It give the number of contaminants in the oil sample that is use in hydarulic machine or in equipment. For a Turbine( oil used - servoprime 32) the NAS number must be less than 10 micron in 100 mili liters. read more
NAS 1638 became a standard not only for the aerospace industry but also throughout many other industries as well. The latest version of NAS 1638 is SAE 4059. Nevertheless, in many areas of industry, NAS 1638 has largely been outpaced by the ISO 4406 standard in recent years. read more