The Challenge:

A potential problem with a standard AAR-1 manway gasket is that the conventional design has to be precisely made with tight tolerances to fit snugly into a dovetailed groove so that it remains in place once installed. When this does not happen the potential for NARs is heightened. The required tolerances for these conventional style gaskets are difficult to achieve, and create quite a bit of scrap during the manufacturing process. In addition, if the ID is too small, installation becomes difficult if not impossible. On the other hand, if the ID is too large the gasket will easily fall out of the groove and into the manway nozzle. The result of this happening will cause leaks, splashes, and other releases from an improperly secured manway cover.