Polyurethane Gasket

It's a gasket made from polyurethane, or at least the wetted surfaces are polyurethane. Presumably it is used in your plant because whatever it is in contact with will corrode or melt natural rubber, so the answer is superior heat and corrosion resistance compared to natural rubber for that specific application.

More resistant to tears and impact maybe being use where seal is under a lot of stress due to vibration.

I worked in a factory that made glass fibre radomes for use on submarines, these were approx. four metres long by two metres wide and elliptical in shape, they had bolts pitched every few inches (that were screwed into steel which had been glassed into the body) so as to make a water tight joint,the joint face was then covered in a liquid gasket substance which may have been polyurethane, and a corresponding steel mating face was positioned on to this face and tightened to a predetermined figure, then left until the joint material set, then the plate was removed, the radome was then ready for fitting. without the need for any further gasket.

Polyurethanes can be selected to have superior compression set and are also more resistant than many elastomers to ozone attack.

There are numerous factors. Please visit.... here.... if there is any concern of corrosion.

cr3

where have I been? Does any one know I went missing. Were the authorities notified? Tsk, Tsk, woe is me!