_RP_550-2-1977_scan.pdf

API RP 550MANUALONINSTALLATION OF REFINERY INSTRUMENTSAND CONTROL SYSTEMSPART II-PROCESS STREAM ANALYZERS22.323AMEFOREWORDThis manual is based on the accumulated knowledge and experience of engineersin the petroleum industry.Its purpose is to aid in the installation of the moregenerally used measuring and control instruments and related accessories in orderto achieve safe,continuous.accurate,and efficient operation with minimum main-tenance.Although the information contained herein has been prepared primarilyfor petroleum refineries,much of it is applicable without change in chemical plants,gasoline plants,and similar installations.This third edition of Part II of the manual,represents the latest suggested orgenerally used practices in the installation of all the devices covered in the secondedition plus additional information based on revisions suggested by many indi-viduals and several organizations.(The first edition of the manual was issued in1960.the second edition in 1965Users of this manual are reminded that in the rapidly advancing field of instru-mentation no publication of this type can be complete,nor can any written docu-ment be substituted for qualified engineering analysis.Certain instruments are not covered herein because of their very specializednature and limited use.When one of these devices(or classes of devices)gainsgeneral usage and installation reaches a fair degree of standardization,this manualwill be revised to incorporate such additional information.Suggested revisions are invited and should be submitted to the director of theRefining Department,American Petroleum Institute,2101 L Street,N.W.Wash-ington,D.C.20037.进