Wire rope Q

"DrollTroll" (clip) I would have thought some exotic-type brazing or welding would be required

^^^^^^^^^^^^^^^^^^^^ Welding a stranded cable would be virtually impossible. Brazing or silver soldering, if done very carefully in a temperature controlled oven, might work. If done by me, with a torch, the filler metal doesn't properly wet all the strands, and the outer strands get so hot the strength is shot.
Swaging or "crimping," or whatever you want to call it, works because the length of the collar has made long enough to to match or exceed the strength of the cable itself.
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"Welding a stranded cable would be virtually impossible."
Really??? Tell that to the Navy Aviation Boatswain's Mates working on aircraft carriers who regularly weld cables together whenever it's time to replace the purchase cables of the Arrresting Gear engines. The new purchase cable end is welded to a smaller cable "pig tail" and the old cable end and then the old cable is pulled until all of the new cable length has replaced all of the old ones around the various sheaves and pulleys in the system. The weld job needs to be precise and strong or else the cable connection would get stuck somewhere in the system or would break causing hours and hours worth of corrective actions rendering the aircraft carrier virtually crippled.
| | "DrollTroll" (clip) I would have thought some exotic-type brazing or welding | would be required | > for reliable strength. (clip) | ^^^^^^^^^^^^^^^^^^^^ | Welding a stranded cable would be virtually impossible. Brazing or silver | soldering, if done very carefully in a temperature controlled oven, might | work. If done by me, with a torch, the filler metal doesn't properly wet | all the strands, and the outer strands get so hot the strength is shot. | | Swaging or "crimping," or whatever you want to call it, works because the | length of the collar has made long enough to to match or exceed the strength | of the cable itself. | |
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"P D Fritz" wrote: Really??? Tell that to the Navy Aviation Boatswain's Mates working on

^^^^^^^^^^^^^^^^^^^^^ Are you sure they are really *welding* the cables, or are you just using the term to mean "joining." Welding two cables end-to-end would require fusion of the individual strands. Why would they do something so difficult when there are easier ways?
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Yes, they were/are welding. They were/are not brazing or soldering. They use electric arc welders using 7018 stick electrodes!!! They do it because they find it to be the fastest, the easiest and the strongest way to accomplish the required job.
I was one of them.
| | "P D Fritz" wrote: Really??? Tell that to the Navy Aviation Boatswain's | Mates working on | > aircraft carriers who regularly weld cables together whenever it's time to | > replace the purchase cables of the Arrresting Gear engines. (clip) | ^^^^^^^^^^^^^^^^^^^^^ | Are you sure they are really *welding* the cables, or are you just using the | term to mean "joining." Welding two cables end-to-end would require fusion | of the individual strands. Why would they do something so difficult when | there are easier ways? | |
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I used to weld the old cable to the new when I was replacing the cables on masonry block boom trucks. I would first weld a knob on the end of each cable then weld the two ends together. Using the old cable to pull the new one through, I then used a cutoff wheel on a 4" grinder and cut the old cable off. It worked a lot better that brazing them together and I never had one break during the threading of the new cable. Steve
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"Up North" wrote: I used to weld the old cable to the new when I was replacing the cables on

^^^^^^^^^^^^^^^^^^^^^^ Okay, Steve, I concede. The technique you describe sounds like it would work. Is that the way you did it, PD Fritz? I apologize for being so skeptical. My mind was stuck on the idea that the individual strands had to be joined.
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On Fri, 10 Oct 2008 23:05:57 GMT, "Leo Lichtman"

It threw me for a minute, too. The trick on this weld job is that it doesn't have to be strong or flexible, since it isn't in normal service. It only has to hold the two ends together long enough to pull the old cable out and the new cable into the sheave system. Then the weld and the old cable gets cut off, and the new cable gets properly terminated in place.
When you think about it, that makes perfect sense.
--<< Bruce >>--
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| | "Up North" wrote: I used to weld the old cable to the new when I was | replacing the cables on | > masonry block boom trucks. I would first weld a knob on the end of each | > cable then weld the two ends together. Using the old cable to pull the new | > one through, I then used a cutoff wheel on a 4" grinder and cut the old | > cable off. It worked a lot better that brazing them together and I never | > had one break during the threading of the new cable. | > Steve | ^^^^^^^^^^^^^^^^^^^^^^ | Okay, Steve, I concede. The technique you describe sounds like it would | work. Is that the way you did it, PD Fritz? I apologize for being so | skeptical. My mind was stuck on the idea that the individual strands had to | be joined. |
No apology required. Sure, it does sound basically similar. The cables I'm talking about though are 1 7/16 inch in diameter with each single strand approximately around 1/10". The "pigtail cable" that is about 3/4" in diameter and 2 feet long is connected(welded) in between the new cable and the old cable to allow maximum flexibility and maneuverability during its passage through the various pulleys and fairlead sheaves in the system. Sometimes, even chain links are used as a pigtail instead of a cable. I prefer the chain link method myself.
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Dang. 1 7/16" stuff. I thought 1 1/8" derrick cable was big.
Steve
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Replacing 1 1/8" cable on an oil drilling rig was interesting. The cable came in very long rolls. The first time it was strung, it was a booger bear. But when the required amount was on the sheaves, blocks, and drums, the cable was just dogged off. Since the pulling point at the top of the derrick and the drill floor level remained the same, only the cable rigged up would travel.
Usage was computed in ton/miles. When that was reached, the cable was pulled/threaded through all the sheaves and blocks until new replaced old, then the old was cut and deadmanned. It was all hard dirty dangerous work, especially the first time. After that, there was a Chinese handcuff thing that would join the end of an old section to a new spool, so no need to take it all off. Still, though, at times, it was necessary to start from scratch.
Steve
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Leo Lichtman wrote:

They are probably welding the end of a new cable (on a reel) to the end of the used one--then they will pull out the old & reel in the new.
jerry
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DrollTroll wrote: Brazing/welding would anneal the wire and cause serious loss of tensile strength. JR Dweller in the cellar

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wrote:

Zinced endings: There are three types of zinced endings: A cone is formed from molten zinc poured into a mold in which a frayed rope end has been inserted; sometimes a ferrule is used as mold and stays on after pouring the zinc; or sockets are used instead of the ferrule. An open socket has ears to hold a pin and cotter. A closed socket has a loop or "bail." Both are heavy forgings and find widespread use.
All three zinced on endings need a good deal of preparation. The rope's end must be broomed out, cleaned with acid and straightened. Special endings: such as thimbles, clips, and clamps are quicker and easier to apply than a zinc socket, but efficiency is not as high as with other attachments. These are filed attachments and inspection is necessary during service to make sure the nuts on the clips remain tight and provide proper holding power. Clips are U-shaped bolts with a grooved base and nuts to tighten-these and other grooved devices fit around a rope to form loops, or to provide endings similar to zinced sockets. In some cases, special thimbles and bolted clamps are used instead of clips.
Mechanical endings: A mechanical splice consists of a loop in the end of a rope and a sleeve pressed on the rope at the base of the loop to hold the end of the strands in place
Swaged endings: Swaging is the cold-flowing, under pressure, of metal fittings into the rope body, between strand sand wires. This pressure, applied by press or by rotary swagers, elongates the fitting but forces its metal inward so that the bond becomes permanent and compact, yet as strong as the breaking strength of the rope.
DaveB
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IIRC, they are poured molten zinc, probably with some alloys. It is called a socket.
Steve
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