Nozzle life is a tough one to predict accurately because of the many variabilities such as the vast range of abrasive, their size, their shape, their hardness, varying air pressure at the nozzle, nozzle bore size and mouth diameter vs. hose I.D. at countless measurements during blast hose life, methods of abrasive cut-off or machine shut-down, and a slough of others.
Blast nozzle life is rated by its “Relative Wear Life” (RWL) which is based on its properties and material make up. The blast nozzle life chart illustrates the wear test results conducted by the U.S. Department of Interior and U.C. Berkeley to establish RWL ratings.