![pub](/gifs/pub.png)
Metal finishing Q&As since 1989
-----
Need non-stick, food grade, permanent coating
Q. I am trying to control biological build-up (Fungi) on the inside of a 36" diameter X 92" high Stainless steel tank. We do not need to control the biological population, just stop it from coating the tank walls, because it falls off and causes a visual defect. Process fluid is soapy water at 85 °F and pH range from 2.5 - 8.0. A test piece of Teflon impregnation fabric worked fine, so now I need to treat the inner surfaces of the tank with a similar non-stick product. The Non-Stick coating must not flake off or leach into the process fluids. I like the Ni/Teflon electro-plating technology, but our tank is too large for the local plating shop.
Tony Willis- Pittsfield, Massachusetts
2003
A. Is the tank electropolished? If not, electropolishing the tank may solve the problem permanently because it will completely remove all "tooth".
![Ted Mooney, finishing.com](../portraits/ted_mooney_beach.jpg)
Ted Mooney, P.E.
Striving to live Aloha
finishing.com - Pine Beach, New Jersey
2003
Q. Electro-Polishing ? Didn't think of that. One possible problem, on some grades a mildly abrasive fiber will be in the fluid. Would this cause micro-scratches and destroy the polish finish ? Could try it with a small test plaque I suppose.
Tony Willis- Pittsfield, Massachusetts, USA
2003
A. Sorry, I can't really answer that. I can only say that electropolishing is routinely used in the pharmaceutical and food industries to remove the "tooth" from stainless steel to discourage stuff from sticking to it. Good luck.
![Ted Mooney, finishing.com](../portraits/ted_mooney_beach.jpg)
Ted Mooney, P.E.
Striving to live Aloha
finishing.com - Pine Beach, New Jersey
2003
A. This is a typical application for a Teflon Coating.
Jordi Pujol- Barcelona, SPAIN
2003
A. We line cold water storage tanks with polypropylene (flexible). In the past we used flexible PVC; on inspection a year later there was some bacterial build up, i.e., slime. We have now changed to Polypropylene and the results are the complete reverse. One year of no build up present; this may be worth a try.
Best regards,
M Brightmore- Doncaster, England
2003
A. Kiss-Cote from KissPolymers.com is a self bonding nano-silicone coating that will relieve your problem. Best of luck!
Bruce Dean- Central Point, Oregon
September 15, 2014
Q. Dear Sir,
My name is Hendra, now I do some research on metal coating, especially with Teflon for coating "food grade" candy mould, to make some nonstick mould to make candy. I need some information about the equipment and detailed process for make nonstick Teflon coating. And where I can get the raw material (e.g., the Teflon liquid or powder). Thank you for the information.
Best Regards,
Alfonsus Hendrawan, Mechanical EngineerGadjah Mada University GMU) - Yogyakarta, DIY, INDONESIA
2005
Q. Nanotechnology nonstick coating is food grade or not?
Khushal Patel- India
August 13, 2018
August 2018
A. Hi Khushal. Although 'nanotechnology' has a specific meaning and is an exciting field, the word neither implies that a product which employs it is foodsafe, nor implies that it isn't. In that sense it's kind of similar to asking whether grey non-stick coatings are foodsafe or not -- some are, some aren't.
Regards,
![pic of Ted Mooney](../portraits/ted_mooney3.jpg)
Ted Mooney, P.E. RET
Striving to live Aloha
finishing.com - Pine Beach, New Jersey
Q, A, or Comment on THIS thread -or- Start a NEW Thread