Nitrile rubber (NBR) can become stiffer and lose flexibility as temperatures fall. For sealing applications, the important question is not simply whether NBR hardens, but whether a specific compound can retain sufficient elasticity and sealing contact under the actual operating conditions.

Choosing between a Y-type seal and an O-ring requires more than comparing their cross-sectional shapes. The right choice depends on whether the seal operates under static or dynamic conditions, how pressure acts on the sealing element, and whether the material and groove design suit the working environment.