Possible SCC on Wastelands Hellfire

Let everyone know about any suspect/dodgy/misplaced bolts to be renewed or avoided.
Post Reply
SamH
Posts: 3
Joined: Wed Aug 27, 2014 5:36 pm

Possible SCC on Wastelands Hellfire

Post by SamH » Tue Sep 11, 2018 4:52 pm

Hi,

Looks like bolt nr 5 (might be 6) on Wastelands in Hellfire is showing some signs of stress corrosion cracking. How bad does this look? Is rebolting even allowed at Hellfire?

Cheers Samuel
20180819_130225.jpg
20180819_130225.jpg (83.06 KiB) Viewed 1441 times

mokganjetsi
Posts: 1658
Joined: Fri Dec 15, 2006 12:32 pm
Real Name: Willem Boshoff
Location: Cape Town

Re: Possible SCC on Wastelands Hellfire

Post by mokganjetsi » Wed Sep 12, 2018 9:57 am

yikes!!!
that needs URGENT attention.
I believe Greg Hart is the guy to speak to regarding re-bolting at Hellfire? Anybody has his contact details?

User avatar
XMod
Posts: 931
Joined: Tue Jun 26, 2007 9:38 pm
Real Name: Greg Hart

Re: Possible SCC on Wastelands Hellfire

Post by XMod » Wed Sep 12, 2018 9:59 am

This NOT stress crack corrosion which we have seen in some of the mechanical anchors. Glue-in anchors dont suffer stress as there is no tension in the bolt.

What you are seeing is a crack on the SURFACE of the steel which formed during the bending of steel when the anchor was originally made. These early glue-in anchors where made by bending steel rod and welding the join. The steel is extremely tough and was very difficult to bend which led to the outer surface of the bend stretching to the point where it started to open up on a few of the bolts. Whilst this crack can be a starting point for further corrosion I very much doubt that it has reached the stage where the bolt has been compromised. Maybe in another 100 years the corrosion will have reached that stage.

That said. it should be possible to organise an ARF mission at the crag with special permission. There are certain other mechanical lower-off anchors that should be replaced (they are placed badly) and a few routes that could definitely do with an extra bolt or two to make them safe to climb. There are a few bolted routes at the crag where a slip at the wrong place could lead to serious injury or even death so where easily possible it would be good to fix that. However please note that not all of the routes can be made safe by the addition of one or two bolts, in some cases making the route safe would require so many new bolts that they would become 'clip-ups' ruining the adventurous nature of the line, such routes will be left as is.

Hellfire is quite a 'wild and wooly' place and to preserve this atmosphere we will NOT be sanitising routes to ultra-safe status by placing loads of bolts. Know your craft before you go there, climb within your limits.

User avatar
XMod
Posts: 931
Joined: Tue Jun 26, 2007 9:38 pm
Real Name: Greg Hart

Re: Possible SCC on Wastelands Hellfire

Post by XMod » Wed Sep 12, 2018 10:00 am

mokganjetsi wrote:
Wed Sep 12, 2018 9:57 am
yikes!!!
that needs URGENT attention.
I believe Greg Hart is the guy to speak to regarding re-bolting at Hellfire? Anybody has his contact details?
No I'm pretty sure the bolt is still fine, there is still a lot of steel left intact and that crack has been there since the bolt was made (see above post).

User avatar
XMod
Posts: 931
Joined: Tue Jun 26, 2007 9:38 pm
Real Name: Greg Hart

Re: Possible SCC on Wastelands Hellfire

Post by XMod » Wed Sep 12, 2018 10:12 am

I will chat with Cormac and set the wheels in motion for an ARF meet out there, we have been threatening to get this together for some time so it's high time for some action! There is quite a bit of cleaning up to do out there and will require a decent size crew and several tools to accomplish in a day.

User avatar
tygereye
Posts: 237
Joined: Fri May 27, 2005 7:34 am
Real Name: Brenda Marx
Location: Stellenbosch

Re: Possible SCC on Wastelands Hellfire

Post by tygereye » Wed Sep 12, 2018 10:59 am

I will be keen to help, Greg!

mokganjetsi
Posts: 1658
Joined: Fri Dec 15, 2006 12:32 pm
Real Name: Willem Boshoff
Location: Cape Town

Re: Possible SCC on Wastelands Hellfire

Post by mokganjetsi » Wed Sep 12, 2018 11:51 am

shot thanks for the explanation Greg!

Also very keen to assist in a ARF + clean-up meet :thumleft:

SamH
Posts: 3
Joined: Wed Aug 27, 2014 5:36 pm

Re: Possible SCC on Wastelands Hellfire

Post by SamH » Wed Sep 12, 2018 12:05 pm

Thanks Greg!

I would also help if there is an ARF action at Hellfire.

User avatar
Justin
Posts: 3758
Joined: Sat Apr 30, 2005 8:31 am
Real Name: Justin Lawson
Location: Montagu
Contact:

Re: Possible SCC on Wastelands Hellfire

Post by Justin » Wed Sep 12, 2018 12:39 pm

Keen to help too
Climb ZA - Administrator
justin@climbing.co.za

User avatar
XMod
Posts: 931
Joined: Tue Jun 26, 2007 9:38 pm
Real Name: Greg Hart

Re: Possible SCC on Wastelands Hellfire

Post by XMod » Wed Sep 12, 2018 5:46 pm

Awesome guys! Cormac says ARF has quite a full schedule but will announce the meet on here and usual ARF FB page once it has been all arranged.

There is also a little bit of path building/engineering needed and of course the usual millions of Hakea bushes that need to be pulled out so the more people the merrier - there will be something for everyone to do - no experience necessary.

The more people that attend the less work for each and the more climbing we can do :wink: :)

User avatar
Justin
Posts: 3758
Joined: Sat Apr 30, 2005 8:31 am
Real Name: Justin Lawson
Location: Montagu
Contact:

Re: Possible SCC on Wastelands Hellfire

Post by Justin » Thu Sep 13, 2018 8:48 am

I forwarded this onto Alan Jarvis (member of the Safety Commission for the UIAA). Below is his response:
Alan Jarvis wrote: Rather don’t call it corrosion, but cracks.
Need more information and a proper look to really tell but i’d bet that it is some material that is a bit too brittle, and has started to crack under load.
Most of the stresses will be from manufacture: extruding/rolling it to get a bar, then bending it.

In a bend like this, the biggest tensile stresses are on the outer surface, and they generally transition through to neutral somewhere in the centre, and on the inner surface they become compressive.

It’s possible that some surface corrosion and or wear has made a stress raiser, that caused the stress to start a crack growing.
And as it grew, that relieved the stresses, and the crack(s) stopped before going all the way through: at least it looks like they stopped.

I don’t think from what we can see that it is scc, because if it was then the cracks would not have stopped. Because the toughness of the material would have been affected by the scc.

Sure one might still argue it was SCC, and that the cracks just stopped because they hit the inner compressive stress, but then you’d expect to see just the one crack, and not multiple.

So i THINK a likely reason is the material is pretty brittle, and when the cracks started, that made that part of the bend relax enough to relieve the stress. But the other regions, being brittle, weren’t relaxed by that, and could also start to crack.
So enough of this partial cracking occurred to allow the entire bend to relax enough that it didn’t crack all the way through.

But it is obviously much weaker due to these cracks. And also because i suspect the material is not what it was supposed to be.

Another possibility is that the surface treatment of the material was substandard, and allowed it to be attacked.

Looking at the surface it seems like not stainless, any idea what it is?
Is it strongly magnetic?

Best,
Alan
Climb ZA - Administrator
justin@climbing.co.za

User avatar
XMod
Posts: 931
Joined: Tue Jun 26, 2007 9:38 pm
Real Name: Greg Hart

Re: Possible SCC on Wastelands Hellfire

Post by XMod » Thu Sep 13, 2018 10:28 am

Alan et al: I'm not sure if these were 316 or 318 family of steels (very early versions were 316 which still rusted, later versions were 318 which is virtually impervious to corrosion). They were made for Sean by ship building engineers. Later versions were pulled around a larger dye that didn't induce the cracking. I doubt any form of surface treatment was used to secure against corrosion, even if there was some treatment this would have been destroyed by contact with the epoxy (it gets on peoples fingers during placement which they then unwittingly smear on the bolts), early epoxies were extremely acidic(?) and would etch the surface of the steel heavily leading to surface corrosion in that spot.

The rings were pull tested, in the test, the river boulder they were set into shattered at 3500 k/N (or is that 3,5kN? - can never remember how to write that) with little or no deformation to the ring bolt. Another test (shear) threatened to break the rig and was stopped. Suffice to say they are stronger than any piece of climbing gear by a large margin. Anyway this is all a little academic as we dont use these anymore. The few that are still in the rock in various places have not exhibited any signs of failure nor even degraded much over the 30 years they have been in place - hence my lack of concern about their integrity.

We will probably replace this particular bolt because of the crack. Its funny though that the purpose made Raumer bolts we use nowadays are not of such high quality steel! :) (Although they are better with good quality control and surface treatment). I'm not looking forward to cutting this out of the rock - if it is 318 its going to be a struggle even with an angle grinder! :|

Andy Davies
Posts: 348
Joined: Wed Jul 06, 2005 12:37 pm

Re: Possible SCC on Wastelands Hellfire

Post by Andy Davies » Fri Sep 14, 2018 12:22 pm

A couple of observations from the back seat here:
  • 318 stainless steel is more commonly referred to as 316L
    the "purpose made Raumer bolts we use nowadays are not of such high quality steel" are made from 316L [or 318]
    316L does not normally exhibit a brown patina like this but will remain a silver colour. It could be some form of heat treatment or a lower quality steel like 3CR12
    The cracks are manufacturing flaws as a result of the bending process.
    Home made safety equipment is dangerous hence ARFs drive to procure and install good quality gear
AndyDavies

User avatar
XMod
Posts: 931
Joined: Tue Jun 26, 2007 9:38 pm
Real Name: Greg Hart

Re: Possible SCC on Wastelands Hellfire

Post by XMod » Mon Sep 17, 2018 12:12 am

Thanks for clarification - you are the expert. Was it not you who did the testing on the original ring bolts??
The Raumer bolts show signs of rust quite quickly - have a look at the ARF bolts at Kalk Bay. They showed spots of rust within two weeks of placement - hence my contention that the steel was not as good as the last set of rings Sean had made which are still silver some 20 years in.

Post Reply