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Up Topic Welding Industry / Technical Discussions / Attaching an end onto a 5T hoist cable
- - By jwright650 (*****) Date 02-13-2006 18:29
What is the proper way to attach the end onto a hoist cable for our over head cranes? My maintenance guys have been doing it like this:

>Saw off a 3/4" length of 3/4" round bar.
> drill a 5/16" hole centered through the center of the round bar for the entire 3/4" length.
>slip the 5/16" 6/19 steel cable through the hole in the rd. bar.(cable bought in bulk on large spool)
>use a Oxy/fuel torch to heat the rd. bar until bright red.
>braze the end onto the cable.
>reattach to the drum of the crane hoist.


http://img.photobucket.com/albums/v345/jwright650/welding%20pictures/Cableend.jpg

I'm not crazy about applying this much heat to a cable like these guys are doing. Anyone know the proper way to recable one of these hoist? All I hear when I asked about this method of attaching an end onto the cable is that we have been doing it like this for years without incident. I just don't want to see the first incident. Opinions?
Parent - By aevald (*****) Date 02-13-2006 19:18
Hello jwright650, is there any way that you can swage an end piece onto the end of the cable using a mechanical method? Most of the rigging companies in my area have the proper machines to accomplish this. Generally the reason for applying this type of end on the cable is to prevent it from unravelling, the deadhead on the drum should not rely on this end for anchoring it. I would venture to guess that your maintenance people are using the logic that they aren't relying on this end for actual support of any load and thus the heat affected portion of the cable isn't subjected to loading and they feel that it is safe. My position would follow your train of thought though and I would feel better with a method that did not involve this heating. Hope this helps, aevald
Parent - - By bmaas1 (***) Date 02-14-2006 01:56
John

Personally I would not screw with what you are messing with. Cranes are an animal by themselves. You will now take on the responsibility of the crane rather that the mnufacurer.
Good luck,

Brian
Parent - By MBlaha (***) Date 02-14-2006 05:24
Many years ago, I went to cut the end of a 1" cable that was spooled onto the drum of a crane with a cutting torch. The operator came out of his cab yelling at me at the top of his lungs. (they could do that to us youngsters back them LOL). When he got done yelling, I asked him to please explain what was wrong with using a torch. He explained to me that the strands of the cable have to be able to work. Running the cable through sheeves and blocks, the cable is constantly twisting. Any time you braze, or even melt the cable, you are locking the strands together and thus, preventing them from working independently. That is why they manufacture cable cutters which shear the end of the cable off with. I would suggest strongly that you contact the crane manufacturer and follow his specifications to the tee as to how to connect the cabel end to the drum. Usually, a wedge that is groved to the size of the cable, shaped kinda like a pear or teardrop is used. You simply make an eye, put the swedge in the center of the eye, and then tighten the cable by applying tension to the cable.

Mike
Parent - By jwright650 (*****) Date 02-14-2006 13:37
One of my maintenance guys came to me and asked me for the proper technique and I didn't readily have an answer, but I was fairly certain applying heat wasn't a good idea. We have had several guys in maintenance in the 21 years that I've been with this company and hundreds of cables have been changed in this time frame using the method I described earlier. I'm going to try to get in touch with the hoist mfg and see what their recommended method is for recabling these hoists. We are in the process of taking out the old METEOR hoists because we can't get parts for them any longer and the drums are worn terribly bad and will damage a brand new cable in less than a week.
I'll post back when I hear from them.
Thanks for all the replies and emails concerning this. The safety of our guys is most important.
John Wright
Parent - By billvanderhoof (****) Date 02-14-2006 08:02
It seems that the termination you are building is called a "button". By far the usual method for attachment seems to be swaging. However here- http://catalog.thecrosbygroup.com/body_032.htm
you will find a spelter button. Spelter is zinc and can be used to attach terminal devices to cable (here they are recommending some sort of resin filler but same idea). Unfortunately the sizes only go down to 1/2 inch but it's a place to start. It is said that this type of termination, properly made, will develop the full strength of the cable.

googled for "wire rope" spelter button

Bill
Parent - - By Dave (**) Date 02-15-2006 16:28
You may also wish to check safety standards, both federal and state. In Michigan they are available online at: http://www.michigan.gov/mioshastandards Your state most likely has something similar. "Part 18" covers overhead cranes and "R 408.11824 Wire rope" gives some insight on maintenance and end fittings of wire rope.

Dave
Parent - - By johnhanging Date 03-09-2006 21:30
Typically several wraps of rope must be left on the hoist drum at the ropes lowest point of travel. By doing so the load at the anchorage is minimalized regardless of the hoist load due to the friction between the wrapped rope and the drum. Twisting should be minimal on a drum hoist also. All the same you're better off swaging a fitting to the end than brazing or welding rope, since either process will cause embrittlement.
Parent - - By jwright650 (*****) Date 03-09-2006 21:39
Thanks for your reply,
I've been looking into a set of dies to swage the steel fittings onto the wire rope to make up the end. Portability is the next obstacle to overcome because the press required is very heavy, and I need to be able to get the swager within reach of each overhead crane. If you try to install the button on the cable ahead of stringing the cables through the pullies, you can't get the button through each pulley system. So it has to be done after reaving and just before rewinding the drum. Like you said, we leave about 5 wraps on the drum after the hook hits the floor. I'm still sorting out our options, so we can quit the brazing on those ends.
John Wright
Parent - - By webbcity (***) Date 03-10-2006 17:27
john , this is my most interesting post so far (it made me log in and get more involved ) i didn't look closely at the picture and see the size of cable . some info. that i sent was to big . if you want i can send a page that has fittings that are close to the size you require . they are not farrules they are stops . there are small presses that are portable . if this goes on drum end what what type fitting on other end ? is drum smooth or lagged ? how many parts in line in reaving ? i will continue to check till we help you solve this . keep up the good work . willie
Parent - - By jwright650 (*****) Date 03-10-2006 17:35
Willie,
Here is what i was looking at...

http://catalog.thecrosbygroup.com/body_040.htm
and
http://www.strider-resource.com/ops350.html
John Wright


edit: We use a 5/16" 6x19 lay wire rope on the 5 ton cranes.
Parent - By webbcity (***) Date 03-10-2006 17:58
john , i just sent you a page . hope it helps . they don't have a press listed that is the size you need . but i know there are others that are out there that should work for that size , and are not so heavy should not cost as much . you might be able to use one from a power line contractor they use small presses and some have dies to fit your needs . there are lots of these type presses in use . will stay in touch . willie
Up Topic Welding Industry / Technical Discussions / Attaching an end onto a 5T hoist cable

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