MSS SP-80-2008
This MSS Standard Practice establishesrequirements for bronze gate, globe, angle, andcheck valves in Classes 125 (PN 20), 150, 200,300 (PN 50) and 350 for threaded and solderends and Classes 150 (PN 20) and 300 (PN 50)for flanged ends. Pressures in this StandardPractice are gauge pressure in pounds persquare inch (Kilopascals). Hereafter thepressure will appear as psi (kPa).