LiquidRingCompressorsandVacuum PumpsinPetroleum Chemical andGas IndustryServices APISTANDARD681 SECONDEDITION JULY2021 API American Petroleum Institute
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Contents Page 1 Scope. .1 2 Normative References. 1 3 TermsDefinitionsAcronyms andAbbreviations. 4 3.1 Terms and Deinitions.. 4 3.2 Acronyms and Abbreviations 11 4 General.. 11 4.1 Unit Responsibility 11 4.2 Nomenclature... 11 5 Requirements 11 5.1 Units of Measure... 11 5.2 StatutoryRequirements. 11 Conficting Requirements 11 6 Basic Design. 12 6.1 General. 12 6.2 Pressure Casings 15 6.3 Casing Connections.. 17 6.4 Flanges. 19 6.5 ExternalForces andMoments. 20 6.6 Rotating Elements. 22 6.7 Mechanical Shaft Seals 23 6.8 Dynamics 25 6.9 Bearings Bearing Housings and Lubrication.. 27 6.10 Materials. 31 6.11 Sealless Design. 96 6.12 Nameplates and Rotation Arrows. .37 7 Accessories 85 7.1 Drivers. 7.2 Couplings. 40 7.3 Guards. 41 7.4 Belt Drives 42 7.5 Baseplates. 43 7.6 Controls and Instrumentation. 46 7.7 Ring Liquid System and Auxiliaries. 55 7.8 Piping. 58 8 Inspection Testing and Preparation for Shipment. 60 8.1 General. 09 8.2 Inspection 61 8.3 Testing 9 8.4 Preparation for Shipment.. 89 Vendor's Data 71 Annex A (informative) Data Sheets. 72
API STD 681-2021 石油、化工和天然气业用液环真空泵和压缩机 第2版(英文版).pdf
