adding, “yet   This difference was effectively sum-
                                            forty years later we are making millions   marized in  the  June 22,  1878 issue  of
                                            upon millions of feet per annum and   American Architect and Building News,
                                            their manufacturing comprises nearly   which included a brief article on elevator
                                            one half of all our business – all begin-  ropes. The article expressed the prima-
                                            nings are difficult, but don’t give up.”  ry concern as being, the sudden intro-
                                              The humble hoisting rope occupies a   duction in our large cities of elevators,
                                            unique place in the history of vertical   most of which are hung by wire ropes,
                                            transportation. A simple hemp rope lies   has led people to wonder what will hap-
                                            at the center of one of the best-known   pen when they have had a year’s wear,
                                            elevator stories — Elisha Graves Otis’   and why there should not, after a while,
                                            demonstration  of  his  Improved  Safety   be a breaking of ropes, and consequent
                                            Device  at  the  1854  Crystal  Palace  in   accidents all over the country.
                                            New York City, just a bit before Haugh-  The key concern centered on the en-
                                            wout and Company opened their store. A   durance of wire rope and its reaction
                                            sophisticated carbon nanotube “rope” is   to constant and repeated  bending as
                                            the primary innovation driving the con-  it  passed around  winding  drums  and
                                            ceptual – and possibly literal – develop-  over sheaves. One of the same article’s
                                            ment of the proposed space elevator.   key assumptions was that “everybody
                                              However, it remains the wire rope   knows,  at least, that reiterated bend-
                                            that retains pride-of-place in eleva-  ing  weakens  wire,  whether  it  be by
                                            tor history as the longest-serving sus-  granulation or by the constant exten-
                                            pension means. It was the subject of   sion of its fibers.” The challenge was, in
                                            numerous  19th-century  articles  that   spite of “knowing” that this action oc-
                                            questioned its safety, and it has been   curred, there was no easy way to judge
         Construction site  of the  246  meter  high   featured in countless contemporary   when a rope was no longer safe for use.
         Thyssen Krupp Elevator Test Tower in Rottweil,   books, movies and TV programs that   John A. Roebling’s Sons Company, as
         Germany in 2016 (finished in 2017). It is now
         used for testing  and certifying innovations   predicate  disaster  on  its  failure.  The   the article claimed, had recently  pro-
         in elevator technology using 12  test shafts   history of the elevator must also include   vided good advice regarding the use of
         and travel speeds  of up  to 18  meters per   the introduction of wire elevator ropes   wire  rope,  stating that “large drums,
         second. Having the highest visitor platform   in the 19th century and their matura-  sheaves and pulleys are absolutely nec-
         in Germany, it’s the world’s tallest tower built
         to test elevators worldwide.       tion in the first half of the 20th century.  essary for the long life of a wire rope.”
         Photo © Frank Gärtner |  The invention of wire rope more-or-            continued on page 26
         24     Wire Rope News & Sling Technology   February 2018
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