The Bolting End-Game

SpencerB wrote: It might not result in quite as low a cost but a group buy company like massdrop could also be an option and not require one individual to take on the organization and upfront cost. I created a poll ( dro.ps/v/gBrjMiE). If enough people show interest by voting, they will normal contact the manufacture and set up the sale.

Waste of time, I don´t negotiate with internet marketing companies only climbers direct. Nothing in massdrop´s business model has any relevance to US climbers buying bolts and they want their cut as well so they would be more expensive (ca 10% + shipping).
Just contact mattm who I´ve dealt with before or whoever.

I've started speaking with a few people via email. Likely will happen and Jim and I have already chatted about an order prior to this coming up on MtnProj. Once I have some basic numbers I can follow up with those that are interested. PM me

Jim Titt wrote: In simple terms that means Hilti say products made of 316 are expected to have an economic lifetime of 50 years in a marine environment.

It's important to understand how "marine environment" is defined.

For example, a piece of 316 submerged in seawater full-time may last much longer than a piece of 316 installed in a limestone outcrop along a coastal cliff, where there is abundant vegetation and groundwater flow that changes the geochemistry, and thus corrosivity, of the environment. There are so many variables to consider that can have a huge effect on what happens empirically.

So what measuring stick are they using when they say "marine environment"?

cashmab wrote: It's important to understand how "marine environment" is defined. For example, a piece of 316 submerged in seawater full-time may last much longer than a piece of 316 installed in a limestone outcrop along a coastal cliff, where there is abundant vegetation and groundwater flow that changes the geochemistry, and thus corrosivity, of the environment. There are so many variables to consider that can have a huge effect on what happens empirically. So what measuring stick are they using when they say "marine environment"?

EOTA defines by examples what is meant by a marine environment and an agressive environment, the approvals are available for anyone to read.
In the construction industry/civil engineering the user is required to know or identify any specific problems which may occur, taking groundwater or run-off samples is standard practice.
The ETA for both the resin and the fastener are anyway void if you install in a limestone cliff, approval is specifically only for concrete and masonry. It is hard to understand why or how the UIAA intend to use the ETA as justification for a "guaranteed" life of 50 years in unspecified natural rock.

Hi Bruno.

Let me add to your post some things that are not very well known since research on this topic is on-going and only interesting to a few groups; climbers being one.

Bruno Hache wrote:Now, what is happening when sodium chloride is present? Well, one briefly explained. But in more depth: The higher the concentration of an electrolyte for any electro-chemical reaction, the faster the electrons will flow to the cathode. Salt water contains 3.5 % sodium chloride, the main culprit of stress corrosion cracking also misnamed salt-corrosion cracking in marine/coastal areas. First, sea salt moisture spray on a bolt. Then the sun comes out, the water dries out. In the process, the sodium chloride dries out too. Next spray of sea water, sodium chloride concentration is now increased due to the presence of dried out sodium chloride from the previous cycle.

It turns out that Mg+ and Ca+ are also dissolved in sea water in significant amounts. When the water dries out, the Cl- prefers the Mg and Ca over the Na, forming a MgCl2 and/or CaCl2 paste. This paste-state persists much longer than the wet and fully-dry states, drawing enough moisture from the air to keep from drying out (the temperature gradient and being in a crevice helps).

Both MgCl2 and CaCl2 are much more highly corrosive than NaCl, with CaCl2 being the worst. (see Prosek 2008) This is what is cracking stainless bolts.

That said, the sea does NOT need to be involved. Rainwater dissolves limestone CaCO3; calcite or CaMg(CO3)2; dolomite, producing Ca+ and Mg+ ions in the runoff. Rotting plants produce carbonic acid which accelerates the dissolution and acts as a corrosive catalyst.

Chloride ions are everywhere on the earth, and thus you get the same result: CaCl2 paste on the bolts. But because the concentration of Cl- on the earth is much lower than in seawater, and rain runoff produces much less Ca+ and Mg+ than in seawater, the rate of corrosion is much lower. Cracking still happens, it just takes longer, all else being equal.

Bruno Hache wrote:The higher grades of Stainless would prevent issues with the 304 or 316 grade for sure.

While this has been conventional wisdom for many years, tests that are in progress today indicate that higher grades, such as 2205 and 904 stainless, ARE corroding in harsh conditions. Ti is currently the only material, of those considered and tested, that is impervious to corrosion in harsh conditions.

Bruno Hache wrote:One of the highest grade used in corrosion proof chemical reactors is called Hastelloy ($$$$$). However, the higher the stainless grade, the higher the Nickel and Chromium content, the higher the price for the metal and we are now in Titanium price range, which most people cannot afford out of their own pockets. Hastelloy would be even higher $$$$ than Titanium!!!

Back in 1999 we considered Hastelloy C and found it was 2-4 times the price of Ti! It's also absurdly heavy!

Bruno Hache wrote:All good points! Yes, Magnesium and Calcium doing a paste, all chalk user have seen the Magnesium paste on chalked up holds after the rocks get wet.

No, not the same. Wet chalk is still MgCO3, Magnesium Carbonate. The paste I'm talking about is MgCl2, Mag Chloride or CaCl2, Calcium Chloride.

Bruno Hache wrote:I would add the Magnesium also act as a dehydrating agent. Calcium to less of an extent. So Magnesiun gotta keep the water for longer before it dries compared to Calcium.

Magnesium by itself is a metal, so not a dehydrating agent. MgCO3, chalk, dries your hands by being a dry powder, not via any chemical reaction. Same for Calcium.

As far as "keeping the water"... I don't know what you mean.

Bruno Hache wrote:Also to consider, MgCl2 and CaCl2 are a bit acidic when dissolved in water. Acidity must also be a corrosion factor to consider.

No. Acidity, by definition, is the presence of the hydrogen ion, H+ in water. Carbonic acid, H2CO3, is produced by rotting plants and contributes to the progression of SCC in stainless bolts not only by assisting the dissolution of limestone in rain, but by acting as a catalyst to the CaCl2 on the steel.

Bruno Hache wrote:But my point was, at large, inland climbing areas are less corrosion prone than sea shore by the simple presence of sea water spray (Sodium, Magnesium, Calcium). Not all inland limestone climbing areas are very corrosive. When they are dry, the metal rust much more slowly. I saw a 1000ish carbon steel studs with barely any rust at a local dry climate limestone climbing area. It always depend of each area, mineral composition, rock porosity and climate to name a few factors.

All true. But now you're talking about mild/plated steels compared to stainless, and oxidation compared to SCC.

Bruno Hache wrote:I am a chemist for a living.

Congratulations.

Bruno Hache wrote: Magnesium and Calcium doing a paste, all chalk user have seen the Magnesium paste on chalked up holds after the rocks get wet.
I would add the Magnesium also act as a dehydrating agent.
Calcium to less of an extent.

Excuse me but, "Magnesium and Calcium doing a paste" is something a professional chemist should NEVER say. Mg and Ca don't "do" pastes. It's a totally ludicrous statement considering the discussion concerned Mg & Ca cations and the differences between Mg/Ca Carbonate and Mg/Ca Chloride.

Bruno Hache wrote:Inland wet climate Limestone climbing areas are more subject to stress-corrosion cracking such as Red River Gorge.

The Red River Gorge is not limestone.

Bruno Hache wrote:
MgCl2 + H2O --- > MgO + 2 HCl
CaCl2 + H2O --- > CaO + 2 HCl

Sorry Bruno, but you've oversimplified. Throw in some Na, a lot of CO3 and let it dry out enough to form a paste (approx 50% humidity). What happens to the HCl, eh?

Bruno Hache wrote:If it is truly Magnesium chloride, I am not convinced, it is more likely the carbonate, especially in Limestone, and/or Calcium chloride, Limestone IS primarily Calcium Carbonate, but if it is truly MgCl2 or CaCl2, you generate some hydrochloric acid per the equation above.

First of all, the corrosive effects occur after the water dries and inside a crevice, which greatly affects the environment and reactions.

The salts, MgCl2, CaCl2 & NaCl exist in an unusual "semi-liquid paste" for long periods of time by drawing moisture from the humidity in the air (see Prosek, below). If the humidity is too low, the salts dry-out, stopping the corrosive process. If the humidity is too high, the salts are liquefied, and again, the corrosive process stops.

Secondly, analysis shows that the rain runoff contains, among other things, Mg, Ca, Na, Cl, CO3 and carbonic acid. These are the things found on the bolts and inside the cracks (via EDS analysis).

Bruno, I'm not guessing at what happens but you don't have to believe me. Go get the following articles, read them, and then you can argue with Sjong, Prosek and Karalis, and not me.

Marine Atmospheric SCC of Sensitized Stainless Steel Rock Climbing Protection
A. Sjong, L. Eiselstein
ASM Journal of Failure Analysis and Prevention, (2008) 8:410-418

Low-Temperature Stress Corrosion Cracking of Stainless Steels in the Atmosphere in the presence of Chloride Deposits
T. Prosek, et al
Corrosion vol 65, No. 2 (2009)

Failure analysis of a rock anchor made of stainless steel in marine environment
D.G. Karalis, et al
ELSEVIER Engineering Failure Analysis 19, (2012) 123-130

(Unpublished) Formal Analysis of Sport Climbing hardware
B. Fuller, (2004)
Autoliv, by request

Alright,
Consider I typed this from an iPhone, easy to miss:
"Excuse me but, "Magnesium and Calcium doing a paste" is something a professional chemist should NEVER say. Mg and Ca don't "do" pastes. It's a totally ludicrous statement considering the discussion concerned Mg & Ca cations and the differences between Mg/Ca Carbonate and Mg/Ca Chloride. "

Whatever dude.

Thanks for the articles.

I am done here.

bus driver wrote:Is there any non destructive testing methods for carbon steel bolts ? Ie could you run a current and map it to see how much mass is left. This could be compared to known specs. Good bolts could be left for future testing and corroded bolts could be pulled. Now, anything with surface rust is assumed junk but people seem to agree that surface corrosion does not equal weakness.

If you can provide me with bolts, I can take the ut readings on them and pass this on to someone for pull testing (unless you give me a machine). You would also need to know the exact original diameter (down to .01) for an accurate test. I don't know the QC on bolts forever Y company but can
Ask the Hilti guy what theirs is.

We have never had a case of stress corrosion cracking on Stainless Steel here in Red River Gorge and do not anticipate it ever being a problem here.

DrRockso wrote:We have never had a case of stress corrosion cracking on Stainless Steel here in Red River Gorge and do not anticipate it ever being a problem here.

That's because you are in the sandstone red river gorge, it's the limestone RRG where the SCC problems are happening;)

There is actually one Limestone route here :P The band of rock below our sandstone is limestone but it's almost 100% underground besides a few spots by the river. Lot's of Karst here in KY, the 2nd largest cave system in the world, but it's all underground! Who wants to bolt some stuff underground!? John will we need Ti?

DrRockso wrote:There is actually one Limestone route here :P The band of rock below our sandstone is limestone but it's almost 100% underground besides a few spots by the river. Lot's of Karst here in KY, the 2nd largest cave system in the world, but it's all underground! Who wants to bolt some stuff underground!? John will we need Ti?

That would be pretty awesome, and yeah, Ti would probably be the way to go.

DrRockso wrote:There is actually one Limestone route here :P The band of rock below our sandstone is limestone but it's almost 100% underground besides a few spots by the river. Lot's of Karst here in KY, the 2nd largest cave system in the world, but it's all underground! Who wants to bolt some stuff underground!? John will we need Ti?

Didn't Sharma and partner put up a multi-pitch route that starts deep underground and climbs to the light? Ah, here it is... Shit, 13 pitches!

redbull.com/en/adventure/st…

:-) Yeah, Ti bolts. And lights, lots of lights for the GoPros.

Jim Titt wrote: Jim - Do you know anything about how customs handles the shipment? How have others fared in the past? I ask having several poor experiences with carabiners coming in and a less than understanding "customs agent" calling them some other BS that had a higher tariff. Bolts are technically "rock anchors" and come under miscellaneous metal parts which are duty free into the USA from Europe. The only hassle for our end is if the shipment is over €1.000.00 when we need to go through an export notification scheme which can involve inspection and costs us a fair amount of paperwork, under this value there´s not a lot of extra work involved. Karabiners would probably be assessed as sporting goods and get a tarif of somewhere in the 2.5%-6% region, unless of course you import them from somewhere the Americans are having an argument with in which case they may impose a tit-for-tat penalty duty. Or an anti-dumping tarif like Europe has for titanium from China.

N.America is one region; nowhere in East / South East Asia readily stocks and supplies quality 316 (or higher grade) steel rock anchors so I have to import everything.

Note readily stocks; you can pick up bolts here and there but nothing like a 300 plus piece order!