这两处的service如何理解?(关于PID说明)? 1. show line designation of major process and utilities lines including service symbol , line number, size, spec, insulation requirement. service symbol :是指介质代号(如:ev ,n等) 2. process data required for completion of instrument datasheets of control valve, flow meter, analyzer etc. safety relief data indicating process services (not including utilities, fire case, etc) . process services :是指工艺介质查看更多