I am trying to find some information concerning cooling water requirements / specifications for resistance welding components (ideal flow, temperature, etc.). Also, I would like to find some information about closed loop resistance welding cooling water systems (ideal type of water - deionized, nonpotable, etc., chemical treatment - bacteria control, ideal conductivity, etc.). A manual or book of some kind would be most helpful. Thanks in advance for any help you can provide.

Fred Clark Specialist BW/PE-K Toyota Motor Mfg. Kentucky

-- Fred Clark (fclark@mail.tmmna.com), March 20, 2000

Answers

Fred,

Size: I know that there is some information about how to size chillers at: http://www.tjsnow.com/supplies/chiller.htm --but it involves measuring the ammount of heat you currently produce, and then sizing the chiller to match this. While I'm sure some guidelines exist, they are going to be very general. Think about it: Two identical machines running two vastly different parts will not put out the same amount of heat. So, any guidelines that you get, you will have to take as eduacted guesses until you go and measure how much heat you are putting off.

Flow: I would guess ~4 gal/min would be optimal for 3/4 in pipe, but have nothing to base this on besides Fluids class :) Mose chillers seem to come with built in pumps, so you don't have to worry about this too much.

Water / Water Treatment: Probably some standard treatment, similar to what you would put in a closed loop system for Hydronic heating systems. From what I understand you use standard water in these type systems-- the only thing that you might(??) have to worry about in the water would be air-- which could corrode the pipes over time. Conductivity is not a factor that you would need to increase or decrease from normal water.

Hopefully someone else can fill in the gaps that I have left. That is what this is for; helping each other.

-- Sam Snow (snowsam@eng.auburn.edu), March 20, 2000.

Unitrol did an AWS paper on this subject that was presented at two sheetmetal conferences. This paper compared different flow rates and temperatures against nugget tensile, electrode life, and nugget diameter. Work was done on crs and galvanized steel. If you want to get a copy of this study, just go to our web site (www.unitrol- electronics.com)and download the paper. If you have more questions, you can call me at 847-480-0115.

-- Roger Hirsch (roger@unitrol-electronics.com), November 16, 2001.