Yes, that does make sense of the observations. After one trial without cleaning, I cleaned the rings with a volatile solvent and they felt quite grippy afterwards. My guess is that there was still oils/waxes inside the nitrile that allowed it to slip.
Thanks.
They're square rubber rings, normally used for sanitary fittings.
I don't want to add a taper as I think this would jam the rubber spacers and inhibit further adjustment.
The rubber is tight on the tube with 0.05-0.1mm clearance on diameter in the housing.
I was thinking that at the force...
I'm trying to use HNBR (Nitrile 70 Shore A) as a kind of stationary gland packing - at the same time holding and sealing a 304 SS tube (Bright 320 grit polish finish). I've made a test rig - see pictures below. But when I apply the load of 6000N, the tube slips. There doesn't seem to be a...
