Nitrile Rubber for Caustic

[swall]

I have a spray washer on a paint line which is sealed at the top with rubber strip material to allow the parts hangers to pass through. The caustic cleaner (spray) is 4% sodium hydroxide at 140F.How well will nitrile hold up under this environment? I tried EPDM, but the oil coming off the parts swelled the rubber strip to the point that they scalloped and no longer sealed in the washer spray.

 

[sean01]

Swall,

I personally wouldn't try nitrile in this environment - preferring one of the Flurocardon grades (A,B,C Generic) available from DuPont.

If you are worried about its long term performance - why not bet a test beaker of the solution and leave a nitrile part in there ? If you want to get an accelerated life test - you could even heat it up

Sean

 

[swall]

Sean01--I probably will do some testing. It is easy task to cut some rubber coupons from the various materials and wire them to the grating on the washer floor. At this point, the hot mist leakage through the EPDM strips seems to have stabilized.The scallops of the mating halves have nested, so the rubber at least partially seals things.

 

[swall]

I just competed a 4 week test with a nitrile coupon. It exhibited a weight gain of 19% and a length increase of 2.5%. Since I have 50 feet of nitrile strip on hand, I plan to install it, but keep on testing other rubber types.