Another rough calculation is that a 6 lb bag of party ice will take 864btu to melt in a cooler. so depending on your velocity through air piping in the cooler it may have about as much/more energy removal then the bar fridge over a couple hours of cut time
similar amount of energy as running the harbor freight dryer for 1.5 hours.
I would pack the cooler with ice and fill will salted ice water for max heat transfer.
Another expansion of the bar fridge idea ( @DnKFab which is a great diy dryer idea btw) would be using a small chest freezer with a copper tube heat exchanger inside then filling the freezer with antifreeze. the heat transfer rate would be many time higher then air to air heat exchanging while also having a greater delta T.
This setup will likely be able to do longer cutting times then the bar fridge. but with a extreme long cut sessions 6-8-10 hours range you will likely needed to move back to a standard refrigerated air dryer.
Very true, but if the refrigerator has trouble keeping up with the desired cooling, the frozen bottles would easily buy additional “cooling credits.” But if the heat exchange gets the internal temperature of the refrigerator warmer than the point the refrigerator would normally cool, then the warmed water bottles would be a liability (same with just water bottles stored in the frig).
In the case of the refrigerator warming up with time, one could say that would likely happening even with more insulation or without the water bottles.
I do like the antifreeze idea for the better transfer of heat. But adds a messy element.
Have you done the math to see how much cooling the air needs for the plasma cutter to keep going without a moisture issue? The hypertherm 45xp manual calls for a minimum of 6 CFM at 90 psi.
These commercial air dryers are made to pull the water out of high CFM items, like paint sprayers and sandblasters.
As an aside, the water bottles in my fridge are there as a convenience factor since I have the room to keep drink water cool in my fab trailer. If I’m getting extra benefit from the cold water assisting with keeping the internal temperature down then yay.
I wasn’t trying to knock the bar refrigerator set up, it seems like a very decent inexpensive setup for shorter cutting sessions in favorable ambient temperature and humidity conditions. I was just trying to add a little context to the conversation.
Refrigerated air dryers are built to deal with the CFM range and ambient conditions they’re designed for whether that’s high or low. And all these dryers have a very specific operating range( inlet temperature and CFM). Some are designed for 6 CFM some are designed for 9 CFM some are designed for a 100 CFM. One thing refrigerated air dryers do all have in common is they are specifically designed to take thermal energy away from Air in the most efficient way possible. (DX to air exchanger)
I have . Mind you you only can take a look at it as a snapshot in time because throughout the year it varies wildly. When designing your system that allow for it running in summer on a high humidity day with a high ambient temperature while also considering the longest session you have on that day. That hypertherm 6 CFM is a minimum and they also specify an air quality standard. Here’s a post more about the air quality standard that hypertherm requires.
Definitely the water bottles help extend the session time with your setup.
My assessment of the bar fridge scenario obviously rubbed you the wrong way.
Here is a good question.
If a bar fridge with coil of Copper in it does the same job as a small six or nine CFM refrigerated air dryer, why is there not a company making these for quarter or 1/5 the price of a standard refrigerated air dryer and flooding the market?
No, not at all - just adding on to the AI comment from above. @TinWhisperer is smart…he knows things…This is why a lot of us ask you a lot of questions and seek your help and advice.
The only way I can think of to test and verify is to out a temp sensor inside an airline and find a way to sample for humidity at the termination point after x number of time running.
Before and After real world use in 90* ambient, 90% humidity and my compressor with it’s inherent heat generation of the air after exceeding the recommend duty cycle is night and day.
SO - $?$ on copper tubing attached to the wall, with or without a transmission cooler in front of a fan on the low end, Redneck air dryer in the current conversation timeline as a mid $$$ DIY, or pony up and spend the money on an actual air dryer rated for expected use plus 15%.
@TinWhisperer as our resident bot I think you are going to have to get used to others addressing you as deity. Just one more step down the path…. You have now reached the status of Mindar in Kyoto, Japan and the Bless You Too Bot in Germany.
No doubt!!! But with the current climate of distrust, it is doubtful that the machines would be totally autonomous as there will always be a greedy consortium of people that will be benefitting and have a back door of influence on the machines.
And, after-all: If someone is smart enough to build a machine that could replicate, learn and be autonomous…they are also smart enough to know that they could eventually be on the receiving end of something they might not like.
I have been thinking about a turbo between the compressor and tank… wonder if that would keep the pressure in the head down so I can add a after cooler.
