Why is my tubing gradually turning into oval shaped?

wasserkool · 02-10-2006, 08:30 PM

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..

MaxxxRacer · 02-10-2006, 08:50 PM

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

btw is that right before the pump?

situman · 02-10-2006, 08:58 PM

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.

wasserkool · 02-10-2006, 09:02 PM

Quote:

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?

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..

wasserkool · 02-10-2006, 09:15 PM

Quote:

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?

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?

MaxxxRacer · 02-10-2006, 10:14 PM

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.

Mr. Tinker · 02-10-2006, 10:25 PM

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

trance565 · 02-10-2006, 10:34 PM

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

MaxxxRacer · 02-11-2006, 02:19 AM

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.

UnreaL · 02-11-2006, 05:18 AM

Quote:

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?

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.

RMSwins · 02-11-2006, 10:02 AM

Quote:

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.

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.

creidiki · 02-11-2006, 10:30 AM

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.

mindwreck · 02-11-2006, 11:15 AM

Quote:

Originally Posted by Mr. Tinker

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

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.

RMSwins · 02-11-2006, 11:25 AM

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.

RMSwins · 02-11-2006, 11:28 AM

Quote:

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.

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

creidiki · 02-11-2006, 12:22 PM

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?

MaxxxRacer · 02-11-2006, 02:12 PM

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.

Hassan · 02-11-2006, 02:40 PM

hehe you said donkey poo

RMSwins · 02-11-2006, 02:42 PM

Quote:

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.

.... 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.

~~KaptCrunch~~ · 02-11-2006, 02:45 PM

Quote:

Originally Posted by RMSwins

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.

BS baffles brains.....but mine fell out long ago

bottom line all substances with heat weaken. note any plastic has a memory of heat cycle when manufactard was flat then blown round in jig/mold so when reheated trys to go back to orginale forum

Bloody_Sorcerer · 02-11-2006, 02:46 PM

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.

~~KaptCrunch~~ · 02-11-2006, 03:22 PM

another note RMSwins what does Cavitation have to do with hoses flatting

MaxxxRacer · 02-11-2006, 04:11 PM

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.

Quote:

Originally Posted by RMStwins

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

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.

Semper Fi · 02-11-2006, 04:58 PM

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.

Zenjirou · 02-11-2006, 05:02 PM

Maybe coolsleeves might save you trouble of replacing tubing.