Teflon coating or alternative

[DYV1973]

LS,

We are applying a teflon coating (PTFE / FEP) to a stainless steel surface for its non-stick properties. Problem is that in some occasions the coating lets loose.

- Is there a method to test the bonding of the teflon coating to the stainless steel?

- Is there an alternative for teflon as a non-stick coating, that can be used up to approx. 250 C

- What method can be used to test non-stick properties of a coating (fluids will be eg. crude oils etc).

thanks,
DYV

 

[KENAT]

Not a direct answer but something that came up on a project I'm working.

Is the stainless properly cleaned before the ptfe coating is applied?

Posting guidelines faq731-376

http://eng-tips.com/market.cfm?

(probably not aimed specifically at you)
What is Engineering anyway: faq1088-1484​

 

[DYV1973]

The stainless is blasted with grit powder and heated (to clean) up to approx. 400 C.

DYV

 

[unclesyd]

Is this for cookware or is it for an industrial service?

 

[DYV1973]

It is industrial service (eg crude oils), for sensor parts that are in piping systems.

 

[unclesyd]

Here are two possibilities for your service as defined, Ryton from Chevron Phillips and a Phenolic coating from Heresite. There are so many variations in materials, cleaning, application, and curing I would definately give a call to the application engineers at each company.
I have used phenolic coatings and Ryton coatings and parts with very good success in some very aggressive environments.

http://www.cpchem.com/bl/rytonpps/en-us/Pages/default.aspx

http://www.heresite.com/products.php

In our cleaning procedure for parts to be coated and/or cured we run them through a Pyrolysis Oven prior to grit blasting or any additional surface modification. We are getting rid of the organics first so we don't cover any organics up have have problems later, both during and after curing.

 

[dragracer9]

the problem with teflon is it does not stick to anything very well and it requires a bonding agent. its this agent you need to inspect.

tungsten disulphid may be an alternative. it can take the head better than the teflon and does not require a bonding agent. also an inert material so your safe with the oil. just make sure to use a company with a good rep so its applied properly.