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MikeHolm
28-01-2013, 02:42 PM
I have some brazed plate HE and they came without distributors. The ports are too big and I want to reduce flash gas. Has anyone made them and if so, do you have a diagram?

Thanks

Rob White
28-01-2013, 05:07 PM
I have some brazed plate HE and they came without distributors. The ports are too big and I want to reduce flash gas. Has anyone made them and if so, do you have a diagram?

Thanks


I'm confused Mike? (I know, I know it doesn't take much :D )
I thought Brazed plate heat exchangers only had one entry and one exit
(refrigeration side) so how would a distributor after the expansion valve
fit?

Or am I being realy dense now :o

Rgards

Rob

.

MikeHolm
28-01-2013, 08:40 PM
In my case, the port size is 1- 3/8" and it goes right to the back of the HX( of course). The liquid line in this case is a 3/8" so there is a large area for the refrigerant to flash so i want to reduce that volume if possible. The distributor needs to be an elongated liquid line that goes right to the back of the HX like a manifold to try and give equal flow and take up some of the volume at the same time.

I've done this many times but not in a BPHE so i was wondering if there was a particular way they were built to reduce the open volume.

Brian_UK
28-01-2013, 11:25 PM
Any chance of getting a distributor from the HE makers?

MikeHolm
28-01-2013, 11:52 PM
Stupidly, I already brazed in the reducer before I thought about the distributor. I'm sure i can make it but a picture would be nice.

mikeref
29-01-2013, 06:33 AM
Mike. How about taking a picture or 2 of your Heat exchanger so we can see what you're trying to achieve.;)

hookster
29-01-2013, 07:04 AM
Hi Mike
FYI as i am no expert on your question but it intrigued me!
http://www.google.com/patents/US5806586

The drawings are useful for the description of operation, although I would never advocate commercially producing unlicensed patents, we leave that for certain global producing companies.

hope it helps

Rob White
29-01-2013, 08:10 AM
.

So I was being dense ;)

I see your point and Hookster's solution seems a good one but you have
brazed in a reducer already. What size have you reduced it down to?

Regards

Rob

.

MikeHolm
29-01-2013, 12:21 PM
.

So I was being dense ;)

I see your point and Hookster's solution seems a good one but you have
brazed in a reducer already. What size have you reduced it down to?

Regards

Rob

.

1-3/8" port down to 3/8". It leaves a BIG area inside. Seeing the patent drawing, cut off the reducer and I can make a brass one that will fit inside the bigger part of the reducer. Not very pretty but doable. My mentor suggested I turn the holes down or sideways, rather than up, to move the refrigerant that sits at the bottom.

Magoo
29-01-2013, 11:54 PM
Hi Mike.
the BPHX's I have used come with an injector type tube with a linear laser cut slot that acts as the distributor, they have an alignment marking so as to feed circuits correctly. Slide it in, align and weld in place.

MikeHolm
29-01-2013, 11:58 PM
Hi Mike.
the BPHX's I have used come with an injector type tube with a linear laser cut slot that acts as the distributor, they have an alignment marking so as to feed circuits correctly. Slide it in, align and weld in place.

Do you have a link to them?

Magoo
30-01-2013, 12:05 AM
WTT out of Germany.

mad fridgie
31-01-2013, 07:30 AM
Install a liquid line/suction line h/e, fit the TEV bulb after the h/e, this will reduce the flash gas a basically flood the bottom port.

MikeHolm
31-01-2013, 11:18 AM
Install a liquid line/suction line h/e, fit the TEV bulb after the h/e, this will reduce the flash gas a basically flood the bottom port.

The liquid from the condenser goes through a short "tube in tube" HE on the comp suction line, then to the pancake coil in the accumulator, then through a subcooling valve, then to the Evap which is on the same level as the valve. The bulb is on the line entering the "tube in tube HX". There is nothing between the comp and the condenser inlet. I should have at least 10-15C subcooling prior to the evap (BL50 30plate HE) and it is designed to be partially flooded.

I was told that Alfa laval had trouble years ago in highly subcooled evaps with out distributors, freezing out one side of the HX and splitting it. I just want to get equal flow and I am not sure that there will be any real flash in this design but I could be surprised.

Mad, where you have placed the TEV?

MikeHolm
31-01-2013, 11:57 AM
WTT out of Germany.

Just finding general links. Time to phone manufacturers.