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vives120
30-04-2006, 04:04 AM
Hello i need help to know is there is like a relation (optimal) ship between the tons of refrigeration that I am taking out of a industrial system and de diameter and length of the pipe.<?xml:namespace prefix = o ns = "urn:schemas-microsoft-com:office:office" /><o:p></o:p>

wambat
30-04-2006, 07:29 AM
In a word "Yes" for more on this I recommend this:
http://www.climaticcontrol.com/info/jjzgate/Infotec/Info-Tecs11-20/Infotec_12(rev1).htm

Peter_1
30-04-2006, 07:33 AM
IT depends also on the gass you use, the evaporating temperature,...

The MG Pony
30-04-2006, 08:04 AM
where can I download thees charts that will print well on a dot matrix?

Peter_1
30-04-2006, 08:11 AM
Download the free Danven program from Danfoss, do some easy calculations with the conditions you mostly use and write your results in a dot matrix you like.

The MG Pony
30-04-2006, 09:34 AM
Couldn't find it, could you post a link? It will be very much appreciated.

Peter_1
30-04-2006, 12:08 PM
http://www.danfoss.com/Asean/BusinessAreas/Refrigeration+and+Air+Conditioning/Product+Selection+Tools+Details/DIRcalc.htm

US Iceman
30-04-2006, 04:28 PM
Hello i need help to know is there is like a relation (optimal) ship between the tons of refrigeration that I am taking out of a industrial system and de diameter and length of the pipe.

In the IIAR Piping Handbook there is a procedure for estimating the pipe size based on an economic diameter. I believe you need to know the cost of electricity, capacity, and estimated pressure loss to do this.

In most cases, you are trying to minimize the pressure loss of the piping to minimize the impact on compressor performance.

Lower evaporating temperatures may require a lower pressure loss allowance than a high evaporating temperature.

One way of thinking about this is to use the equivalent saturation temperatures between both ends of the pipe. You want to minimize the temperature loss between components in the system.

At discharge pressures, the equivalent pressure loss for a 1 degree temperature loss is quite small. At low temperatures, the equivalent pressure loss for a 1 degree temperature loss can be very big.

The MG Pony
30-04-2006, 06:23 PM
I all ready treid DIRcalc, and did not find it easy to understand at all, I'd rather just good ol tables and a 90degree ruler, or at the very least a more understandable system thats more streight forward.

Peter_1
30-04-2006, 10:34 PM
You can't just use simple tables without understanding teh basiscs behind it.
Because you need to understand in what tabels you will have to look and if the results you found match the reality.

US Iceman
01-05-2006, 12:08 AM
Tables, charts, and software programs should only be used by someone who already understands refrigeration in my opinion.

It is too easy to become dependent on these without full recognizing the impact of the decision made when using the tables, charts, or software programs.

Software programs are the hardest to use because someone can input some data and the program simply provides an answer. If the person using the software does not know what answer to expect, he/she can make many problems.

The MG Pony
01-05-2006, 03:16 AM
Well I all ready built a R290 A/C, wasn't the best performing but it was my very first build, this one I'm doing properly based on gass volocity return oil and all that I'm mainly looking for the slide rule type charts to learn with while doing every thing. like my thread below, I was hoping my idea that the valve being close to the TXV was correct, sso I'm learning and I feel having the charts will help me get to the next basic level of understanding.

Andy
01-05-2006, 08:42 AM
Hi MG Pony:)

Propane is quite similar in properties to R22, except a thicker grade of mineral oil is used, minimun of 100 grade oil on high temperature systems.

The starting place would be a good quality R22 system, change the compressor oil and work from there.

Kind Regards. Andy:)