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-----Need to buy a copper sulphate kit for testing cleanliness of steel
Q. I need to find a source for purchasing a copper sulphate
⇦ on
eBay or
Amazon [affil link] test kit for testing mild steel plates after washing to determine if and how clean they are.
Thank you.
parts washing and shot blasting - Guelph, Ontario, Canada
2006
Ed. note: This RFQ is outdated, but technical replies are welcome, and readers are encouraged to post their own RFQs. But no public commercial suggestions please ( huh? why?).
A. The solutions for copper sulphate testing are typically made up IN HOUSE with sulfuric Acid and copper sulphate crystals
These items are readily available
If you require the details and concentration of the make up of solution please let me know.
Regards,
Peter
- Charlotte, North Carolina, USA
July 18, 2013
Q. Is the copper sulphate test applicable to determining residual oil film on parts? My experience is mostly as a metalworking guy, rather than metal finishing. I want to determine the cleanliness of steel parts after being produced using two different metalworking fluids. Would the copper sulphate test be applicable for this? Is it a qualitative, or quantitative test?
Any other recommendations? Thanks for your help.
- Shelby, North Carolina, USA
September 20, 2013
A. Hi Nathaniel. I'm not quite sure what you mean by "cleanliness" in this context because any surface that has a film of metalworking fluid on it is not clean.
Metal finishing people often use the super-simple waterbreak test for cleanliness: Dip the part in water, and it will form a continuous sheet if clean, whereas it will bead and break if dirty. I think any and all surfaces which last saw a metalworking fluid will be hydrophobic and will break, but I'd be happy to learn something. Good luck.
Regards,
Ted Mooney, P.E.
Striving to live Aloha
finishing.com - Pine Beach, New Jersey
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September 26, 2013
Q. Hi Ted. Thank you for the response. I agree with your assertion regarding the cleanliness of surfaces last contacted by metalworking fluids. I need a method to quantify, or clearly show that the part surface is "cleaner" when using one fluid versus another. The customer is currently using a traditional soluble oil product which leaves a noticeable oil film on the parts after machining. After machining, the parts are sent through a burn-off oven to remove this (I do not know why this method is preferred over washing). My company's product is formulated with ester and emulsifiers designed to run cleaner rather than carry-off on parts, chips, conveyors, etc. The product can in fact be washed off with water only. The problem is that the customer is not sure the oven will remove the ester oil as effectively at the same operating temperature, but they have no way to test the cleanliness of their parts. This is where I need help. I considered washing the parts with solvent and subsequent filtration (weighing filters, etc.), but I'm not sure this is the best way to go. I need something accurate and repeatable.
Nathaniel Ledford- Shelby, North Carolina, USA
September 30, 2013
A. I do not care what the oil is, burning it off is a bad idea as it leaves a tightly bound ash that the plater has to be very aggressive with to get off. Some oils actually forms an organo-metallic which is extremely hard to get off.
I would hope that they would use a vapor degreaser.
There is no way to prove your claim with a method that can not be gamed. figures do not lie, but liars figure.
- Navarre, Florida
October 1, 2013
A. Various mixtures of copper sulphate are used for a lot of different things, though the application I am most familiar with is as an indicator of free iron on the surface of something. Most often used to check passivation on stainless steel or the integrity of a coating (electroplate or otherwise) over carbon steel. I don't think it's applicable to Nathaniel's issue.
As for the actual question at hand, "cleanliness" can mean a lot of different things. If the simple stuff like water break doesn't satisfy, then you have to start getting into methods such as washing the part with a liquid known to be able to dissolve the suspected contaminant, and then collect that fluid and have it analyzed using an appropriate test method.
This tends to result from institutionalized paranoia, for instance if everybody knows the part is clean but "proof" is required because the red tape says so. In the given example the customer should just perform the water rinse that is known to remove your product and then send it through the oven to dry, rather than trying to figure out if the oven will burn off your product. Good luck convincing them of that, though.
Ray Kremer
Stellar Solutions, Inc.
McHenry, Illinois
October 8, 2013
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