2 replies to this topic

[babakfarhadi]

Hi Dear,
I start to building a new hobby scale linde cycle.I build a tubular heat exchanger with 1/4 inch ACR copper tube and 0.098 inch capillary tube inside 1/4.You can see pic on this link https://docs.google....M0diSE50b21FX0k

This is 12 turn on 8cm diameter wood.Gas enter from capillary tube and after EXPANSION back from volume between 1/4 and 0.098 .
Now i want build expansion device with hypodermic needle. brazing one end to capillary tube and other end to 1/4 inch.
I want know your idea and Experience about this project.

Best Regard
Babak Farhadi

[Art Montemayor]

Babak:

I like your challenge. I liquefied and distilled a lot of air in my time. I believe you are going in the right direction to put together a Linde air liquefaction and distillation cycle.

However, be aware that you are going to need a lot of copper tubing to make you final heat exchanger. Also be aware that you will need some machining and soldering capability or services in order to make your expansion valve. You need to make an extended expansion valve stem in order to be able to operate the device – which will be necessary as you adjust the expansion rate.

Be also aware that you must maintain and ensure immaculate and absolutely grease, and oils away from all wetted components – during fabrication and afterwards. You cannot afford to have even your skin oils on internal parts since the process is one where oxygen is concentrated. Any oxygen that comes in contact with grease or hydrocarbons, will explode.

You will also need a CO2 and water removal process ahead of your heat exchanger.

[babakfarhadi]

Hi Dear montemayor

Thank you for your reply.
First i want show my new job.
https://docs.google....OFZPSlZ5ZkFPMGc
https://docs.google....QjBzc29HSDhQck0
https://docs.google....RDA1Qm5KTkFWSEU
https://docs.google....SC1XY1ZuRllpa1E
https://docs.google....VXVXSGhsM1p6d1U
https://docs.google....b3czeTZVZ0hXTlE

On this pic you can see capillary tube braze to hypodermic needle and other side of neddle braze to 1/4 in tube this is expansion device.I want start this project with nitrogen 99.9 % without any water or steam.I want insulated heat exchanger and expansion device in foam.
Now i want know your suggestion about brazing , expansion device , heat exchanger , gas mediume and insulation.

Best Regard
Babak Farhadi