Ich schrieb die Autoren an:
Dear Sirs,
I am currently reading your Handbook, congratulation!
I tried to find any information in your book about a defined lifespan. In Europe all manufacturers have a limited lifespan of 10 years on textile products, some even less, even if the rope is not in use and stored well. They say it degradiates to an extent that it becomes dangerous – without providing evidence.
In my work I could prove that for Nylon ropes this is not the case.
So – my question: Is it true that you could not verify a maximum lifespan of Nylon Ropes if not in use or destroyed or worn?
... und bekam von Nick O'Hear folgende Antwort:
Dear Mr.Siebert
Thank you for your message.
Sadly Professor Hearle died a few years ago and Hank McKenna retired some 10 years ago.
As we all know it can be hard to prove a negative, that is there is no mechanism for degradation in a rope in storage.
In reality we calculate rope lifetime in terms of the prevailing wear mechanism such as tension-tension fatigue or creep rupture.
In storage of course there is little to degrade a rope. In some fibres there might be UV degradation or a possibility of rotting. Assuming the conditions of storage are good, these can be discounted, and the lifetime is presumably unlimited. In practice riser protection nets are designed to last 30 or more years and do so.
Fibre manufacturers will have more information.
I hope this helps a littlle.
Yours sincerely
Nick O'Hear
In einer folgenden Mail bekräftigte er die Wichtigkeit von Abnützung:
Good morning
I don't mind if you use my reply on your website.
There is also the opposite problem of ropes being used when they are very worn and dangerous. Ship mooring lines fail periodically and lash back. This occasionally causes injury and even death.
If you are going to recommend using ropes longer, I hope you would draw attention to the danger of not retiring ropes when they are worn.
Kind regards
Nick O'Hear
Nun, ich empfehle nicht, Seile länger als im Manual angegeben zu verwenden.
Das sind - je nach Hersteller - zwischen 3 und 10 Jahren, teilweise bis 15 Jahren.
Ich konnte bisher einen einzigen Hersteller in Europa finden, der keine maximale Lebensdauer angibt: Tractel.
Quelle: https://www.tractel.com/en/product-applications/harness-range
Ich stelle Forschungsergebnisse zur Verfügung und hoffe, dass die maximale Lebensdauer aus den Manualen verschwindet. Die Hersteller haben es in ihrer Hand.
