That's a valid point. SK75 doesn't conduct heat very well, though. So say there's a section touching a hot section of metal, the heat given off by that metal will only travel about 2/3 through the section being effected. Not even 1 full rope diameter.
Aramid rope vs Amsteel Blue vs "Plasma"
- Thread starter katuah
- Start date
That's a valid point. SK75 doesn't conduct heat very well, though. So say there's a section touching a hot section of metal, the heat given off by that metal will only travel about 2/3 through the section being effected. Not even 1 full rope diameter.
bfdiesel
Explorer
Ok. If the whole front of the truck reaches 140-180 it may. Radiant and conducted heat will saturate. I am not saying it will happen but I wear gloves to handle wrenches that have sat in the sun and you can cook eggs on on my hood in the summer without the engine running. Would be nice to see real world info from someone down around death valley, or arizona/new mexico desert.
I will probably stick with wire rope just because it is cheaper and I have yet to need to change it.
katuah
Adventurer
I'd really like to know how much of this article (linked earlier): http://www.plasmarope.com.au/plasma-vs-dyneema.html is marketing hype and how much is true:
"During the course of a research program into the life of ropes in towage operations in the US, it was discovered that ropes made from Dyneema can suffer from drum compression damage, that is damage caused to the rope while it is stored on the winch drum. This is basically a fatigue mechanism that sees the rope strength degrade over time from being stored on a winch drum. This would appear to diminish the effectiveness of these types of ropes in 4x4 winching applications. Compression testing results indicate that Plasma would have a 30% longer life in these sorts of applications."
The article also seems to indicate that Plasma/Spectra has better internal abrasion resistance than Dyneema/Amsteel Blue. If the UV resistance and other factors are essentially the same between the two, it would appear that Plasma is the better choice than Dyneema.
Anyone have any more data on plasma/spectra vs dyneema?
Technora/Aramid is now out of the picture due to the bending fatigue/sheeve diameter and lack of UV resistance. I still don't like the temperature fatigue ratings on the HMPE types, but I can mitigate temperature increases, I can't mitigate the size of the winch drum or the shining of the sun.
"During the course of a research program into the life of ropes in towage operations in the US, it was discovered that ropes made from Dyneema can suffer from drum compression damage, that is damage caused to the rope while it is stored on the winch drum. This is basically a fatigue mechanism that sees the rope strength degrade over time from being stored on a winch drum. This would appear to diminish the effectiveness of these types of ropes in 4x4 winching applications. Compression testing results indicate that Plasma would have a 30% longer life in these sorts of applications."
The article also seems to indicate that Plasma/Spectra has better internal abrasion resistance than Dyneema/Amsteel Blue. If the UV resistance and other factors are essentially the same between the two, it would appear that Plasma is the better choice than Dyneema.
Anyone have any more data on plasma/spectra vs dyneema?
Technora/Aramid is now out of the picture due to the bending fatigue/sheeve diameter and lack of UV resistance. I still don't like the temperature fatigue ratings on the HMPE types, but I can mitigate temperature increases, I can't mitigate the size of the winch drum or the shining of the sun.
I'm certainly not trying to change anyones mind on the synthetic/wire rope debate. Both work well within their limitations.
Samson did some testing on SK75 in regards to heat effect on the fibers. You can read about it here.
I also realize that not every situation is static. It is my opinion, based on the research I have done, that heat effects on SK75 in the offroad market are overstated. Even within the 140-180 range, the rope will only lose roughly 10% of its strength.
One of the caveats about heat degradation is that it increases at a higher rate than the temperature.
Samson did some testing on SK75 in regards to heat effect on the fibers. You can read about it here.
I also realize that not every situation is static. It is my opinion, based on the research I have done, that heat effects on SK75 in the offroad market are overstated. Even within the 140-180 range, the rope will only lose roughly 10% of its strength.
One of the caveats about heat degradation is that it increases at a higher rate than the temperature.
Ill read more in a bit... But this caught my eye...
From Samsons product page for Amsteel Blue here
EDIT:
In regards to "drum compression." I would like to see the data.
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