Fittings/line/channel size
 

Hey guys...

ok. There is a lot of talk about 1/2" and 3/8" 'fittings'

Now, does this mean, if the fittings are 1/2", the tubing would need to be 1/2" too? What about the waterblock? If the channels are only 3/8 deep, then wouldnt 1/2" tubing and fittings slow down the flow and possible add air to the system?

Is the purpose of using larger fittings to eliminate the reduction in flow into the rad etc... and the corner, so the 3/8" flow doesnt slow to change direction?

Are there 1/2" water blocks out there? or are people just using 1/2" tubing and fittings with a 3/8" waterblock?

should the rad be 3/8" piping, or 1/2"?

Also... How deep should the channels in a waterblock be? How thick should the block be? would having 1/2" deep waterblock channels and 1/2" rad pipes, and 1/2" tubing be better than all 3/8"?


thanks guys

Yan

OK! There are two measurements to a fitting. There is the tubing size. This is usually measured by the ID(Inner Diameter) of the tubing that is used with it. The other measurement is the thread size. This is usually reffered to as NPT.

Say you have a 3/8"ID x 1/4"NPT fitting. This means you would use a 3/8"ID hose and the threaded end would go into a 1/4"NPT threaded port.

Most of the people lately are going to a 1/2"ID tube, but the NPT thread is still the same.

ok...

If the ID (inside diameter) of the fitting is 1/2", then the ID of the tubing is 1/2", and the ID of the piping in the rad is 1/2" and the channels in the waterblock are 1/2" right?

Isnt the purpose of effective flow to have no restrictions or reductions in line size in the system?

thanks

Yan

Well....yes and no, their would be reasons to increase or decrease the size of the passages in some areas. for instance, inside the radiator you may want larger a larger path (or many small ones which add up to a larger one) to slow the flow down and give it more time to give up heat. In a chipset or GPU block you may want to go down in size to give more flow back to the processor because it generates more heat and needs more cooling...etc.

It is about designing a SYSTEM not just slapping together a bunch of parts...

If you are using barbed fittings, like those screwed on a pump or in a waterblock, 1/2" barb usually has an OD of slightly over 1/2" to mate with 1/2" ID hose (the hose has to go over it). The fittings with a 1/2" barb have a maximum of about a 3/8" path threw them in 3/8" NPT or larger, and nearly a 1/4" path threw them in 1/4" NPT (the threaded side)

Waterblocks such as the new "upgrade" Danger Den Maze 2 1/2" have a 3/8" path threw them, and 3/8" ID in the fittings. Basically if you have a well set-up 1/2" system, your fittings should all be a minimum of 3/8" inside.

This isn't always the case, it has been well brought to my attention that the older maze's and many other waterblocks on the market although using 1/2" barbs are only using 1/4" NPT (with approximately 1/4" ID) fittings! In my opinion this, and the fact that there channels are only nearly 1/4" would for the most part defeat the purpose of using 1/2".

Flow is constant. If your measured flow is say 60 gph, this figure will be constant at any point in the system. Velocity however will be greater in a thinner section and slower in a thicker section. Changing this velocity in theory has an effect in the cooling performance of the system, where higher velocity is assumed to help the waterblock, and a lower velocity allows more heat to leave the water in the rad. I'm not entirely sure about this, but I'm sure someone else can explain it without starting another argument :). In my opinion I wouldn't use a waterblock which was restrictive, again 3/8" path if your using 1/2" or 1/4" or larger if your usinf 3/8" hose. As for the rad, the theory of slower is better could well prove why my AC core was 5 degrees worse than a Big Momma style heater core with multiple large paths and tonnes of surface area.

Restriction is exponential with flow rate, so one or two fittings in say 1/4" ID (1/4" NPT) will reduce the flow almost as much as five or ten.

Basically if your setting up a 1/2" system you would like nothing to be less than 3/8" ID. If it's a 3/8" system, nothing smaller than 1/4" ID would be desired.

You can make up for slower flow with a bigger pump, but the reason to go with larger fittings for me is so I don't require a large pump, which in turn will heat the water and creat more noise. Now that I've installed a heater core style rad with my 1/2" and Maze 2 "upgrade" I think I would be better with a 250 gph pump than the 350 I have. When I was still using a AC style "Cube" the 350 did seem to perform better.

For the ultimate system check out BladeRunner's AN fittings!!! They have a constant ID threw the fittings and the hose, and in this case 3/8" would outperform 1/2" as the constant changes in ID of barbs again restrict flow. Expensive though!!!

They arent that expensive :) The ones I have cost less than a barb with a hose clamp.

Hmmm... I'll be checking the site then, I remember a friend replaced all his lines in his car with braided and AeroQuip AN, it was crazy expensize. But, if it's not that bad at least I could go to a smaller line and even improve the flow a bit (with more room to boot)!!!

Yeah I've got a jegs catalog right here, those are WAY more than mine run. Like I said in the other topic though, I'm not trying to sell them in here. It's just I used them WAY before I started selling them, and really I believe they do work better :)

I was just looking at LiquidCool.Org and couldn't find anything about AN fittings, just the push-in stuff....you did mention something about some new radiators on the page, any word on when there will be more details (especially on the BIG one)?

Yes I can give you some pics right now if you want. My ICQ is 95735580 and yahoo is liquidcool_org.
http://liquidcool.org/misc/radiator/image6.jpg http://liquidcool.org/misc/radiator/image7.jpg http://liquidcool.org/misc/radiator/image8.jpg

Those are 120mm fans on it. in the last 2 pics it looks like they dont fit. but the cooling area on the rad is EXACTLY 240mm, they fit PERFECTLY :) I also have mounting tabs added to all four corners, that was one of the problems I kept hearing was "How the hell do I mount this thing!" If you look in the pics you see the empty space next to the tanks. I placed a tab in that area for bolting it down. All I have to do is get a good way to mount the fittings and I'll have some fresh pics up. Should be by weds night. Most likely will just solder a bung on.

And whats wrong with my fittings? :) Simple to use, leak free, and cheap!