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DEVITG
07-07-2012, 03:49 PM
Hi all .

I need to find a vendor for a chamber to hold aircraft alumniun parts at -40C or -40F

It shall be 20 ft (6 meter)length, 10 Ft wide (3 meter) , 10 ft Heigth (3 meter), inside size.

It will have a double door 2 meter by 2.5 m height on a end.

and 2 windows , at each side 0.80 x 0.80 meter

Loading rate is about 100 kG once per hour , with doors full open .
Incoming temperature 40C , cool rate to reach -40C , 6 hours.
When the doors are opened , the temperature shall not be upraise to -35C .
Air curtain , and PVC stripe shall be install , both at doors and windows.
Double 100% compressor and evaporator , as to have 100% backup.
No pre chamber allowed , by site space
This chamber is to stop aluminium hardening after heat treatment, to keep it soft until further processing the parts.

Thanks in advance

Magoo
08-07-2012, 04:49 AM
look at liquid nitrogen spray system, cryogenics.

mad fridgie
08-07-2012, 09:18 AM
look at liquid nitrogen spray system, cryogenics.

To cold, magoo.

You can get thermal stress as droplets hit the metal.

I was building cryogenic metal cooling chambers, somewhat cooler -190C.

mad fridgie
08-07-2012, 09:21 AM
Hi all .

I need to find a vendor for a chamber to hold aircraft alumniun parts at -40C or -40F

It shall be 20 ft (6 meter)length, 10 Ft wide (3 meter) , 10 ft Heigth (3 meter), inside size.

It will have a double door 2 meter by 2.5 m height on a end.

and 2 windows , at each side 0.80 x 0.80 meter

Loading rate is about 100 kG once per hour , with doors full open .
Incoming temperature 40C , cool rate to reach -40C , 6 hours.
When the doors are opened , the temperature shall not be upraise to -35C .
Air curtain , and PVC stripe shall be install , both at doors and windows.
Double 100% compressor and evaporator , as to have 100% backup.
No pre chamber allowed , by site space
This chamber is to stop aluminium hardening after heat treatment, to keep it soft until further processing the parts.

Thanks in advance

It can be done with ease, your biggest question what deviation in temp can you have from -40C.

if you want -40C metal and average air temp, then the air being produced must be below -40C, then apart from opening what deviation can you go (upwards)

So basically the accuracy of control determines the type of system and then the cost of the system.

DEVITG
08-07-2012, 03:33 PM
The main fact is

When the doors are opened , the temperature shall not be upraise to -35C .


Then it must reach to -40C +/- 1C .

mad fridgie
09-07-2012, 12:29 AM
Very tight conditions.
Your issue is that the air change rate with such big doors and such a small area, mean that it will be difficult to achieve your requirements. Not impossible.
Initial thoughts would indicate that you will require 4 systems (100% back up), and that your would require considerable space external to the chamber (sides and top) (a meter or so) Superior air distribution and evenness of temperature.
I hope you have a good budget for the project.

DEVITG
09-07-2012, 01:35 AM
What do you think about air courtains from inside , and PVC strip ovelapping 50%.

My other concerns is about the door gasket and its heating method, as it is a double side opening.

It is specified to have 100% backup, I do not understand what do you mean by 4 systems.

Thanks for any help.

mad fridgie
09-07-2012, 02:44 AM
What do you think about air courtains from inside , and PVC strip ovelapping 50%.

My other concerns is about the door gasket and its heating method, as it is a double side opening.

It is specified to have 100% backup, I do not understand what do you mean by 4 systems.

Thanks for any help.

I think you need a dedicated low temp air curtain (*2) to basically reduce high temp air infiltration, and then a system (*2) for the load which is minimal and the load of the box iteslf. 4 system is total.

I would go for 2 air curtains, first just ambient, then second as stated above.

The plastic curtains, that does comes down to the product itself.

DEVITG
09-07-2012, 05:21 AM
Thanks .
Could you give me further details.?

mad fridgie
09-07-2012, 06:25 AM
Thanks .
Could you give me further details.?

There is not much i can give on the concept side.

The rest is all detail, and a lot more detail is required to confirm concept, then design.

My advice is to fully understand the loading/unloading process (and what you are loading).

You may be best employing a consultant.

I think you should get some change out of 1/4million US$

DEVITG
09-07-2012, 08:46 PM
Thanks for your's tips. That amount seem to reasonable .

forkliftaccess
05-08-2012, 03:59 PM
You can try to look at different online store (http://www.forkliftaccessories.com), they have the information that you need.

chilliwilly
05-08-2012, 11:12 PM
Try this firm http://www.keighleylabs.co.uk/ they're not a refrigeration company they're a metalurgical company and they may be able to offer another option.