PEEK Outgassing for Food Applications

Q: I have a food processing application that requires a polymer screw that can get hot – about 300F. My concern is outgassing in the heat that can contaminate the food chemicals. Is there something that will not outgas that can work for me?

A: For your application I would suggest a PEEK screw. It is usable to 500F – well within your range. Also PEEK screws have a V-0 flammability rating. They can be used in high temperatures with low smoke and toxic gas emission when exposed to flame. In addition, they are approved by the FDA, USDA, and 3A Dairy.

PEEK Polymer Screws for Sterilization Processes

Q:
I need a fastener that can withstand frequent sterilization processes at temps to around 400F. I would prefer a polymer if possible. Also the process is pharma related, so the screws would need to be non leaching and may be exposed to low concentrations of chemicals. Any ideas?

A:
For your process, I would recommend PEEK screws. They are an economic solution and will meet all your criteria. PEEK fasteners are usable and strong to 500F. They are often used in pharmaceutical processes for their high purity and are approved by the FDA, USDA, NSF and USP Class VI medical grades are available. PEEK is also ideal for sterilization processes as it is able to withstand various processes including high doses of ionizing radiation. It is also hydrolysis resistance meaning it is resistant to water or steam at high temperatures and pressures- which occurs often in sterilization. PEEK fasteners being resistant to many chemical and temperature stable, this would be a good choice.

PEEK Screw Strength vs FDA Approved PTFE Screws

Q: I work in the food industry and need a larger sized polymer fastener sized 1/4-20 x 2.5″. I tried PTFE but it isn’t does not seem to have enough strength. It also needs to be FDA approved and offer moderate corrosion resistance.

A: Not knowing the specific strength requirements of your application, I would suggest a PEEK fastener. PEEK screws are FDA approved and offers decent corrosion resistance. PEEK is also much higher strength than PTFE which will be important in a larger bolt. PTFE only can provide a yield strength of 1450 psi compared to PEEK screws which offer 13,600 psi in yield.