Valve commonly used standard code

CVA - Valve Association Standard BS - British National Standards EJ - Nuclear Industry Standards JIS - Japanese Industrial Standards YB - Metallurgical Standards DIN - German Standards HG HGJ - Chemical Standards ASTM - American Materials Testing Council Standard Q / TH-a machine chemical general machinery professional standards API - American Petroleum Institute standards DF - high pressure helium valve design standards MSS - American Valve Association standards GB - national standards ISO - international standards JB - Machinery Standard ANSI - American Standard SY - Oil Standard NF - French Standard DL - Department of Energy Machinery