PU or Hyperlon Tubes which to go for?

tim cozens · 24 February 2004, 17:46

The new X-Ribs have PU collars, are there any disadvantages with these compared to the more usual Hyperlon ones ?

Pitkis · 24 February 2004, 18:50

I suppose you mean Hypalon tubes? Disadvantages of PU compared to Hypalon:

- PU can't stand wear as much as Hypalon
- PU is more sensitive to sunlight
- PU is more easily punctured
- In a along run PU tubes have to be replaced by Hypalon ones with high price...

Couple RIB builders (at least one T-named) are trying to convince that Hypalon is not the best material for tubes, but the truth is that there are no better choises for serious RIB use today. 1500 g/m3 Hypalon is used by military and the most demanding RIB users man can imagine. And they drive hard, really hard, so even heavy civil users can rely on Hypalon as their tube material very well. For absolute pleasure in sheltered waters PU might be a choise, but if you are going to drive at sea, don't think anything else than Hypalon.

DJL · 24 February 2004, 20:12

They both have their advantages and disadvantages; I don't think there is a definite answer.

In lab tests Polyurethane provides about four times the abrasion resistance compared to Hypalon (trademark name for Chlorosulfonated Polyethylene). Also the welded seams used in the construction of PU tubes are thought to be much stronger than glued PE tubes. Hypalon is dissolved by some aromatic and chlorinated hydrocarbons, such as benzene which exists in petrol.

On the other hand Hypalon has been tried and tested for years not only on RIBs but as a roofing material amongst other things.

Don't get mixed up with PVC and PU, PVC rots in the sun, PU doesn't, at least not anywhere near the same rate.

PU is used by the US Military, probably for its abrasion, tear and puncture resistance.

Pitkis · 24 February 2004, 21:33

US Military has a lot of Hypalon RIBs in use. For example NSW Rigid Inflatable Boat http://www.specialoperations.com/Navy/RIB/default.html has Hypalon tubes in every 140 boats delivered to US Navy. If PU is better, why Navy chose Hypalon for the most important boat they use? Didn't the engineer next door told to his colleague that PU is better? I don't think so. I would like to see more information, which RIBs are PU tubed in US Military since every major projects I have seen are fitted with Hypalon tubing.

I know Tornado delivers information that US Navy uses PU and it's obviously true in certain scale, but they still have more Hypalon RIBs in service in toughest missions.

DJL · 24 February 2004, 22:13

I believe it was around 1993 that the US navy decided that PU was to be adopted over Hypalon for navy RIBs. I have no idea whether they went ahead with the recomendations of the Naval Surface Warfare Center.

Pitkis · 25 February 2004, 21:55

Can you tell me, which RIBs in US Navy use PU tubes? I just liked to know as I have heard this PU-tube thing many times, but no one has never told me specific boat types. NSW Rigid Inflatable Boat was taken into service 1997-1998, so there really has been time to think carefully all experiences related tu tubes. Maybe US Navy went back to Hypalon after they tested PU in early 1990s? I'll ask when I see Navy buddies next time, but please tell more, if you have details.

Manos · 25 February 2004, 22:40

I've seen somewhere (either here or in a US forum) a comparative test between PVC (as PU) (something German) and Hypapalon (I think it was ORCA but I'm not sure) material.
The results were similar and all in all there was no difference at all in either material being resistance to heat, cold, oil, fuel etc.
PVC had a bad reputation in the past.
However modern PVC materials are as good as anything else. I believe that is a fashion in Europe that most of the tubes are made by hypalon and not PVC. Zodiak and Bombard use PVC and they are doing great!!

My boat's tubes are made out of PVC and so far have no problems with it.
May I suggest that when people make statements like this material or the other is no good it would be much better for all if they can substantiate what they say with facts. Otherwise there is no use on the info.
I will try and dig out this test. I think I have saved the file somewhere and post it.

robin · 25 February 2004, 22:49

I have been following your thread, I am looking for a Rib myself and happened to come across this in the on line ribmagazine. Was written by Paul Lemmer on this very subject...

http://www.ribmagazine.com/articles/...stbuylater.htm

Seems like a fairly good article. Worth a read. Has a bit half way down about Hypalon versus PU/PVC etc

DJL · 25 February 2004, 23:22

Manos, don't get confused between PVC (Poly Vinyl Chloride) and PU (Polyurethane - PUR). PVC is actually more closely related to Polyethylene, and therefore Hypalon than PU.

I would however agree that for the average user the materials used in the construction of the tubes really not need be considered. There are many more important features to consider.

Pitkis – I will try and dig up the info on the US Navy.

Edit: Zodiac seem to use a fabric called Strongan™ Duotex ™. I have no idea what this is made of.

Manos · 26 February 2004, 07:49

Quote:

Originally posted by DJL
Edit: Zodiac seem to use a fabric called Strongan™ Duotex ™. I have no idea what this is made of.

Isn't another (marketable) name for PVC?

paul tilley · 26 February 2004, 08:53

Hypalon is considered to be the best fabric for tubes due to its good all round properties ,it can give a very long life ,the oldest tube i have seen was 26yrs old and used regularly before needing retubing ihave never seen a PU or PVC tube last any where near that long , some pvc and pu tubes have been known to last less than 18 months .PVC and PU are both harder to glue than hypalon thus making them less user friendly when you need to do that little get you home repair .IT is also afact that in the uk especially most RIB builders are only relatively small and it would not be cost effective to buy the sort of equipment Tornado have to make their very nice looking welded PU tubes as most glued PU tubes seem to fall apart when the glue seems to crystalize . In my humble opinion the only thing PU has going for it is its better abrasion resistance but this is outweighed by the user friendlyness of hypalon . The UK MOD tried PU tubes but seem to be sticking to hypalon.

Manos · 26 February 2004, 09:07

Paul I just thought that PVC was easier to use than Hypalon. Does not need the same amount of preparation and glues very quickly. Learn something every day here

jwalker · 26 February 2004, 12:57

Quote:

Originally posted by paul tilley
seem to be sticking to hypalon.

Ho, ho.

roywebster · 26 February 2004, 21:39

The rib that I am have on order (Ribeye 6m playtime) has tubes made from Hypatex. I understand from Ribeye that Hypatex is PVC based has anybody any experience of this material.

Roy

Manos · 27 February 2004, 07:54

I was told by someone who uses PVC instead of Hypalon on RIBs that if they used hypalon instead of PVC the price of the RIB would have increased by 45%.
Is this correct?

Pitkis · 29 February 2004, 18:13

Well, price of the basic boat without equipment and engine might go up quite well if Hypalon is used instead of PVC. Still, you have to note that during RIB lifetime of, say, 20 years, PVC tubes have to be replaced several times, but original Hypalon tubes can work the whole lifespan without problems.

Manos · 11 March 2004, 15:17

Just found those comments about Hypalon and PVC and thought that you may be interested to know:

PVC Advantages
Lower manufacturing cost i.e. lower product cost
Easier to repair & glue
Wider variety of colours
Can be double-skined with Rhino Hide to withstand vigorous scuffing and abrasion ..... especially useful in full commercial boats.
Lighter i.e. race boats (less weight = more speed)

HYPALON Advantages
Immensly strong
Wear resistant
Waterproof and air tight
Immune to hazards of sunlight, ozone fuel, oil, acids and contaminants.
A boat with Hypalon Tubes has a better resale value.

ribraff · 11 March 2004, 15:27

....sorry Manos, i disagree on the PVC being easier to repair.

Manos · 11 March 2004, 15:41

I was shown how PVC is repaired when I was in South Africa and have to say that I am completely useless with all that but even I can do it. And if I can do it must be easy.

Clean both surfaces with acetone or similar product, mix the glue with hardener, apply thin layer on both surfaces, let it dry completely, warm it up very little with a hair dryer and glue it. If you made a mistake and before is completely set you can pull it apart and re stick it. I think is very simple my self. When is dried about 4 hours is ready to be used and since hardener has been mixed in the glue it will NEVER split.

But as I said I’m not an expert so I may be wrong

swginn · 11 March 2004, 16:55

Since this thread is about PU (polyurethane) vs Hypalon, I just thought i'd point out that Polyurethane is not PVC.

The only similarity is that both fabrics can be heat welded. PVC is an unstable polymer because of the chemical make up of the fabrics coating. This means that the PVC fabric is constantly changing, oxidizing and migrating to the surface. PVC's are liquefied with solvents where polyurethane is liquefied by heat, leading to a significantly more stable fabric coating. Stories about tubes rotting in the sun are about PVC - not polyurethane.

I think you'll find that a read of the following web page should shed some light on the issue:

http://www.wing.com/polyurethane.html

Note the US Navy test at the end of the page which recommends that hypalon ribs should be replaced with polyurethane tubes. I don't think this caught on with the US Navy, probably preferring to stick with old fashioned glue instead of welded seams.