Consider the advantages of PCD bearings.  Diamond is widely recognized as the hardest known material for unparalleled abrasion resistance.  These bearings exhibit very low wear rates, even in the dirtiest, most abrasive operating environments.  Furthermore, PCD bearings are tough, with fracture toughness much higher than tungsten carbide or silicon carbide.  This extreme resistance is combined with excellent thermal conductivity, high load capacity, and a low coefficient of friction to make an ideal bearing material. 

US Synthetic bearings can be used in temperatures from cryogenic to over 400 C in nearly any process chemical.  The bearings do not require external flush or outside lubrication beyond the process fluid itself.