Pro/Forums

Pro/Forums (http://forums.procooling.com/vbb/index.php)
-   General Liquid/Water Cooling Discussion (http://forums.procooling.com/vbb/forumdisplay.php?f=9)
-   -   reducing iwaki pump inlet/outlet (http://forums.procooling.com/vbb/showthread.php?t=5399)

BillA 01-23-2003 10:37 AM

NICE link pHaestus
almost a complete listing of things ignored in WCing

ahh Ben, so near and yet so far - eh ?

Skulemate 01-23-2003 03:32 PM

pHaestus

Thanks, but I really have no use for it anymore, as I've recently upgraded to a motherboard that has a diode reader (of sorts). I do appreciate your offer though (and your remembering ;) ).

Blackeagle 01-28-2003 09:24 PM

How's it coming along?

m3_arun 01-28-2003 09:55 PM

if youre talking about the barbs.... i still have to make the trip to home depot to pick up those barbs. icouldn't find the right ones at McMaster.

im planning on 3/4FPTx5/8"barb.

the actual internal diameter of the inlet/outlet on the pump is exactly 1/2".

i dont really have resources/skill to make an inlet reservoir.

Blackeagle 01-29-2003 01:31 AM

I think what BillA was try'n to tell you is that the inlet, which has weak suction, benifits from larger lines as they offer less friction/resistence to the water. In other words have the water piled up on the inlet side waiting to get in. Which is exactly what a set up with a large 1 1/2" line (res) that reduces to 3/4" only at the last moment will give you. A 3/4" FNPT & 3/4" barb with a 3/4" line to minimumize resistences some would help out your pump and requires no modding/building skills. I'd use braided or copper line to insure no collapse or kink problems over time.

BigBen uses 3/4" lines on his Little Giant pump for best performance, and that pump isn't as powerfull as a MD30-rlz. Might want to PM BigBen and ask how much better his performance is with 3/4" vs. 5/8".

Blackeagle 01-29-2003 01:40 AM

I double checked McMaster and I made a mistake when I told you they were on the 1st page under barbed tube fittings.

They are in fact on the 3rd page of the barbed tube fittings area.

Sorry for the error.

bigben2k 01-29-2003 09:40 AM

Hardware stores don't usually carry those threaded barbs, in 1/8 increments, at least not in my area.

As for the McMaster part, it's# 5372K218 (nylon). (3/4 FNPT by 5/8 barb). They don't seem to have the brass equivalent.

I can't comment on 3/4 vs 5/8, but I can on 3/4 vs 1/2, to a certain extent: it depends on the flow you achieve. I was hoping to get to 4 gpm, but I was over-optimistic. At that flow rate, 3/4 ID tubing would have been a necessity, otherwise the tubing would be a significant restriction within the whole loop.

At 3 gpm, 1/2 tubing will have a pressure drop equivalent to 0.2 inches of head. 3/4 will drop 0.07 inch. This is all for 1 inch of length of tube (!).

At 2 gpm, 1/2 tubing will have a pressure drop equivalent to 0.1 inches of head. 3/4 will drop 0.01 inch.

At 1 gpm, 1/2 tubing will have a pressure drop equivalent to 0.03 inches of head. 3/4 will drop 0.004 inch.

These were calculated using the Hazen-Williams formulae, and as I found out recently, it may not be accurate at all.

:shrug:

Skulemate 01-29-2003 12:29 PM

Sure they carry them Ben (3/4" NPTF x 5/8" Hose in Brass). I just bought a package of those myself... the key is to look under "Pipe to Hose Adapter," not "Pipe to Tube Adapeter." The part number is: 91465K411.

Blackeagle 01-29-2003 02:00 PM

BigBen,

How high a flow did you get with the 3/4" lines? And what are the specs on your Little Giant?

Skulmate,

Thanks, I'd missed those.

Skulemate 01-29-2003 02:08 PM

No problem. As I said before, they match the ID of the connections on my 20-RZT pretty much perfectly, though that may not be the case for the 30-RZT.

bigben2k 01-29-2003 02:32 PM

Quote:

Originally posted by Blackeagle
BigBen,

How high a flow did you get with the 3/4" lines? And what are the specs on your Little Giant?

Skulmate,

Thanks, I'd missed those.

I'm still working on the block, and I don't have a pressure drop calculation, yet... sorry.

m3_arun 01-29-2003 03:14 PM

ok. thanks for the part number.

Quote:

they match the ID of the connections on my 20-RZT pretty much perfectly, though that may not be the case for the 30-RZT.
yah they match the ID of the 30rlzt too. im actually going to use 1/2" tubing, because, as bigben2k pointed out, the pressure drop is not so significant as compared with 3/4" tubing. cathar calculated the flow to be about 2.5gpm in my system.

BillA 01-29-2003 03:39 PM

you guys are fools

you thinking Iwaki put 3/4"NPT connections so you should run 1/2" lines ?

pHaestus wrote an article with an excellent link,
I put up some graphs, others have posted . . . .

"but a man hears what he wants to hear, and disregards the rest"

bah, pearls before swine

bigben2k 01-29-2003 03:54 PM

Bill's right.

What you really want to do, is use 3/4 tubing for the connection to the pump inlet. The rest of your tubing can be 1/2.

This is based on allowing the water to enter the pump unrestricted, at a lower velocity. The fitting alone is *apparently* not enough.:shrug:

Skulemate 01-29-2003 04:40 PM

Bill

Iwaki also makes a variation of the MD-20-RZT with 5/8" hose barbs rather than 3/4" NPT fittings... perhaps they are the fools? I am simply following the recommendation of their sales rep with my choice to go with 5/8" barbs and hose all around.

BillA 01-29-2003 05:36 PM

there are 2 somewhat different situations here (if I understand):

- a 20-RZT with 5/8" lines
- a 30-RZT with 1/2" lines

anything suggested there ?
one can drop the pump's head wherever desired,
but the only cooling to be derived from such is IN THE WB

now a 20-RZT in a WCing system is pretty extreme (though I consider it a 'good' choice)
while a 30-RZT is quite beyond any actual benefit, and will add a considerable heat load to the rad

but BOTH these pumps, and the consequent expense of same, would seem to justify (necessitate even ??) paying attention to ALL the details
- and OPTIMIZING everything possible
-> because if the flow rate is not 'reasonable', you're gonna be heating the water big time

there was a pretty good 20+ page thread on pump heating from a couple of years ago on the hard forums, but they wiped it out
- you might chew on this one. its related though actually about pressure
http://forum.oc-forums.com/vb/showth...hreadid=142006

just to repeat: any inlet restriction is unwise
with a high $ pump, its stupid

m3_arun 01-29-2003 09:56 PM

ok. i guess i'll go with a 3/4"FPTx3/4"barb for the inlet. the problem is i dont have a 5/8x5/8x3/4 Y piece... gonna have to find one of those.

Blackeagle 01-31-2003 12:19 AM

BillA's referanced disscussion found.
 
I found that thread that BillA mentioned. Go to the overclockers site and in their articles area under watercooling is a article called.

Water cooling flow rate and heat transfer

Only a one page article, but at the bottom it gives a link to the thread that BillA refered to above. Very good stuff, I spent close to 2 hours reading & rereading.

edit:

That link is to a thread at O/C forums, not [H], so I guess it isn't the one BillA mentioned, but sill a extreamly good read.

m3_arun 02-04-2003 11:38 PM

what do you think of running a full 3/4" system (except for the block). would that be good? would i still need to worry about inlet restriction? the only problem im facing in that case is the block, which has 1/2" fittings

BillA 02-04-2003 11:44 PM

if you get your lines too large you will not have enough velocity to clear them of air
5/8" is more than adaquate (and quite overkill for a 'normal' pump)

m3_arun 02-04-2003 11:45 PM

even for a md30rz?

BillA 02-04-2003 11:47 PM

5/8" will be fine

m3_arun 02-04-2003 11:48 PM

ok... so should i use 3/4" barbs with 5/8" tube? that would be better than 5/8" barbs right?

BillA 02-05-2003 12:04 AM

sure

m3_arun 02-05-2003 12:06 AM

do you know any place that sells a 5/8x5/8x3/4 y piece?


All times are GMT -5. The time now is 05:08 PM.

Powered by vBulletin® Version 3.7.4
Copyright ©2000 - 2025, Jelsoft Enterprises Ltd.
(C) 2005 ProCooling.com
If we in some way offend you, insult you or your people, screw your mom, beat up your dad, or poop on your porch... we're sorry... we were probably really drunk...
Oh and dont steal our content bitches! Don't give us a reason to pee in your open car window this summer...