Why is my tubing gradually turning into oval shaped?

This is really weird, when I first setup my watercooling loop all the tubings are round and now when I open my case and take a look at them, the tubings are gradually getting more oval in shape.. It is not kinking or whatever, but it is just getting flatter and flatter..

what could be the cause be? I am using 1/4 inch tubing with compression and push-in fitting.

The pic below shows what I mean:
http://img156.imageshack.us/img156/4367/oval1ic.jpg

the tubing was round at first and gradually its getting more oval...and it worries me because it might cut off the flow to the system..

What the hell.. is that at a bend or is it going straight and getting flat?

btw is that right before the pump?

might be a clog somewhere? Its like if you suck on a straw while covering the other end of it with ur finger the straw will collapse.

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Originally Posted by MaxxxRacer

What the hell.. is that at a bend or is it going straight and getting flat?

btw is that right before the pump?

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It is a small bend and the top tube goes to the inlet of the pump and the bottom tube goes to the outlet...

I don't think there is any blockage in the tubes..

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Originally Posted by MaxxxRacer

What the hell.. is that at a bend or is it going straight and getting flat?

btw is that right before the pump?

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the top tubing goes to the inlet of the pump and bottom goes to the outlet and there is no bends at all..

I think its pressure of the pump collapsing the tubing? Will this cause leaks in the future thou?

the suction of the pump is collapsing the tubing. I suggest you get bigger tuing. That straw sized 1/4" tubing is rediculous and is starving the pump.

It also looks like your tubing is twisted right there at the kink.

i dont think the suction of the pump is collapsing teh dubing, doesnt make sense to me.

it's pushing water through the tubing, at teh same rate it's pulling it in, there fore there really isnt any suction of that sort to cause collapsing of the tube(so long as the water is being placed back into the tubing it wont do that). the only way i could think of it doing that, is if there is a clog in either
A) pump outlet
or
B) in one of the blocks

trance, the collapsing of the tubing is a common problem with stronger pumps. If you read the Iwaki manuals you will see that they specifically say you should make sure to avoid this at all costs.

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Originally Posted by wasserkool

the top tubing goes to the inlet of the pump and bottom goes to the outlet and there is no bends at all..

I think its pressure of the pump collapsing the tubing? Will this cause leaks in the future thou?

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That pretty much confirms Maxxx's comment, basically the pump accelerates the water out of the outlet, leaving a vacuum at the inlet causing the tubing to crush in on itself..

Simple solution would be to reduce volts going to your pump with a fan controller.

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Originally Posted by MaxxxRacer

trance, the collapsing of the tubing is a common problem with stronger pumps. If you read the Iwaki manuals you will see that they specifically say you should make sure to avoid this at all costs.

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No.... sorry, but just plain no. These watercooling systems are all zero pressure environments, hence the reason why you can bleed the system without having to seal the reservoir. Trance565 is right. The tubing may be collapsing due to a localized blockage. A normal hose without blockage on a strong pump would not collapse due to the uniform suction on the walls of the tubing. The inward force on the tubing walls counteracts each other and prevents collapsing. Blockages usually create microscopic low pressure zones against specific parts of the tubing walls. (edit) This is all assuming you are using the same ID tubing as the stock barbs on the pump and that you are not using extremely thin walled tubing.

In an ideal world where your tubing is perfectly circular and the forces on it are equal on all its surface.

In the real world, with imperfect production and bent turbing under torsional forces and already subject to kinking, the pump will quite happily collapse the tubing on the intake side, if the tubing is small enough/pump is powerful enough.

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Originally Posted by Mr. Tinker

It also looks like your tubing is twisted right there at the kink.

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thats whats happening. it happend to me when i first started wcing. I was using some cheap 5/8"OD 1/2 ID tubing. The thin wall and the twisting causes it to eventually flatten.

True. Torsional forces would also be amplified in a pressurized system due to the compression characteristics of water and air. Yet in a non-pressurized system there is no air compression and minimal water compression, thus the actual fluid would attempt to equalize itself. Again, because this is a non-pressurized system, a major blockage would TEND to create air bubbles due to turbulance. These are not absolutes (as some people ALWAYS tend to talk in) and I do see your point.

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Originally Posted by mindwreck

thats whats happening. it happend to me when i first started wcing. I was using some cheap 5/8"OD 1/2 ID tubing. The thin wall and the twisting causes it to eventually flatten.

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That makes more sense considering belted garden hoses exhibit the same characteristics when the actual hose becomes twisted.

Well, its everything together. A WC loop is not properly equalised, because the blocks cause quite a lot of restriction, and the tubes are elastic.

So the tubing right after the outlet is under quite a lot of pressure and expands elastically, while the intake tube is actually at a negative pressure compared to the average liquid pressure in the loop. After all, pressure differential is how the water moves in the loop.

Couple that with the tubes being naturally bent and hence not as resistant to pressure as a true cylinder, plus thin walls if you have cheap tubing and heat softening them up... well, you know when you suck fruit juice really hard through a cheap straw?

Please ignore RMS.. He generaly spews bull.

I will fully respond to the thread later, but suffce to say what RMS is saying is a load of donkey poo.

:eek: hehe you said donkey poo

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Originally Posted by MaxxxRacer

Please ignore RMS.. He generaly spews bull.

I will fully respond to the thread later, but suffce to say what RMS is saying is a load of donkey poo.

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.... and this coming from someone who just regurgitates rhetoric whenever he is proven wrong. Nice show of maturity, looks like you can't handle what you regularly dish out.

no, it's coming from the moderator of the liquid cooling forums who also happens to be an expert in the field of liquid cooling and all things related. not to mention he's right and you're wrong.

RMS, scrol down to section 8.12 of this PDF file.

http://www.iwakiwalchem.com/iwaki/Li...D/RDmanual.pdf

After reading that you will see that you were completely wrong.

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Originally Posted by RMStwins

Nice show of maturity, looks like you can't handle what you regularly dish out.

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I am merely tired of people telling others things that are completley false when they have absolutley no basis for saying them. You tend to do this with nearly every post that I see you put on XS, and it is rather rediculous. If you dont know what you are taking about, just dont say anything. Your statements are based on pure conjecture, rather than any personal experiences, or knowledge from technical documents. In this particular case, I ahve both personal experience and knowledge from the aforementioned Iwaki document.

wow... complete lesson in ownage?

Anyways... just by looking at that picture, you can see the tubing is twisted.... twist any tubing you have laying around, even a few degrees and it collapses on itself. If I were you, before I ripped my loop apart, turn off everything and just twist the tubing in the opposite direction (which would be clockwise judging by the pic) at either side of that collapse.

edit: sorry I should have said counterclockwise. The tubing looks like its twisted clockwise.

Maybe coolsleeves might save you trouble of replacing tubing.
http://cooltechnica.com/Merchant2/gr...eves02-350.jpg

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Originally Posted by MaxxxRacer

RMS, scrol down to section 8.12 of this PDF file.

http://www.iwakiwalchem.com/iwaki/Li...D/RDmanual.pdf

After reading that you will see that you were completely wrong.


I am merely tired of people telling others things that are completley false when they have absolutley no basis for saying them. You tend to do this with nearly every post that I see you put on XS, and it is rather rediculous. If you dont know what you are taking about, just dont say anything. Your statements are based on pure conjecture, rather than any personal experiences, or knowledge from technical documents. In this particular case, I ahve both personal experience and knowledge from the aforementioned Iwaki document.

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Well at least you didn't ban me before I posted my overclocks.

No one is going to ban you for saying things that arnt true. Other forums may do this but we dont

How about that ALL OF YOU ARE WRONG.

http://forums.procooling.com/vbb/sho...28&postcount=7

interesting explanation nik, but that would only happen if you had the system REALLY sealed up at every piont, and most of us dont have our systems that sealed up.

I have had this happen to me, as soon as I took the cap off my tee line the tubes rounded out again.

I can't say I've ever had this happen to me before, but then again this also stresses the importance of good tubing.

Masterkleer 1/2"id 13/16"od is almost impossible to kink, check it out :)

Edit: Of course this will require you to completely redo your watercooling loop with new blocks and all but what the hell right? lol....

nik, all I can say is that you have a very well sealed system. lol.

maxx, what?
if the tee-line is plugged or the res is capped it is a closed loop

if you think that closing your t-line/res makes it perfectly airtight...

well...it IS watertight, eh?

oh wait, then how do you explain fluid loss over time?
it's been discussed at procooling for a little while now, and the culprit is the tubing.

airtight is a such an indefinite term in this case...but yeah, for all intents and purposes, a closed system is airtight.

Snowwie, Id like to think my system is air tight, but its not. Its alot eaiser to get a better sealed system with a T-line than a res so long as you use a hose barb plug on the T-line.

Anyway, we all know that the water can evaporate through the tubing, which leads one to t he logical conclusion, if water molecules can make their way through tygon, so can air molecules.

so you are saying a negative pressure difference is impossible to achieve in a our loops?

realize there is a difference between semi-permeability and permeability. a closed water loop is NOT permeable (neither air nor water goes in or out freely), although the tubing commonly used in our loops is at some level semi-permeable. at some level.

I can attest that my loops have negative pressure after a while, getting my res open is a nightmare unless i let some air in first. In this case, with a pretty young loop, i would look elsewhere for an explanation though.

Maxx your "conclusion" looks more like an assumption to me. Several materials (many of which are made from polymers like tubing) are used for permeateive (hope that's a real word) properties to certain molecules while being non-permeative to others.

Crunch your example was meant to explain my negative pressure? If so, the coolant is filled in at ambient pressure, and even applies when loop is still hot, i only ever noticed it after several months, not after a fresh installation/refill.

Snowwie, what Im saying is that the tubing is semi-permeable. If you read the tech docs on Tygon, they even state as such.

Tygon R3603
"The permeability for CO2 is such that if the tube wall is 1 mm thick, and the pressure across it is 1 cm of mercury, then you will lose about 2.5 x 10^-6 millilitres per second through each square centimetre of tube wall."

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Originally Posted by snowwie

so you are saying a negative pressure difference is impossible to achieve in a our loops?

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Is that a question posed to me? If so, what exactly are you asking me? Are you asking If I am saying that our loops cant have a lower ATM than the outside air? Most surely they can if the system is perfectly sealed and the sum of the permeability of all the materials in the loop (with respect to surface area and thickness) is greater for H2O than it is for air.

maxxx, that's the wrong answer. the right answer is it IS possible, because it happens (read niksub's post). Therefore, a closed watercooling loop is airtight.

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Originally Posted by snowwie

maxxx, that's the wrong answer. the right answer is it IS possible, because it happens (read niksub's post). Therefore, a closed watercooling loop is airtight.

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Thats faulty logic right there mate. Cars crash when it rains, but that dont mean that ALL cars crash as soon as there's some water on the road.

nik's isn't an isolated incident, look at the original topic of this thread. the fact is that over time, water will evaporate through the tubing. now maxx is saying this wouldn't cause negative pressure in the loop because a) closed loops aren't airtight and b) even if they were, the fact that water vapor could evaporate through the tubing is testament to the fact that air/gas can freely move through the tubing thus equalizing any pressure differentials. his explanation for why nik and many others experience neg. pressure in their loop is that they "have a very well sealed system" and it's not typical. I have issue with his response is all.

lol snowwie. Your putting words in my mouth.

I didnt say taht ALL closed loops arnt airtight and I didnt say that ALL closed loops could not create negative pressure in the loop.

I also never said that air/gas can move freely. I said that it can move through the tubing and it is a known fact, that Saint-Gobain Performance Plastics Corporation has documented themselves. The rates at which air and water are permeable is different.

I also stand by my statement that most people do not have very well sealed system (to use my own words). I see many people using batteries, DD Fill caps, etc for their T-lines. Such "devices" will lead to a system that is not 100% sealed.

creidiki also pointed out the same fault in your logic.

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Originally Posted by MaxxxRacer

I see many people using batteries, DD Fill caps, etc for their T-lines. Such "devices" will lead to a system that is not 100% sealed.

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Im using the sawed-off spindle part of a 100-cd spindle... fits nice :D

well jeez maxx, it looks like you owe RMS a bit of an apology, eh

Its best to use 'could be', rather than 'is', its saved me looking like a munter several times

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the suction of the pump is collapsing the tubing. I suggest you get bigger tuing. That straw sized 1/4" tubing is rediculous and is starving the pump.

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How do I owe RMS an apology?

as to my use of the world is, I humbly appologize as I could not and do not know for 100% that the suction of the pump is cuasing the collapse of the tubing.

I'd also like to note that Wasser hasnt returned with any feedback on our suggestions, so none of us know who is indeed actually correct.

To quote RMS

"(edit) This is all assuming you are using the same ID tubing as the stock barbs on the pump and that you are not using extremely thin walled tubing."

Notice that the pdf that you linked to suggests using hose the 'same size as the inlet and outlet', so you completely shot yourself in the foot, by ripping the :banana::banana::banana::banana: out of him, then proving his point... Seems like you have a personal beef more than anything.

My Iwaki sucked tubing flat when I tested it in a open system (sucking water out of a sink. However, when I put it in a closed loop, the pressure from the pump was enough to push the tubing round near the pump inlet.

There may be a difference in pressure between the pump outlet and inlet, but I don't think that in a closed, small loop that differential is enough to suck a tube flat.

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Originally Posted by Mr. Tinker

There may be a difference in pressure between the pump outlet and inlet, but I don't think that in a closed, small loop that differential is enough to suck a tube flat.

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Depends entirely on your tubing... how flexible and elastic it is, and how thick its walls are.

Tinker the dp between the inlet and outlet in a closed loop will be the same (for the most part anyway) as in your sink so long as the flowrates are the same.

The diference is the negative pressure on the pump intake will be lower in a closed loop.

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Originally Posted by Etacovda

To quote RMS

"(edit) This is all assuming you are using the same ID tubing as the stock barbs on the pump and that you are not using extremely thin walled tubing."

Notice that the pdf that you linked to suggests using hose the 'same size as the inlet and outlet', so you completely shot yourself in the foot, by ripping the :banana::banana::banana::banana: out of him, then proving his point... Seems like you have a personal beef more than anything.

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I concur.

Honestly, looks like your tubing is just badly positioned and twisted.