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Chiodare al mare? Dal Vangelo secondo me...

 
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MessaggioInviato: Mer Ago 29, 2012 8:55 am    Oggetto: Chiodare al mare? Dal Vangelo secondo me... Rispondi citando

Ho ricevuto varie chiamate per avere delucidazioni sul materiale da usare al mare dopo le recenti “problematiche” sugli acciai inox.

Premesso che sono un chiodatore e uno scalatore come tanti altri.
Premesso che anche io pago il materiale che metto.
Premesso che il materiale Kinobi che commercializzo è circa il 3% del mio introito e lo vendo perciò per passione.
Premesso che le problematiche erano note da almeno 15 anni (mio intervento ad un convegno UIAA), ma dal 2009 appariva sul sito UIAA pubblico.
Premesso che NON sono un esperto di metalli in senso stretto. E termini usati possono essere impropri.



Ci tengo a precisare, che non lo ha ordinato il padre eterno di chiodare tutto il chiodabile ovunque esso sia. E senza voler offendere nessuno, l’ignoranza, confinante, per non dire unita, con la tirchieria degli arrampicatori, è smisurata. Mettere del materiale in giro pensando, che chi poi lo usa sia in grado di valutare minimamente la sua sicurezza, è utopico. Le falesia sono piene di cianfrusaglie e materiale usurato che è palese che gli arrampicatori non sanno i rischi che corrono, e se lo sanno, se ne fregano. Gli arrampicatori presumono che il materiale “in posto” sia sicuro anche se ha più di 10 anni, ma in realtà non esiste produttore o ditta che da garanzia per più di due/tre anni (ad esempio…
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oppure si vede il “nessuna garanzia" anche qui:
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Prima di continuare leggere il seguito, usate tre minuti per capire le problematiche su questi link:

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Molto meglio la versione in inglese:

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Consiglio anche di leggere questo topic, che pur infarcito di commenti da “forum”, ha spunti interessanti:

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Gli acciai inox, almeno alcuni, possono essere affetti da “Chloride Stress Corrosion cracking (SCC) e/o pitting:

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La cosa che interessa di questo link è la “temperatura superiore a 50 gradi”. I 50 gradi al sole, al mare, si raggiungono facilmente, in tante altre zone (anche al mare) invece sono una temperatura difficile da avere. La trazione (tassello) o piegatura dei resinati posso incrementare tali problemi.


In alcune situazioni molti tipi di acciai inox possono andare in crisi. Il zincato, di norma, ci va prima in crisi. Ovvero, ogni materiale è in grado di “digerire/combattere” una certa dose di agenti corrosivi. Oltre tale dose, il materiale ha dei problemi che possono portare a dei cedimenti. Ciò vale per gli ancoraggi come per le soste. Posizionare ancoraggi di un tipo di acciaio e soste di un altro, secondo me, è da stupidi. Non si risolve il problema, lo si aggrava.



Personalmente credo che un ancoraggio non possa costare più di 3,5/a euro cadauno. La sosta non può costare più di 20 euro. Oltre tali costi, è un problema di chiodatori retribuiti da enti, i quali hanno il dovere e l’obbligo di sapere perfettamente cosa fanno e cosa mettono.
Se il materiale costa più di tali cifre, non si dovrebbe usare = chiodare. Ovvero, si dovrebbe lasciare fare il lavoro solo a chi sa perfettamente cosa mette e cosa fa e presumo retribuito.



In SINTESI:

In zone con climi caldi, esposte a sud, vicine al mare o soggette a correnti del mare, l’unica soluzione pare sia il resinato in Titanio. Ammesso che poi la resina con cui è incollato dia garanzie nel tempo. Non riesco a trovare resine con “garanzia scritta” oltre i 3 anni.
Gli unici ancoraggi di mia conoscenza in Titanio sono:

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Non conosco l’esistenza di tasselli in Titanio, perciò mettere le placchette con tasselli in altro materiale è inutile nonché stupido.
Considerato che i costi del titanio per me non sono accettabili, non chioderei sul mare (esposto a sud) se non si prevede una frequente manutenzione. Cosa significa frequente? Non lo so, diciamo ogni 4/5 anni. Ma potrebbe essere anche meno. Siccome è una cosa che reputo “non realistica”, non chioderei.
Esistono anche questi prodotti, ma hanno un costo che non rientra nel range da me ricercato:

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Soprattutto non ho trovato una garanzia a vita sulla loro durata. E sono resinati, e non ho trovato garanzie sulla resina. Non vorrei perciò consigliare una cosa, di cui, tra 5/7 anni si sta a discutere "se andava bene".
Dal mio punto di vista, in zone “difficili” non si dovrebbe chiodare.
Cosa intendo per “difficili”: complesso da definire, ma roccie gialle (non soggette a precipitazioni), esposte a sud (al sole) a meno di 150 metri dal mare.


In zone con climi caldi non esposte a sud non troppo vicine al mare (oltre i 150 metri), userei acciai in inox 316. Devo dire che non credo accetterei i costi delle soste in inox di quel tipo. Non penso ci sia quella grande differenza tra 316 e 304 (ambedue da me commercializzati), ma pare che il 316 dia garanzie migliori e sosterrei il costo aggiuntivo.
lweggere cosa dicono nel 316

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In tutte le altre zone, oltre i 500 metri dal mare, metterei acciaio inox 304 facendo delle distinzioni sui vari tipi di roccia (gialla, grigia, soggetta a correnti, etc.).
In alcuni settori veramente distanti dal mare (centinaia di chilometri), esposti a sud, posso accettare il zincato anche se ho evidenza che oltre i 15 anni iniziano fenomeni di ruggine.


Come Kinobi le mie placchette spit sono vendute codificate (dalla seconda serie ovvero 2009). Il codice interno che indicava la partita di produzione non è facilmente “intuibile”, perciò in futuro il codice avrà il tipo di metallo (304 o 316) e l’anno di produzione (ad esempio 304X13= Acciaio inox AISI 304 A2 prodotta nel 2013).Vendo solo placchette con tassello dello stesso materiale, e consiglio di mettere il dado con la scritta visibile del tipo di acciaio all’esterno (“A2” o “A4” che siano visibili, non a contatto con la placchetta).


INFINE:
- chiodare dove si sa che possano esserci problematiche, non si dovrebbe fare. Il che significa anche mettere “zincato” al mare.
- chiodare dove non si controlla lo stato di conservazione del materiale, non si dovrebbe fare.Questo vale specialmente per chi va in un luogo “esotico” (sia la Sardegna o le Cayman Island) e lascia la riga di spit non curandosi di chi poi ci si attacco sopra dopo.
- se non si sa quel che si fa, e si usa, è meglio lasciare stare.
- NON mescolare mai i tipi di materiale.


Ciao,
E


L'ultima modifica di Kinobi il Mer Nov 02, 2016 1:20 pm, modificato 1 volta
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MessaggioInviato: Sab Nov 10, 2012 9:47 am    Oggetto: Rispondi citando

Dopo aver letto bene questo testo, non so se ci sia quella enorme differenza tra 316 e 304.
E

Qui trovate eccellenti informazioni.
Comprensibili anche per i non addetti ai lavori.
Ciao,
E

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MessaggioInviato: Mar Mar 26, 2013 6:26 am    Oggetto: Rispondi citando

Segnalo questo link, apparso ne la Metallurgia Italiana:
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Consiglio di leggere attentamente.


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ed in particolare questo:

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Segnalo (tratto da una mia email):

a) Pagina 27 in basso
a sinistra. Sia nel 304 che nel 316L.
b) XXXXfa in 316L ma non lucida, ovvero le fa satinate, come XXXX (le
Marine). Pagina 27 in basso a destra " raggiunge gli stessi livelli di
corrosione del 304".
c) Pagina 30: "Assai limitato è il vantaggio offerto dal più costoso AISI
316L".

Pagina 30. in basso a SX "Al termine del periodo di esposizione in
ambiente marino, l'acciaio AISI 316L ha mostrato lo stesso livello di
corrosione di quello del tipo AISI 304, inizialmente meno resistente. Al
contrario gli AISI 304 con finitura BA (non satinati) hanno mostrato
buona resistenza a corrosione purchè non utilizzati proprio a ridosso
del mare.


Detto questo il motivo per cui i tasselli possono fare più corrosione è
spiegato qui:

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Sfortunatamente, le rondelle le fanno tutti in Cina, come i dadi ed
arrivano SATINATE.

Amen.
E
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MessaggioInviato: Gio Mag 30, 2013 7:25 am    Oggetto: Rispondi citando

Una soluzione al mare potrebbe essere usare tasselli e placchette in 14529.
A pagina 39 del manuale di corrosione della Hilti si vede un grafico.
Molto evidente.
Chiaro.
Semplice.

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Fino ai 5 anni non esiste diferenza tra 304 e 316 o è minima.
Poi il 316 migliora.
Non è specificato il tipo di lucidatura (polishing) del materiale. Come spiegato nel post precedente, la lucidatura è molto importante, tanto da azzerare la differenza tra 316 e 304.


Nota: il 14529 costa nei tasselli circa 7 volte più del 304. Ignoro le placchette.
Ciao,
E
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MessaggioInviato: Lun Lug 29, 2013 4:33 pm    Oggetto: Rispondi citando


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Interessante.
E
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MessaggioInviato: Gio Apr 17, 2014 8:19 am    Oggetto: Rispondi citando

Con riferimento a questo testo (di un mio concorrente) ne segnalo l'utilità.
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Non sono d'accordo su molte cose che dice,ma le linee guida e base, sono molto utili.

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MessaggioInviato: Gio Apr 24, 2014 9:10 am    Oggetto: Rispondi citando


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Molto ben fatto.
E


Built to Last? The Hidden Dangers Of Climbing Bolts
Climbing anchors and corrosion
By Jeff Achey / Photos by Andrew Burr


Two climbers headed up a two-pitch sport route on the Fire Wall, above Tonsai Beach on the Phra Nang Peninsula of Thailand. At the two-bolt anchor, the leader pulled up slack to belay his partner, and as an afterthought, he reached up to clip the first bolt of the next pitch as a redirect to belay his partner.
When the second reached the belay, both climbers leaned out on the anchor to inspect the next pitch. Immediately both anchor bolts broke. The pair swung off their stance and hung suspended, 90 feet off the ground, by the single second-pitch bolt the leader had clipped as a redirect. That bolt didn’t break.
A climber on the Upper Town Wall at Index, Washington, was tackling a seldom-climbed 5.12 route named Calling Wolfgang. After climbing through some gear-protected terrain, he continued past several bolts. Now about 65 feet up, he clipped the third bolt he encountered, intending to hang and clean some holds. As he leaned back on the bolt, however, it broke. He fell about 15 feet until his weight came onto the bolt below, which also broke. Fortunately, the next bolt held, arresting the climber’s fall only 15 feet off the ground.
What caused these accidents? When new, these anchors could hold thousands of pounds, but now they had failed under body weight. None of the failed bolts looked all that bad, at least at first glance, and one was almost new. The story behind these near-catastrophic bolt failures is more complicated—and more common—than you might expect.
Free-for-all engineering
You read it all the time: The climber is responsible for his own safety and should evaluate every protection bolt he clips. True in theory, but in practice, most climbers don’t. Unless a bolt is so rusted that it looks like a relic, it’s generally considered good.
Yet bolting sport routes is a completely unregulated practice, carried out mostly by practitioners who are not only untrained, but often are functioning on dangerously tight budgets. Skimping on materials can save $100 or more per route—a week’s living expenses at Miguel’s or Rifle Mountain Park. At the same crag, some anchors will be “by the book,” while others are creative combinations of bolts, chains, and hangers chosen to save cost, and some are poorly placed due to lack of knowledge. Some anchors are exposed to unusual corrosive forces that have surprised even trained specialists.
“The result is a high degree of variability in strength and lifespan of the anchors out there,” says Bill Belcourt, Director of Research and Development at Black Diamond Equipment. “It is apparent there is no standard practice or training for placing bolts, and this is a big problem that is compounding daily as more routes are being developed and existing anchors age.” Many feel we have outgrown the “wing-it” phase in our equipping and should become a little more standardized and responsible.
Alan Jarvis of the UIAA Climbing Anchors Working Group, certainly feels that way and compares climbing to other instances where bolt failures can cause dangerous accidents. “The construction and oil and gas industries use a lot of fasteners, as they call bolts,” says Jarvis. “The engineers specify what anchors to use and plan for a defined lifetime. Fifty years is considered normal. On big projects they have a quality-control system in place to inspect critical anchors after installation, as well as during their lifespan.”
“In climbing, however, quite often the person who decides on the anchor doesn’t know that much about materials or corrosion. They are not materials specialists. They are not certified or specially trained, as welders on pipelines, etc., are. Nobody inspects the bolts after or during installation, or during their lifetime. And there is no pre-determined lifetime, or replacement program.”
Now, just over 20 years since bolt-protected climbing took hold in the U.S., the first-generation routes in most parts of the country have become unsafe. Many crags have already begun re-equipping, and the hardware is well into its second round of wear. In remote locations lie classic routes that are unclimbable due to inadequate hardware. It doesn’t have to be this way.
Should climbers be inspecting the bolts they clip? Of course. But how? Can you tell by looking at a bolt if it’s safe? Perhaps more importantly, how can a route developer or anchor-replacement volunteer choose a bolt that will be good for 50 years?
Metal-urgency
It’s easy to spot a very rusty bolt, but the most dangerous kinds of corrosion are less obvious. Inexpensive carbon-steel bolts rust predictably—quickly or slowly depending on the environment—and get weaker and weaker as the steel gradually flakes away as rust. On the other hand, corrosion-resistant hardware such as stainless steel, doesn’t rust as noticeably. But it can be attacked in other ways—sometimes rapidly.

Brittany Griffith climbs in Playa Fronton, Dominican Republic, an area very affected by the rapid degradation of metal hardware.
Most anchor hardware is made of steel, which mainly consists of iron, plus a mix of other things. Iron rusts when it reacts with oxygen. Water speeds up the process, too: Oxygen in dry air tends to stay in the air, while oxygen plus water plus iron equals rust.
Saltwater accelerates rust even more. Dissolved salts become positive and negative ions, so they make saltwater a much better conductor of electricity than freshwater, which speeds up the chemical reactions of corrosion. Heat also increases the speed of corrosion. All else being equal, climbing bolts will rust faster in Alabama than in New Hampshire. Acids—even mild ones such as acid rain near industrial areas—will significantly increase corrosion. Groundwater affected by decaying vegetation becomes acidic, like vinegar, and will rust bolts faster—sometimes much faster.
There are many kinds of steel, but the simplest ones are over 95 percent iron, plus a small percentage of carbon. Pure iron is actually softer than aluminum, and carbon gives “carbon steel” its strength and hardness.
Of the hundreds of kinds of steel, some are designed to hold a sharp cutting edge, some to be malleable, others made to flex and spring back into shape. You can completely alter the properties of steel by changing the carbon content, heating and then cooling it in a certain way, or by mixing it with other metals. Steel is amazingly versatile, but its main drawback is and always has been its susceptibility to rust. It’s the only metal that corrodes so badly in typical environmental conditions.
The main reason is that rusts—iron oxides—have the unusual property of being soft and powdery. They flake off, taking the metal with them, so the surface just dissolves away. Rust is oxygen-permeable, so the inner metal continues to oxidize. This is unusual for metal oxides, as most others form a hard, resilient film on the surface that protects the base metal from corrosion. Fortunately, by mixing other metals into the steel, you can create alloys that will form a much more protective surface layer.
The best-known steels of this type are “stainless” steels, a large family of over 100 alloys that share the characteristic of containing at least 10.5 percent chromium. Somewhat counterintuitively, chromium makes steel “stainless” because it is even more reactive with oxygen than iron. But instead of forming a flakey rust, stainless steel develops a thin surface layer of chromium oxide that keeps the steel from rusting. It’s self-healing—if you scratch or gouge the steel, new chromium oxide forms to protect it.
Chromium makes steel brittle, however, so most stainless also contains nickel, which counteracts chromium’s brittleness and adds its own corrosion resistance. Nickel is also what makes stainless significantly more expensive than carbon steel.
There are many grades of stainless, but the most common one for climbing-anchor hardware in the U.S. is SAE 304, sometimes called 18/8 because it contains 18 percent chromium and 8 percent nickel. “Marine-grade” or SAE 316 stainless is similar, but in addition contains 2 percent molybdenum, a pricey metal that makes 316 more resistant to the crevice and pitting types of corrosion that can plague stainless steel in “aggressive” (highly corrosive) environments. In the U.S., 316 stainless costs 35 to 40 percent more than 304, but in Europe, where 316 is favored, the cost difference is less. Many European-made stainless hangers, including those donated by Petzl to Climbing’s Anchor Replacement Initiative program (climbing.com/ari), are 316.
There are other steels with significantly more corrosion resistance than 304 and 316. Some are prohibitively expensive, but some could be viable for climbing anchors. One such group are the so-called HCR (high corrosion resistance) steels, which contain more molybdenum and nickel, and their molecular structure is enhanced by other elements such as nitrogen. One widely used HCR steel is 254 SMO. With 6 percent molybdenum and 18 percent nickel, 254 SMO is significantly more expensive than 316, but it is very resistant to the special kinds of corrosion—pitting, crevice corrosion, and SCC—that can plague climbing anchors in aggressive environments.
In the construction industry in Europe, outdoor safety–critical steel anchors must be either 316 or HCR; the less expensive 304 is not considered adequately corrosion-resistant.
Nickel and molybdenum make stainless steels expensive, and there is a cheaper way to keep steel from rusting: plate it with zinc, a process sometimes called galvanizing. This can be done either by dipping the steel in molten zinc, or, more appropriate for climbing-anchor hardware, applying the zinc through an electrical process. Zinc costs about the same as aluminum (one-eighth as much as nickel), and electroplating requires little zinc anyway. Like the chromium in stainless steel, zinc oxidizes readily, forming a protective layer that keeps oxygen away from the iron.
Stainless steel has its corrosion resistance built in, but plated steel doesn’t: Zinc-plated steel will slowly lose its zinc to oxidation. In wet climates, it doesn’t take long for the zinc to be used up. No zinc, no corrosion-resistant veneer.
Most of the carbon-steel bolts still used at U.S. climbing areas—the Rawl/Powers “5-piece” sleeve bolts, for example—are zinc-electroplated. Plated-steel bolt hangers are significantly less expensive than stainless and are widely used in the western U.S.
Of course, no discussion of corrosion-resistant metals would be complete without mentioning titanium, “metal of the Titans.” Titanium is pricey, but not obscenely so, and has a higher strength-to-weight ratio than steel, as well as excellent corrosion-, fatigue-, and crack-resistance. Titanium bolts are becoming the standard at tropical climbing areas, and the first UIAA-certified titanium anchor is now on the market.
Currents, crevices, and cracks—special types of corrosion

Metal rusted by saltwater in the sea stacks of Scotland.
Not all corrosion is as gradual or easy to detect as rust. One equipping mistake that speeds up corrosion is to mix two kinds of metal in the same anchor—a stainless steel hanger on a carbon-steel bolt, for example. Such setups may suffer from “galvanic corrosion.”
As the name implies, galvanic corrosion involves an electric current. Metals each have their own “electrode potentials”—the potential to become either a positive or negative pole of an electric couple. If the potential of two adjacent metals isn’t the same, a small current, carried by electrons, flows between them. Seeking a sort of equilibrium, the metal donating the negatively charged electrons will also begin to lose positively charged metal ions, causing the metal to dissolve.
Galvanic corrosion won’t occur in dry conditions or in distilled water; to “complete the circuit” you need an electrolyte such as saltwater. In climbing anchors, any mineralized water trapped between a bolt and its hanger will function as the electrolyte.
Various combinations of mild steel, zinc-plate, aluminum, and stainless can experience galvanic corrosion. Installing a stainless hanger on a carbon-steel bolt will compromise the bolt itself, while a zinc-plated hanger on a stainless bolt will compromise the hanger.
Crevice corrosion is also relevant to climbing anchors. It is caused by the concentration of corrosive minerals, especially chlorides. Crevices in or around the metal tend to trap mineralized moisture. If the crevice periodically dries out, it can concentrate dissolved chlorides and create a microenvironment so aggressive that it can overwhelm the oxides on stainless steel.
It’s commonly believed that only crags near the ocean are at risk for aggressive corrosion because of the chlorides carried by seawater. In fact, chlorides are also carried by rain and especially groundwater. The initial amounts may be small, but evaporation can concentrate chlorides within crevices.
Climbing anchors are rife with crevices, including the threads, sleeves, and wedging collars, behind washers, and where the hanger bears on the bolt stud. Bolt holes themselves create crevice-like conditions quite unlike those on the rock surface. Water soaks into sandstone, percolates through limestone, and even in dry climates like Colorado, the shafts of rock climbing bolts typically live out their years in a state of dampness. If they dry out completely once in a while, that’s actually worse, since it serves to concentrate corrosive salts. This highlights advantages to glue-in bolts: 1) they have no crevices, and 2) the epoxy protects the metal from the corrosive microenvironment inside a bolt hole.
Crevice corrosion affects all steels, but it is particularly disturbing in stainless steel. A stainless steel bolt/hanger combination will almost never show surface rust. The bolt may look fine, yet be badly corroded in critical, invisible areas such as the threads.
Pitting is another special kind of corrosion. This one you often can see, since it takes place on exposed surfaces such as the face of a bolt hanger. It is essentially a microscopic version of crevice corrosion. Stainless steel’s chromium oxide layer contains minute flaws that can become tiny pits. Once a pit starts, it can create its own microenvironment with an aggressive chemistry that allows corrosion to proceed.
Pitting is still an active field of study among metallurgists, but it is definitely linked to mineral inclusions. Sulfur, for example, is often purposely added to stainless steel to make it easier to machine (SAE 303 is one example—avoid it!). Sulfur inclusions, however, when exposed on the surface of the steel, create a break in the chromium oxide layer where pitting can begin.
One final kind of corrosion of real consequence to climbers is stress corrosion cracking. “SCC” is technically more than just corrosion. It’s a double-whammy interaction between chemical corrosion and mechanical stress. In the wrong conditions, SCC can rapidly destroy stainless steel climbing hardware.
SCC is a devious, hard-to-predict process with a history of making catastrophic surprise appearances. Beginning in the early 1990s, it has been responsible for an epidemic of climbing-anchor failures at tropical crags worldwide.

Metal rusted by saltwater in the sea stacks of Scotland.
If a metal is susceptible—and stainless steel is—several factors must be present for SCC to occur. One is stress within the metal. This is universal in climbing anchors. Mechanical bolts are put under tension when they are tightened. The bolt/hanger metal retains internal stresses from the “cold-working” processes of manufacturing—punching the hole and putting in the bend, for example.
The last necessary ingredient for SCC is an aggressive environment. Here’s where prediction gets complicated, because the microenvironments within and around a climbing anchor can become aggressive in many subtle ways. SCC was originally associated with industrial sites such as boilers and desalination plants. High heat, lots of salts. Yet SCC was later found to occur at much lower temperatures—around indoor swimming pools, for example.
SCC is only associated with very high concentrations of chlorides. Unfortunately, both the geology of certain cliffs and the microenvironments within bolt holes can help create the aggressive conditions needed for SCC to occur. It can make the face of a stainless steel bolt hanger look like shattered glass.
The incidents analyzed
If you hadn’t guessed already, the incident in Thailand relayed at the beginning of this story was a case of SCC. One of the anchors that broke was a ½-inch stainless steel bolt that had been placed only 18 months before.
This was just one of many stories climber Sam Lightner recalls from the early days—the mid to late 1990s—of chronic anchor failures in the tropical climbing paradise of Thailand. “It was a strange thing,” says Lightner. “Some walls seemed OK, and some were eating the steel fast. We now realize it had to do with temperature. The walls that face the sun for a good bit of the day get incredibly hot, increasing the speed of the chemical reaction. Some of the walls that never saw the sun took many years to visibly show the problem.”
Climbing-anchor SCC was also later discovered to involve factors that had never been documented by materials specialists. The mechanism was discussed in detail in a 2008 paper by climber and metallurgist Angele Sjong, published in the widely read Journal of Failure Analysis and Prevention.

Metal rusted by saltwater in the sea stacks of Scotland.
At that time, Sjong (wife of the well-known climbing athlete and coach Justen Sjong) worked at the renowned engineering consulting firm Exponent, in the California Bay Area. Though she had never been to Thailand, she had heard from climbing friends about the terrible corrosion problems there. When Greg Barnes of the American Safe Climbing Association brought her a broken bolt hanger, she agreed to do a quick analysis.
When Sjong looked at the specimen under the scope, she couldn’t believe the severity of the corrosion. “It was a crowded day in the lab,” she says, “and I said, ‘Hey, check this out!’ Everyone was stunned.” Exponent is one of the most respected failure-analysis firms in the world, but none of the experts had seen ambient-temperature SCC like this. One senior analyst said, “We should look into this.” Sjong launched a literature review and a battery of tests that culminated in the journal paper.
The incident at Index could be blamed on several factors. From a materials perspective, galvanic corrosion was responsible for the incident: The route featured aluminum hangers on steel bolts, which had been in place for almost 20 years at the time of the incident. Aluminum hangers are still available—Petzl makes some—and are favored for deep cave exploration for their strength and light weight, but aluminum and steel make a very active galvanic couple. With almost 70 inches of rain per year, Index is wet enough to keep the galvanic “battery” going, dissolving enough aluminum near the hanger/bolt attachment point that the hanger sheared off under body weight.
But there is also a social factor. The route was established around 1990, amid the “first generation” of sport-style bolting that swept across the U.S. During those Lycra-clad days, bolting wisdom was all over the map, and with angry trad climbers often ready to chop the routes, the whole concept of bolt longevity was basically off the radar. The equippers were functioning at the normal standard of the day: Routes were equipped with random hardware that was either imported, purchased at the local hardware store, or homemade—sometimes all of the above—and mixed and mismatched.
The human side
An improvisational, skimp-and-save philosophy lingers to this day, and there is still a dangerously lean knowledge base about climbing-anchor longevity. Even among knowledgeable route developers dedicated to “best practices,” there is still plenty of disagreement. Is stainless steel necessary in drier environments such as Lander, Wyoming, or Indian Creek, Utah? Coastal climbing areas obviously need corrosion-resistant hardware, but how resistant: Is titanium necessary for non-tropical areas such as Kalymnos, Greece, or Mickey’s Beach, California? Open questions, all of them.
In November 2012, the Access Fund held a conference in Red Rock, Nevada, called the Future of Fixed Anchors. One reason was the amount of time and money now going into re-bolting efforts. “The old bolts from the beginning of the sport climbing era are in need of replacement,” says Brady Robinson, the AF’s Executive Director. “Some people are doing a great job replacing them, and others are, frankly, botching it.”

Metal rusted by saltwater in the Dominican Republic.
Kenny Parker is chairman of the Anchor Committee for the New River Alliance of Climbers (NRAC) in West Virginia, one of the earliest and most effective anchor-replacement efforts in the country. Yet Parker claims that money and man-hours haven’t been the biggest hurdles. “Even more than doing the actual work,” says Parker, “the biggest challenge has been pulling together the community around a process and a plan.” In other words, consensus.
Parker suggests that the average original sport route in the New River Gorge (annual rainfall about 50 inches) proved to have a life expectancy of about 10 years. In drier areas such as Rifle, Colorado, most routes lasted 10 to 15 years. It’s clear that our original attempts to create sport routes in the U.S. also created a massive maintenance problem just a few years down the road.
“In 100 years, I for one don’t want every popular route to have five holes at every clip,” says Robinson, “evidence of generations of climbers’ efforts to upgrade the anchors with the times. We can do better.”
Alan Jarvis of the UIAA agrees. “I think that the most important thing here is to establish a specific lifetime for anchors,” he says, strongly suggesting 50 years as a baseline. “It doesn’t have to be 50 years, but it needs to be specified. Once you agree on a specified working life, then everything else falls into place.”
International standards for corrosion resistance
So let’s say you’re an equipper and buy into the concept that re-bolting a route every 15 or 20 years doesn’t cut it. How can you know what hardware to use at your area to get a 50-year lifetime? The UIAA is in the process of rolling out guidelines that will help.
“Let’s say you’ve heard that Bolt A is more corrosion-resistant than Bolt B,” says Jarvis. “Is it even true? And do you really need that? Who knows? The UIAA is working to have a classification system based on the corrosion resistance of an anchor.”
The specific tests will be some version of standard tests used in other industries. Significantly, only complete anchors—one-piece glue-ins or complete bolt/hanger combinations—will be tested. A bolt or a hanger alone will not be eligible for classification. In a nutshell, here’s what the system will look like:
Class 1 anchors will have to endure severe testing conditions and prove themselves extremely resistant to normal corrosion, crevice corrosion, pitting, and stress corrosion cracking. Anchors in this class are what places like Thailand will need. The UIAA safety commission decided on the specific tests for this class during their meeting in Chamonix in June 2013.
Class 2 means moderate to high corrosion resistance. “This is likely what other coastal areas need,” says Jarvis, “where there is some risk of SCC, but not as extreme as in tropical areas.” It will be interesting to see what tests the UIAA comes up with for this class, and what metals will pass, since, despite its susceptibility to SCC, 316 stainless is widely used for anchor replacement in such areas, and there is significant resistance to upgrading to much more expensive alternatives such as titanium.
Class 3 anchors will have “moderate” corrosion resistance. There will be no tests for SCC. Anchors in this class should be suitable for the bulk of climbing areas that have no special corrosion concerns, and it will be the minimum level of corrosion resistance recommended for outdoor climbing. Since this standard is being generated in Europe, it seems very likely that anchors in this category will have to show corrosion resistance equal to 304, and possibly 316 stainless. If so, this requirement is sure to cause some controversy in the U.S.
Class 4 anchors will have no specified corrosion resistance and be aimed at indoor use.
Manufacturers will not give any specific lifespan warranty after these tests. Rather, it is a tool for consumers. “If one matches the right anchor class with a given climbing environment,” says Jarvis, “then a 50-year (or more) lifetime should be achievable.”
The future

James Garrett gets high off the ground on the Original Route (5.10b/E1 5b), Old Man of Hoy, Scotland, where plenty of fully rusted hardware can be found.
We are nearing the end of seat-of-the-pants bolting. If the UIAA stays on course, it will soon have standards for climbing anchors that—barring placement errors or mismatches between hardware type and environment—should allow us to choose anchors that will last 50 years. The Access Fund is currently assembling a web page of “best practices” for anchor placement. The question is, how quickly will bolters upgrade their habits?
“Land managers are beginning to move toward telling climbers how to place or replace bolts, and which kinds to use,” says Robinson. “If we don’t have any consensus in our community and without hard science to back up our actions, how are we going to prevent bureaucrats from dictating bolting practices?”
Historically, cost has been a very important criterion for choosing climbing anchors. That will probably never change. But actually, it doesn’t need to. Anchors made from corrosion-resistant metals cost more up front, but if they last three times as long as cheaper anchors, in 50 years the climbing community will have saved money—and a lot of re-bolting effort.
That logic works well for community-funded re-bolting efforts, but not so well for first ascensionists, who, in the U.S. at least, almost always buy bolts with their own money. Spending to ensure 50 years of service can seriously slow down their effort.
“The Access Fund can’t just step in and tell people what to do,” says Robinson. “The hope is that long-lived bolts, and bolts that can be replaced without drilling new holes, will become more and more common. Great technologies are here or are on the horizon, but it only helps us if people use them.”
Special thanks to Greg Barnes, Bill Belcourt, John Byrnes, Steve Gladieux, Alan Jarvis, Sam Lightner, Josh Lyons of the Thai-tanium Project, Kenny Parker, Martin Roberts of Titan Cli
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Kinobi
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MessaggioInviato: Sab Apr 25, 2015 10:43 am    Oggetto: Rispondi citando

Con riferimento a questo topic, questa è la mia risposta.


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Titanium vs Stainless.

Titanium has some/many advantages. But it cost about 4 times more than Stainless and it has the issue with glue.
Most recent accidents that I am aware of (San Vito Lo capo (I), Val Daone (I), Valeria (E)) had issues related to the rock, not the bolts: the all piece of rock came out. Do you need photos?
This makes you think…

In an ideal world (safety of working places), you need to inspect gear and concrete/steel every given time. Everybody does it.
In an ideal climbing world you need to inspect gear and rock every a given time. Nobody does it.

My two cents is that Titanium is better, but had I to choose, I will take Stainless and inspected (rock and gear) every 10 years for the next 30 years, at the price of one single “forever” bolting with Titanium but with no future inspection of the place. Inspection means you check rock, replace worn carabiners, etc…

Said so, all the issues that I am aware of 304 (A2) and 316 (A4) in most parts of Europe are very difficult to compare with what is happening/happened in Thailand. Nobody says there are no issues in Europe, but I think the scale of the problem, needs to be considered and here is significantly way less problematic.
There are some parts of Kalymnos/Telendos that might have issues like in Thailand, but big majority, they have not. Climbing in Kalymnos, I am more afraid that with wind I get a rock in may face, or a belay pulls out attached to the rock, rather than a bolt breaks

Best,
E
PS: Climber, Equipper (+2500 bolts placed) and Bolt (stainless) producer
.
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MessaggioInviato: Mer Mag 06, 2015 1:17 pm    Oggetto: Rispondi citando

Perfetto esempio di differenza tra zincato e inox.


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MessaggioInviato: Mer Nov 02, 2016 1:56 pm    Oggetto: Rispondi citando

Recentemente sono tornato da un giro a Ibiza, come descritto qui:
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Sempre in questi giorni, ci sono varie fotografie di ancoraggi rotti in Sardegna in 304 al mare. Onestamente sono lustri che se ne parla, ma sembra che tanti "cadano dal pero" se gli resta in mano uno spit.

Sostanzialmente reputo opportuno aggiungere qualcosa ai commenti precedenti di questo tread, che erano stati scritta alcuni anni fa, dopo aver visto l'evolversi della situazione. Soprattutto, dopo il passare del tempo.

Il primo punto è che ancora non tutti i climbers hanno un'idea precisa delle problematiche dell'arrampicata al mare. Ovvero, troppi pensano tutto sia perfetto è sicuro: non lo è. Se in una falesia in montagna la vita "tranquilla" della chiodatura è più di vent'anni, al mare si ragiona in un decennio.

Faccio un mini sunto.

Al mare, l'ambiente è corrosivo, e gli ancoraggi ne risentono. Il che significa che si possano rompere. Individuare cosa non si rompe con certezza, è tutto sommato facile:
a) se avete fiducia cieca sulle resine, allora i resinati in titanio. Alla domanda ma dove si trovano, la risposta è ad oggi praticamente da nessuna parte o in pochi siti in Europa. Esiste un'unico tipo, per cui si dovrebbe fare lo sforzo di imparare a riconoscerli...
b) ancoraggi in HCR. Dove si trovano? Da nessuna parte al momento. Fino a che non ne verrano usati di più, i costi sono elevati.
c) ancoraggi galvanizzati, dove lo spessore rimasto della placchetta, o resinato, sia sufficiente. Cosa significa "sufficiente"? Almeno 3 mm.
In tutti gli altri casi, c'è la possibilità che vi resti in mano l'ancoraggio.

Gli ancoraggi in INOX 304/A2 hanno una vita utile tra i 5 e i 10 anni in ambienti corrosivi. Non significa tutti si romperanno, ma significa che si possono rompere. Oltre tali "scadenze", se non siete pratici, girateci distante.
Come riconoscerli è un bel casino:
a) se si tratta di tasselli e si vede, se c'è la scritta, A2 sul dado.
b) se si tratta di resinati, la quasi totalità, ad oggi, sono in 304/A2.

Gli ancoraggi in 316/A4 hanno una vita utile tra i 10 e i +15 anni.
Se si vede la scritta A4 sul dado, si può stimare la durata residua. Ce ne sono in giro, alle volte abbinati a placchette in 304 che risentono meno del problema.

Per cui, se andate al mare, o chiodate al mare, tenete conto di queste cose.
Ne va della vostra salute. E nel dubbio, contribuite con i chiodatori locali nel richiodare le vie. Se non avete intenzione di contribuire alla richiodatura, e/o non accettate i rischi connessi, e non siete in grado di individuare con esattezza il tipo di ancoraggio usato, giratevi dall'altra parte, fate due tuffi ed andate a casa.

Ciao,
E

PS: ci sono leggende metropolitane che parlano di costi spropositati dei nuovi ancoraggi in A4/316. Non credetegli, il costo superiore al 304/A2 è meno del 5% e spalmato negli anni con la naturale inflazione. Da quando tutti i produttori si sono spostati su questo materiale, il prezzo è molto sceso tanto da essere paragonabile al 304/A2.
Ci sono leggende che parlano di un pool tra le ditte per il non vendere ancoraggi in galvanizzato: non credetegli, non ci sono prove. La realtà dei fatti, è che solo un produttore ha continuato a fare galvanizzato (ora pare due) e se gli altri hanno abbandonato, un motivo lo avranno avuto.
Ci sono leggende metropolitane che parlano di obsolescenza programmata degli ancoraggi: più che parole, servirebbero fatti, ma i fatti io non li ho mai visti.
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cyclocaster



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MessaggioInviato: Mer Nov 02, 2016 5:35 pm    Oggetto: Rispondi citando

Kinobi ha scritto:
Se in una falesia in montagna la vita "tranquilla" della chiodatura è più di vent'anni, al mare si ragiona in un decennio.


Ciao, in che situazione collochi le falesie di Finale, Toirano; Albenga? Mi spiego: ad eccezione dei tiri di Capo Noli, che sono gli unici direttamente sul mare, le altre falesie liguri delle località che ho nominato, sono al massimo "vicine" al mare ( a volte qualche km di distanza e qualche centinaio di metri sopra il livello del mare ) ma non direttamente sul mare come alcune falesie di Sardegna, Sicilia e isole greche.
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Kinobi
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MessaggioInviato: Gio Nov 03, 2016 5:47 pm    Oggetto: Rispondi citando

cyclocaster ha scritto:
Kinobi ha scritto:
Se in una falesia in montagna la vita "tranquilla" della chiodatura è più di vent'anni, al mare si ragiona in un decennio.


Ciao, in che situazione collochi le falesie di Finale, Toirano; Albenga? Mi spiego: ad eccezione dei tiri di Capo Noli, che sono gli unici direttamente sul mare, le altre falesie liguri delle località che ho nominato, sono al massimo "vicine" al mare ( a volte qualche km di distanza e qualche centinaio di metri sopra il livello del mare ) ma non direttamente sul mare come alcune falesie di Sardegna, Sicilia e isole greche.


Il problema è che difficilmente ci sono parametri precisi.
Tipo di calcare, esposizione, correnti marine, ecc.

Per qual che ho visto io nella mia visita del natale scorso (o o forse due) sarei veramente molto estremamente sorpreso se ci fossero dei problemi in quale zona. Per tipo di roccia, angolo della roccia, e precedenti.
Ovvio, tra 15/20 anni ne riparliamo però.

E
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MessaggioInviato: Ven Gen 06, 2017 12:10 pm    Oggetto: Rispondi citando

Scusate l'inglese.
L'amico Jens di 8a.nu, mi ha richiesto per la 20 volta una riflessione sui problemi degli acciai inox al mare. O dei zincati al mare, o del titanio al mare. Gli ho fatto questa trafila per rifare il sunto di tutto. Se uno non capisce l'inglese, faccia copia incolla su google traduttore e il testo è ben comprensibile anche in italiano (controllato). Ovvero, non è perfetta la traduzione, ma chi vuole capire, capisce perfettamente.
In gamba,
E

Dear Jens,

the problem of corrosion of protections in marine environment has been widely discussed in past 8 years. In 2008 UIAA made a press release after serious accidents involving Petzl gear, which means the problem happened before. They advised climbers to be careful while climbing in ”tropical environments”. In that press release, there were photos of most brands.
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It was then edited in 2009.

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In 2012 both UIAA and Planetmountain.com made either a new press release, or an article, after the first accident happened in Sardinia (Biridiscottai and Masua) that involved gear of RAUMER. UIAA modified “tropical” with “marine” in their new press release.
In 2014 Michel Piola (one of the most known equippers in the world) brought to public the issue of corrosion in San Vito Lo Capo with a letter published by most web sites in the world. Even Petzl itself published in their web site the UIAA press release.

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There were many discussions from 2012 to today in social media, and the article “Built to last” published in Climbing.com makes a nice re cap of what has been discussed.

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Then in 2015 UIAA made another press release, published in two languages, which you also talked about, which bring up the problem even more. UIAA stated, “Climbers needs to start to pay for bolts”.

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It is an issue of material, rather than brand. Some brands are more prone to others, but can also be a simple “not super perfect” production batch”. I have personally pulled by hand some hangers last October in Ibiza. Contrarily to what some argue, even glue ins are not immune to this problem.
It is important to remember that climbing is a dangerous sport and climbers must place minimal care before, and during, climbing.

Rather than discussing the issue of material, which has been clearly and widely discussed in all the languages of the world, I try to give some guidelines for the climbers. It was already clearly explained by UIAA in their 2015 press release.

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Most of marine locations have been bolted with 304 (A2) stainless steel. Some areas are under rebolting either with 316 (A4) or other materials (titanium/Titan Climbing or duplex/ Fixe bolts products, or a treatment of 316/Raumer). Some still stays on 316.
While a zinc-plated hanger becomes rusted quickly, and therefore the level of rust define its strength (more rust means weaker), a stainless anchor looks ok, but can hold barely body weight. Given the scale of the rebolting needed, to expect all routes to be safe, we talk about a timeline of a decade and a lot of money. In some areas, more money is needed than probably the return from tourism.
The general rule is that grey rock, often is less aggressive to anchors, since the rain, once in a while, washes the protections. Yellow rock (overhangs) is where most problems occur. I personally see no difference between glue ins and bolts is strength and resistance to corrosion, while some believes glue ins are more resistant. Some rocks are more aggressive than others.
If a climber is not able to remember the handful shapes of hangers or glue ins used in the word, he/she should restrain from climbing in marine locations since he can’t judge if the route has been bolted recently, re bolted, and/or which gear has been used. In other words, “stay away if you can’t tell”. Big majority of climbers can’t tell, but they can study, since bolts producers are very few.
If a climber does not take the care while climbing to check the protection, he/she should restrain from climbing in marine locations. In fact, all “new” gear has marked the kind of material they are made from. Said before, to investigate the shape of hangers or glue ins, it’s a matter of less than a dozen shapes. Some brands have the year of production stamped. So, if a climber checks, he can understand the kind of material and with a guess when if was bolted.
Routes with chalk, at least, means that they have been climbed recently and therefore the protections “might” have been “tested” before which means “kind of ok”.
Most important of all: contribute, contribute, and contribute on rebolting. Open your valet to pay. If the climbing community as a whole, does not contribute, very likely we better stop climbing in marine location in many areas of the world.

A note of the materials used. 304 is lasting from 8 to 15 years in marine mediterrean (warm) locations with some exceptions. 316 should last 30% more. How long it will last zinc plated is a guess, from years to very long. How long it will last the resin (glue) they use in titanium or duplex it’s a guess since no supplier has certified the resin for these materials and neither will warranty for longer than 3 years.
So, each route that has been bolted more than 10 years ago, should be checked before committing to it. My opinion is that HCR expansion bolts are the best long term choice. Better than glue ins made from titanium/duplex.
My position in vesting money in rebolting with very expensive materilas has been expressed publically in this forum

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and here:

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@ Joshua: There is no interest to me to promote anything that it’s not working properly, because, as I wrote before, I am a climber and a bolt seller, but mainly a climber; there is a real chance that I get a whipper on a a bad bolt, so I am more concerned about safety rather than selling.
Marine: as far concerning my investigations, that can be wrong, there is a “bit of confusion” going on about the term “Marine”.
Example: “Marine” from a spanish supplier is 1,4404 (316L). “Marina” from an Italian supplier is 1,4404 with particular treatment, which according to them, will increase durability. The word “Marine” from me does not exist, but I sell 1,4404, which the Spanish supplier will sell and market it as “Marine”. What I told to Toni, and what I told to the people living in Kalymnos to shom I spoke with, and what I wrote before in this topic, is that there is no permanent solution in marine conditions. The bolts can stay in place, but resin might give up OR a whole piece of rock collapse in your face. What I am suggesting to anybody ask me what “I would do” is simple:
– Bolt with 1,4529 expansion bolts. M10. These should last +25 years anywhere. No chemicals/ glue ins.
– use hangers and belays in A4 (there is not real difference between 316 and 316L except hype), with stamped year or production/equipment, to be replaced/inspected each 10 years.
– Each 10 years, inspect the whole route for safety /rock).
I do not suggest 12 mm bolts, I have a few photos in my forum and I have explained (in Italian), why at the present stage using M12 bolts is a bad idea. Evidence of +25 years of falling, suggest me I am damn right.

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Best Regards
Emanuele Pellizzari

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