Page 20 - Wire Rope News & Sling Technology

 

 

 

 

 

Page 20 - Wire Rope News & Sling Technology
P. 20

continued from page 18
         do to manufacture  better chains  was
         stymied by the same roadblock: if one
         link failed in service, all was lost. He
         became even more frustrated when he
         learned other people had worked on the
         problem for many years without get-
         ting anywhere. Having reached a con-
         clusion  his studies with conventional
         iron link chains were a waste of time
         and money, he chose to drop all of it.
           Very suddenly he turned in an en-
         tirely new direction. He wrote: “How-
         ever, It occurred to me subsequently,
         at the commencement of last year
         (1834) that iron wire might be plaited
         or twisted together to form a whim   A wire drawing bench as it was used in Albert’s time had a drawing plate die standing upright
         rope…”  Albert  was  not  the  first  per-  between the payoff and the pulling capstan
         son to experiment with mechanical
         combinations of wire, but as of 1834   surrounding the numerous and varied   sive hemp rope weighed only 842 kg
         no applications in the world required   wrought iron wire gauge systems being   but his careful calculations showed he
         long  lengths  of  iron  wire.  He  was   employed  in European and American   could  have  made  a  wire  rope  for  this
         confronting  hoisting  problems  in  his   wire mill commerce during the 1800s.  shaft with more than enough strength
         mineshafts  which  were  hundreds  of   Albert’s meticulous notes contain   but weighing only about 80 kg.
         meters deep, but the longest rings of   the key questions he posed to himself   Concentrating  his  reasoning  on  the
         cold drawn iron wire available to him   and the answers he recorded about the   answers  to Questions  5 and 6, he or-
         were only 35 meters or less.       manufacture  of wire  ropes to replace   dered two  rings  of  10 gauge  wire  on
           One of the first questions he had to   iron chains and hemp ropes. In Germa-  January 18, 1834 from which he made
         answer was how to go about splicing   ny, Q&A in this format for responses is   two short pieces of wire rope using 12
         short  pieces  of  iron  wire  end-to-end   called “telegram style”:  wires for each of them. One of the ex-
         to achieve  longer  lengths  of  strand.   Question 1 – Is this feasible?  perimental ropes he made  was 4 by
         He faced a similar question with the   Answer – Yes                   3 and one  was  3 by 4. Because  only
                                              Question 2 – What are the costs?  short lengths of wire could be obtained,
                                              Answer – ¼ the costs of hemp rope  the splicing of strands and wires and
                                              Question 3 – What is the comparable   the  flexibility  needed  for  the  existing
                                            weight?                            hoisting  equipment emphasized the
                                              Answer - 1/5 the weight of chain  answers to Questions 5 and 6 were of
                                              Question 4 – What is the comparable   paramount importance.
                                            strength?                            Albert made two crucial decisions re-
                                              Answer – Far more than we need   garding  Question  6.  To  join  the  short
         The 3-strand and 4-strand Albert ropes,   Question 5 – Is it flexible?  lengths of wire he wrote: “After many
         both made of 12 wires with no core and no
         center wires.                        Answer – Yes                     trials I found it best to unite them by
                                              Question 6 – Can I make attachments?  friction…” which  turned out to work
         splicing of strands. It was obvious the   Answer – Yes                quite well. The wires were twisted
         manufacture of wire whim ropes would    When posing Question 3 to himself,   around each other, and whenever one
         be more difficult than the existing tech-  he used as his basing points the hemp   wire  end approached they added one
         nique for making an iron chain longer   rope and the 1900 kg chain  that had   more wire which first served as a cen-
         by forging connections  of additional   been used in one of the mineshafts   ter wire of the strand around which the
         links one at a time.               known  as  Hzg. Georg  Wilhelm which   other wires were twisted for several
                                            was 361 meters deep. The more expen-  turns. Then the new wire was brought
         THE FIRST WIRE ROPES                                                                   continued on page 22
           To fabricate his successful wire ropes,
         Albert decided to use cold drawn iron
         wires with a diameter he called “König-
         shütte am Harz mit No. 12 bezeichnet
         wird”  which  could  be purchased  lo-
         cally in the Upper Harz. This  size of
         iron wire was approximately 3 mm in
         diameter. For  some reason  the 1837
         American translation of his report has
         stated the wire diameter he used was
         “.144 inches” (which  corresponds to
         3,667mm).  In retrospect, this seems   Many workers were needed to
         slightly larger than what we’d expect   produce a strand or a rope. The man
                                            on the left moved the closing point while the
         for that gauge number. Perhaps this is   ropemaker on the right twisted the rope or strand. Between them other helpers
         an indication of the general confusion   got the twist out of the remaining rope or strand length.
         20     Wire Rope News & Sling Technology   June 2018
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