Broken aluminum ring

  • Thread starter Tobe Sherrill
  • Start date
  • Replies 205
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I bought a couple aluminum rings such as these a couple years ago to make a friction saver and was amazed at how much softer they were than my aluminum carabiners. I don't know much about metal, but they obviously were treated differently or were of different stock or something. The aluminum rings scratched so easily and abraded alarmingly just from rubbing against each other in a ring and ring FC. None of my carabiners are so prone to scratching/abrasion. I quickly replaced those rings with steel ones.

That being said, I agree with Brian. Gear inspections is crucial.
 
I'm hardly an expert, but choosing steel over aluminum due to safety concerns, would seem to be a false motivation, if you accept the fact that aluminum life support mechanisms are properly designed, which I think that you generally can, when choosing products from reputable manufacturers.

Engineers use very different failure criteria for evaluating steel compared to aluminum. When aluminum is designed to the same overall standards as steel, it may actually be stronger. Aluminum is designed to the point of "flexure", when considering failure. Steel is designed to "yield point". Designing with consideration to "flexure", with aluminum, can provide a higher tensile and yield compared to a basically equivalent steel component. It's somewhat like comparing apples to oranges.

There are other factors involved too, like corrosion, but the bottom line main factor, is given proper engineering, and using the device within the weight restrictions, there is no added risk for aluminum.
 
Sophia, one of the owners of New Tribe climbing gear told me they stopped using the anodized alum. rings because over time they had a ring with a small area of anodizing rub off. The edges of the anodizing made a sharp cutting surface which abraded a climbers rope
 
The polished aluminum rings I had on my friction saver were so abraded after just a few climbs that I started taking sandpaper to them after every use for fear that they would start tearing rope fibers. At that point I realized I had to go with steel. Finding steel rings was no easy task, though. Many thanks to Rich Hoffman at the Buzz for hooking me up with some nice steel rings.
 
  • Thread Starter Thread Starter
  • #30
Latest --

We’ve just completed a test to failure of nine small Kong rings and none broke below 6,800 pounds.

Since the broken ring in this incident lacks identification or a rating stamp we are inclined to direct our attention there. In inventory we discovered one Kong box of small rings with no markings (brand or ratings) as we’ve insisted upon from Kong on life safety products. This box was among other Kong boxes of rings that have the marks. Kong is looking into why they shipped unmarked rings (only small as far as we can tell).

NOTE; Kong is not the only manufacturer of aluminum rings for life safety that do not have a printed stamp of brand and strength.

Half of the failed ring has arrived here from the principal in the incident and will be forwarded to an independent lab, followed by the manufacturer in Italy for examination(s).

In the mean time we have pulled from inventory any unmarked rings (including spliced goods containing such) and await the manufacturers response.

Unless the outcome points to lack of concern for quality or outsourcing to an unmonitored manufacturing facility then I’ll retain great respect and trust in Kong products. This company is well respected around the world for a high standard of safety in climbing, paragliding and rescue disciplines, to name but a few. From all that I know and from years of working with their people I will continue to trust my own life to their products.

More as it’s received.

Tobe
 
Thanks again, Tobe.

I have two friction savers with aluminum rings, but they both use hard coating. Made by Buckingham. They wear really well, so far. I don't think I like the idea of aluminum w/o hard coating.

I cut through the hard coat on a CMI rescue 8 years ago, rappelling on gritty rope...that went straight to the trash can, as the bare aluminum wore really fast, once the hard coat was breached.
 
For those of you who haven't had the opportunity to meet Rich in person-he is a super nice guy. He has posted here a little in the past but I think that he doesn't hang out here too much partly because Nick is our splicing king and since spliced gear is a big part of Rich's livlihood I don't think he wants to "horn in " and compete with Nick.
 
  • Thread Starter Thread Starter
  • #35
Hold up there guys, let’s not throw the baby out with the bath water over this issue. Not that the issue isn’t significant because it is. Suppliers will likely take this as a shot across the bow regarding quality assurances. SherrillTree certainly has.

The vast majority of aluminum life safety hardware is sound, reliable and extremely tough. Think about this;

During 25-years of serving this industry I’ve never seen an aluminum carabiner snap in two…ever. I’ve seen them straightened, I’ve seen the gates blown out and I’ve even seen rope abrasion that’s alarmingly deep, but never broken in two as witnessed with this cast ring. Damaged gates are most always due to misloading directly upon the gate while abrasion is easy to detect and provides the user plenty of indication to retire. And insofar as straightened carabiners go, all have been due to loads that were crazy high. Think about it, has anyone ever heard of the weight of a human being (except perhaps Sylvester Stallone in Cliffhanger) breaking a carabiner? I haven’t. And again the failures I’ve seen were reported by living users admitting abuse. (BTW -most of the same failures have been witnessed with steel too)

With that in mind also know that we sell perhaps 100-times more carabiners than these friction saver rings, and I would venture to guess that the carabiner gets used more in a week that the ring in a month.

This is a strange bird for sure.
 
I broke a Petzel pear shaped biner.

Granted I had my 9klb Warn winch stalled against it several times before it blew.
 
Sounds like Carl picked up the girl from the "other thread".



:lol:
 
  • Thread Starter Thread Starter
  • #42
Dear friends,

Attached to this post is official notice from SherrillTree recalling an aluminum ring sold for use in life support activities.

Certified notice by US mail along with return packaging is being assembled for distribution in the coming few days.

The rings that Sherrill, Inc. distributes have always been strictly sourced from KONG Bonaiti of Italy based on a high level of confidence in products forged by the manufacturer. It appears that the rings in question were not and, most importantly, did not receive individual testing.

We strongly recommend climbers using polished aluminum rings not sourced from SherrillTree (or Vermeer dealers) and not having strength ratings inscribed, to contact their supplier and push for replacement. There’s great likelyhood that the manufacturer of the ring in question (not Kong) exports directly or indirectly to several other arborist suppliers.

(Known arborist manufacturers NOT distributing this ring include Petzl, Buckingham and Komet.)

With best regards,

Tobe Sherrill
 

Attachments

  • NoticeLetterV2.pdf
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Right here. All our rings have the strength in kN printed right on the side. We don't sell the kind without the inscription.
 
Tobe, can you please clarify which of the Sherrill products may have used the rings in question? I have purchased a lot of your goods for people here, and without my informing them of the recall, they will not get the word.

Thanks.
 
Were the rings sold individually? I bought a small aluminum ring with no markings at the Vermeer store in Greensboro... it's my bridge tie-in. Should I ditch it?
 
Bounce said:
Right here. All our rings have the strength in kN printed right on the side. We don't sell the kind without the inscription.
Click to expand...

I'll check again, but I didn't find any markings.

They were def. purchased from you guys also.

I can actually remember buying them, as it's the first time I spoke with you when ordering. They were back ordered at that point. I can pull the receipt.
 
Just looked at them, along with finding recepit.

I have two unused no markings. One on my FC no markings.

Purchased 1/3/2008.

Item # KNG28A, New # CL1902

Transaction # CS-39488

The two large I have have markings.
 
What ar the dates for recall tobe....I have quite a few unmarked rings.
 
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