Petroleum Petrochemical andNatural GasIndustries-Air-cooledHeat Exchangers APISTANDARD661 SEVENTHEDITION JULY2013 REAFFIRMED JULY2024 American Petroleum Institute
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Contents Page Scope 2 NormativeReferences. 1 3 Terms and Definitions. 2 4 General 5 5 Proposals 7 6 Documentation. 7 6.1 Approval Information. 7 6.2 Final Records. 9 7 Design. 9 7.1 TubeBundleDesign 7.2 Air-sideDesign 23 7.3 Structural Design. 35 8 Materials. 39 8.1 General. 39 8.2 RequirementsforCarbon SteelinSour or Wet HydrogenSulfideService 40 Headers.. 40 8.4 Louvers. 40 8.5 Other Components 41 9 Fabrication of Tube Bundle 41 9.1 Welding... 41 9.2 Postweld HeatTreatment. 42 9.3 Tube-to-TubesheetJoints. 42 9.4 Gasket Contact Surfaces 43 9.5 Thread Lubrication 44 9.6 AlignmentandTolerances 44 9.7 Assembly 44 10 Inspection Examination andTesting. 44 10.1 Quality Control... 44 10.2 Pressure Test. 47 10.3 Shop Run-in. 47 10.4Equipment Performance Testing.. 47 10.5 Nameplates.. 47 11 PreparationforShipment. 48 11.1 General. 48 11.2Surfaces and Finishes 48 11.3Identification andNotification 48 12 Supplemental Requirements 48 12.1 General. 48 12.2 Design. 49 12.3Examination. 49 12.4Testing 50