×
INTELLIGENT WORK FORUMS
FOR ENGINEERING PROFESSIONALS

Log In

Come Join Us!

Are you an
Engineering professional?
Join Eng-Tips Forums!
  • Talk With Other Members
  • Be Notified Of Responses
    To Your Posts
  • Keyword Search
  • One-Click Access To Your
    Favorite Forums
  • Automated Signatures
    On Your Posts
  • Best Of All, It's Free!
  • Students Click Here

*Eng-Tips's functionality depends on members receiving e-mail. By joining you are opting in to receive e-mail.

Posting Guidelines

Promoting, selling, recruiting, coursework and thesis posting is forbidden.

Students Click Here

Jobs

wire rope and zinc-poured sockets...
2

wire rope and zinc-poured sockets...

wire rope and zinc-poured sockets...

(OP)
Oh, the projects I get myself into...

In my research on how zinc-poured sockets "work" pertaining to wire rope, I've found API 9B "Recommended Practice on Application Care, and use of Wire Rope for Oil Field Service" and the very interesting American Rigger's Supply, Inc. catalog. I also have my old Handbook of Ocean and Underwater Engineering. At home I have a neat book on cable structures - but I'm not at home right now...

Anyway, the API almost gets me what I want: just how strong is a zinc-poured socket? The American Rigger's Supply catalog, however, has load ratings. For example, a zinc (or resin - ?) poured socket used with a wire rope diameter of 2.5 inches have a rated capacity of 52 tons = 104 kips. The length of the Improved Plow Steel (IPS) socket that's in contact with the poured zinc is 9.75 inches (open or closed socket, the length is the same).

How am I to interpret this? I am assuming that the zinc poured is of ASTM B6 grade 1 (from the API 9B...). I'd like to say that there's a direct relationship between the length of the socket in contact with the zinc and the socket's length. For example, my 2-1/2 inch diameter wire rope zinc-poured socket has a strength per inch of length of 104 kips/9.75 inches = 10.67 kips/inch. If I could justify that, my day would end in triumph.

Any assistance is most appriciated! Thanks to all in advance!

refs: http://americanriggers.thomasnet.com/item/wire-rope-slings-sockets-zinc-or-resin-poured/poured-sockets/ps-062?&seo=110.
http://wwwrcamnl.wr.usgs.gov/sws/cableways/descr.htm
http://www.dsiamerica.com/products/Multistrand_Couplers.html - eh, not really what I was looking for, but it helped a little.

RE: wire rope and zinc-poured sockets...

Erg.  I see the data on the american riggers site, Dave, but my Machinery's Handbook lists wire rope breaking strengths of well over 200 tons for 2.5 inch rope diameters, so a breaking strength of 52 tons seems awful low (especially when Machinery's Handbook and the Am Riggers website both suggest joint efficiencies of 100% for poured sockets).

RE: wire rope and zinc-poured sockets...

(OP)
Well, then, I've got to get myself a copy of the Machinery's Handbook!

If there's 1005 effciency, I'm happy! Thanks!

RE: wire rope and zinc-poured sockets...

Rated capacity and breaking strength are not the same thing.

RE: wire rope and zinc-poured sockets...

(OP)
OK... then what kind of info is out there on the bond or adhesive strength between zinc and another metal?

RE: wire rope and zinc-poured sockets...

See page D-10 in
http://www.usbr.gov/ssle/safety/RSHS/AppD.pdf

Also this
http://www.usace.army.mil/publications/eng-manuals/em1110-2-3200/c-3.pdf

Every manual lists the "spelted" or poured socket as the fitting used to measure breaking strength of wire rope, thus these fittings must reliably be able to attain 100% of the rope's strength.  

Publishing a "rated load" for wire rope and fittings is somewhat criminal.  Dave, I'd suggest you buy a fitting from somebody else.  Breaking strength is a no-bull**** rating.  Users of wire rope and fittings should apply the appropriate safety factors for their particular situation (static vs. running loads, human life/safety, etc.).

RE: wire rope and zinc-poured sockets...

(OP)
Excellent! Thanks again!

RE: wire rope and zinc-poured sockets...

I am with btrueblood here, every socket I have seen or worked with has always been rated at 100% of the rope/strand strength. They are designed that way!
Usually, for suspenders on bridges you also do a destruction test with a sample socketed at both ends. The test is considered as passed when the assembly achieves the 100% capacity of the rope.

Red Flag This Post

Please let us know here why this post is inappropriate. Reasons such as off-topic, duplicates, flames, illegal, vulgar, or students posting their homework.

Red Flag Submitted

Thank you for helping keep Eng-Tips Forums free from inappropriate posts.
The Eng-Tips staff will check this out and take appropriate action.

Reply To This Thread

Posting in the Eng-Tips forums is a member-only feature.

Click Here to join Eng-Tips and talk with other members!


Resources