_RP_550-1-4-1980_scan.pdf

Manual on Installation of RefineryInstruments and Control SystemsPart I-Process Instrumentation and ControlSection 4-PressureAPI RECOMMENDED PRACTICE 550FOURTH EDITION,FEBRUARY 1980春GNERLIBRARY29 JUN 1982gHRECEIVEDlIp hdatc aAmerican Petroleum Institute1A42101 L Street,NorthwestWashington,D.C.20037ACCN0,3035Manual on Installation of RefineryInstruments and Control SystemsPart I-Process Instrumentation and ControlSection 4-PressureRefining DepartmentAPI RECOMMENDED PRACTICE 550FOURTH EDITION,FEBRUARY 1980OFFICIAL PUBLICATIONREG.US PATENT OFFICEAPI recommended practices are published as an aid to standardization of methods andprocedures.These recommended practices are not intended to inhibit the use of practicesother than those of API nor to inhibit the purchase or production of products made tospecifications other than API.Nothing contained in any API recommended practice is to be construed as granting anyright,by implication or otherwise,for the manufacture,sale,or use in connection withany method,apparatus,or product covered by letters patent nor as insuring anyoneagainst liability for infringement of letters patent.API recommended practices may be used by anyone desiring to do so.Every effort hasbeen made by the Institute to assure the accuracy and reliability of the data contained inthem;however,the Institute makes no representation,warranty,or guarantee in connec-tion with the publication of API recommended practices.The Institute hereby expresslydisclaims any liability or responsibility for loss or damage resulting from their use;for theviolation of any federal,state,or municipal regulation with which an API recommended!practice may conflict;or for the infringement of any patent resulting from the use of an!API recommended practice.Copyright 1980 American Petroleum InstituteFOREWORDThis recommended practice is based on the accumulated knowledge and experience ofengineers in the petroleum industry.Its purpose is to aid in the installation of the moregenerally used measuring,control,and analytical instruments;transmission systems:andrelated accessories to achieve safe,continuous,accurate,and efficient operation withminimum maintenance.Although the information contained has been prepared primarilyfor use in petroleum refineries,much of it is applicable without change in chemicalplants,gasoline plants,and similar installationsSuccessful instrumentation depends upon a workable arrangement which incorporatesthe simplest systems and devices that will satisfy specific requirements.Sufficientschedules,drawings,sketches,and other data should be provided to enable the construc-tor to install the equipment in the desired manner.Various industry codes and standards aswell as laws and rules of regulating bodies should be followed where applicableFor maximum plant personnel safety,transmission systems are used to eliminate thepiping of hydrocarbons,acids,and other hazardous or noxious materials to instruments incontrol rooms.Proper installation is essential to use fully the capabilities that are builtinto the instrument or transmission system.When installing an instrument,various components must be accessible for efficientmaintenance,and certain of these elements must be readable for good operation.Orifices,control valves,transmitters,thermocouples,level gages,and local controllers as well asanalyzer sample points generally should be readily accessible from grade,permanentplatforms,or fixed ladders.In this manual,special consideration is given to the location.accessibility,and readability of the elements.Users of this manual are reminded that in the rapidly advancing field of instrumentationno publication of this type can be complete nor can any written document be substitutedfor qualified engineering analysisCertain systems are not covered in this section because of their highly specializednature and limited use.When any of these systems gains wide-spread usage and installa-tion reaches a fair degree of standardization,this section will be revised to incorporatesuch additional information.Acknowledgment is made to all the engineers and operating and maintenance person-nel who,through years of study,observation,invention,and sometimes trial and error.have contributed to the technology of instrumentation.Suggested revisions are invited and should be submitted to the director of the RefiningDepartment,American Petroleum Institute,2101 L Street,N.W,Washington.D C20037.公PREFACEThis section is one of a series which make up RP 550,Manual on Installation ofRefinery Instruments and Control Systems.RP 550 is composed of four parts:Part 1-Process Instrumentation and ControlPart II-Process Stream AnalyzersPart II-Fired Heaters and Inert Gas GeneratorsPart IV-Steam GeneratorsPart I analyzes the installation of the more commonly used measuring and controlinstruments,as well as protective devices and related accessories;Part II presents adetailed discussion of process stream analyzers;Part III covers installation requirementsfor instruments for fired heaters and inert gas generators;and Part IV covers installationrequirements for instruments for steam generators.These discussions are supported bydetailed information and illustrations to facilitate application of the recommendations.The format of RP 550,Part I has been changed to facilitate continuity of presentation,convenience of reference,and flexibility of revision.Each section is now being publishedindividually as follows:Section 1-FlowSection 2-LevelSection 3-TemperatureSection 4-PressureSection 5-Automatic ControllersSection 6-Control Valves and PositionersSection 7-Transmission SystemsSection 8-Seals.Purges,and WinterizingSection 9-Air Supply SystemsSection 10-Hydraulic SystemsSection I1-Electrical Power SupplySection 12-Control CentersSection 13-Alarms and Protective DevicesSection 14-Process Computer SystemsWhen preparing these documents.it was necessary to decide on a logical method ofpresentation-should each point be explained as fully as possible,or should extensivecross-referencing be done between sections?The publications contain a combination of these methods of presentation Each sectionhas been made as complete as possible,with cross-referencing done only where veryextensive repetition would have been required.Users of this recommended practice are cautioned to obtain a complete set of sections toaccomplish efficiently any cross-referencing that is required for a better understanding ofthe subject matter.4