ASME SECT. VIII DIV-I DIVCODES, STANDARDS & SPECIFICATIONS
ASME Section VIII Division-1, 2 & 3 DivisionHistorical Development of ASME Section VIII DivDiv- 1, 2 & 3 In the early 20th century, explosion of steam boilers in U.S was frequent. Occurring rate 1/day. 1914: ASME Boiler and pressure vessel code is published. 1925: First publication of Section VIII Unfired Pressure Vessels. 1934: API+ASME jointly published unfired pressure vessel code for petroleum industry. 1952: These two codes are merged in to single code: ASME Unfired Pressure Vessel Code Section VIII 1968: ASME Section VIII Div-2 is published and Divoriginal code became Div-1 Div 1997: ASME Sec VIII division 3 is published.
ASME Section VIII Division-1, 2 & 3 DivisionASME Section VIII codes are most widely used worldwide. Section VIII is divided into three divisions: Division 1: Rules for construction of pressure vessels Division 2: Alternative Rules for construction of pressure vessels. Division 3: Alternative Rules for construction of high pressure vessels. Division 1 is used most often since it contains sufficient requirements for majority of pressure vessels. The main objective of ASME Code rules is to establish the minimum requirements that are necessary for safe construction and operation. ASME Code defines the requirements for material, design, fabrication, inspection and testing which are needed to achieve a safe design.
ASME Section VIII Division-1 DivisionScope: Applicable for pressure between 15 psig and 3000 psig. Code requirements do not apply to non pressure parts, however welds which attach non pressure parts on pressure parts shall meet code rules.
World Wide Pressure Vessel CodesDifferent industrial nations, institutions and organizations have developed standards and codes of the pressure vessel for Design Fabrication Inspection These codes and standards help the Design,Fabrication, Inspection engineer to size the vessel properly for its safe operation. Advantages of design codes: Proven design based on experience. Inbuilt factor of safety. Amendments of codes are being done at regular interval based on feed back data, design improvements and technological up gradation in materials and fabrication processes.
ASME Section VIII Division-1 DivisionScope: Code identifies specific items for which it is not applicable. This includes:Fired process tubular heaters (e.g. furnaces). Pressure containers which are integral part of mechanical devices (e.g. pumps, turbines). Piping system and their components.
ASME BOILER & PRESSURE VESSELS CODESI. POWER BOILERS II. MATERIAL SPECIFICATIONS III. NUCLEAR POWER PLANT COMPONENTS IV. HEATING BOILERS V. NONDESTRUCTIVE EXAMINATION VI. RECOMMANDATED RULES FOR CARE & OPERATION OF HEATING BOILERS VII. RECOMMANDATED RULE FOR CARE OF POWER BOILERS VIII. PRESSURE VESSELS DIVISION-1 ,DIVISION-2 & DIVISION-3 DIVISION- ,DIVISIONDIVISIONIX. WELDING & BRAZING QUALIFICATIONS. X. FIBERGLASS-REINFORCED PLASTIC PRESSURE VESSELS FIBERGLASSXI. RULES FOR INSERVICE INSPECTION OF NUCLEAR POWER PLANT COMPONENTS XII. RULES FOR CONSTRUCTION AND CONTINUED SERVICE OF TRANSPORT TANKS.
ASME Section VIII Division-1 DivisionStructure of Sec VIII Div-1: It is divided Divinto three subsections: Subsection A: It consists part UG, general A: requirements for Method of construction . that apply to all pressure vessel parts, Subsection B: It covers requirements that B: apply to various fabrication methods. Subsection B consists of Part UW for welded construction Part UF for forged construction Part UB for brazed construction - Subsection C: It covers requirements for several C: classes of material.
Structure of ASME Section VIII Div-1 DivASME SEC VIII DIV- 1 Consists of: DIV Introduction -U Subsection A -General Requirements (Part UG) Subsection B -Specific Requirements - Methods (Parts UW, UF, UB) Subsection C -Specific Requirements - Materials (Parts UCS, UNF, UHA, UCI, UCL, UCD, UHT, ULW, ULT, UHX) Mandatory Appendices -Appendix 1 to 40 Non Mandatory Appendices -Appendix A, C, LL, MM (25 nos.)
Subsection A -General RequirementsPart UG : General Requirements for all Methods of Construction and all Materials Materials UGUG-4 to UG-15 UG Design UGUG-16 to UG-35 UG Openings and Reinforcement UGUG-36 to UG-46 UG Braced and stayed surfaces UGUG-47 to UG-50 UG Ligaments UGUG-53 to UG-55 UG Fabrication UGUG-75 to UG-85 UG Inspection and Tests UGUG-90 to UG-103 UG Markings and Reports UG-115 to UG-120 UGUG Pressure Relief Devices UG-125 to UG-137 UGUG-
Subsection B -Requirements pertaining to methods of Fabrication of Pressure VesselsPart UW : Requirements for Pressure vessels fabricated by Welding General UWUW-1 to UW-3 UWMaterials UWUW-5 Design UWUW-8 to UW-21 UWFabrication UWUW-26 to UW-42 UWInspection and Tests UWUW-46 to UW-53 UWMarkings and Reports UW-60 UWPressure Relief Devices UW-65 UW-
Part UF : Requirements for Pressure vessel fabricated by Forging Part UB : Requirements for Pressure vessel fabricated by Brazing
Subsection C -Requirements pertaining to Classes of MaterialsPart UCS Requirements for Pressure Vessels Constructed of Carbon and Low Alloy Steels Part UNF Requirements for Pressure Vessels Constructed of Non Ferrous Materials Part UHA Requirements for Pressure Vessels Constructed of High Alloy Steel Part UCI Requirements for Pressure Vessels Constructed of Cast Iron Part UCL Requirements for Welded Pressure Vessels Constructed of Material non corrosion resistant, Integral Cladding, Weld Metal Overlay, Cladding or with Applied Linings Part UCD Requirements for Pressure Vessels Constructed of Cast Ductile Iron
Subsection C -Requirements pertaining to Classes of Materials(Continued)Part UHT Requirements for Pressure Vessels Constructed of Ferritic Steels with Tensile Properties enhanced by Heat Treatment Part ULW Requirements for Pressure Vessels Constructed of Layered Construction Part ULT Alternative Rules for Pressure Vessels Constructed of Material having higher allowable stresses at lower temperatures Part UHX Rules for Shell and Tube Heat Exchangers
ASME SEC VIII DIV 1COVERS THE DESIGN OF PRESSURE COMPONENTS AS LISTED BELOW ----------------------------------------------------------------------------------------------------1. 2. 3. 4. 5. 6. 7. 8. 9. 10. 11. 12.
UGUG-27 ----- THK OF SHELLS UNDER INTERNAL PRESSURE UGUG-28 ----- THK OF SHELLS UNDER EXTERNAL PRESSURE UG- -----STIFFENING UG-29 -----STIFFENING RINGS OF CYLINDRICAL SHELLS UNDER EXTERNAL PRESSURE UGUG-32 & 33 ---- FORMED HEAD , COVERS ELLIPSOIDAL, TORISHERICAL, HEMISHERICAL, CONICAL & TORICONICAL HEADS. UGUG-34 ---- UNSTAYED FLAT HEADS & COVERS UGUG-36 & 37 ---- OPENING IN PRESSURE VESSELS & REINFORCEMENTS UGUG-41 ---- STRENGTH OF REINFORCEMENTS UG -47 ----- BRACED & STAYED SURFACE UG 53 LIGAMENT UWUW -12 & 15 WELD EFFICIENCY & WELDED CONNECTION DESIGN UCS -56 REQUIRMENT OF PWHT UG -99 & 100 HYDROTEST & PNUMATIC TEST REQUIREMENT
PRESSURE VESSEL ASME SEC VIII DIV 1 ---------------------------------------------------------------------------------------------------UGUG-27 ----- THK OF SHELLS UNDER INTERNAL PRESSURE UGUG-28 ----- THK OF SHELLS UNDER EXTERNAL PRESSURE UG- -----STIFFENING UG-29 -----STIFFENING RINGS OF CYLINDRICAL SHELLS UNDER EXTERNAL PRESSURE UGUG-32 & 33 ---- FORMED HEAD , COVERS ELLIPSOIDAL, TORISHERICAL, HEMISHERICAL, CONICAL & TORICONICAL HEADS. UGUG-34 ---- UNSTAYED FLAT HEADS & COVERS UGUG-36 & 37 ---- OPENING IN PRESSURE VESSELS & REINFORCEMENTS UGUG-41 ---- STRENGTH OF REINFORCEMENTS UG -47 ----- BRACED & STAYED SURFACE UG 53 LIGAMENT
UWUW-12 & 15 WELD EFFICIENCY & WELDED CONNECTION DESIGN UCS -56 REQUIRMENT OF PWHT UG -99 & 100 HYDROTEST & PNUMATIC TEST REQUIREMENT
STRUCTURE OF ASME SEC VIII DIV -1 CODE
ASME Section VIII Division-1 DivisionDivision 1 also consists mandatory and non mandatory appendices: Mandatory Appendices: Appendices:It addresses the subjects that are not covered elsewhere in the code. Requirements of this appendices are mandatory.
Nonmandatory Appendices: Appendices:It provides information and suggested good practices. Requirements of these appendices are not mandatory unless specified in purchase order.
ASME Section VIII Division-2 Division Scope of division 2 is identical to that of division 1, however there is no limitation on higher pressure. Allowable stress values are higher for division 2 that division 1, hence division 2 vessels are thinner Vessels constructed with division 2 are economical over division 1 when saving in material cost is higher than the additional cost required to meet stringent requirements of division 2. Economical for higher pressure applications and for more expensive alloy materials.
ASME Section VIII Division 1 and 21. Pressure limit 2. Design Factor Up to 3000 psig --> 3.5 Membrane Stress 3. Stress Analysis --> Max. Principal Stress 4. Stress Theory Theory --> 5. Joint Efficiency 0.75 to 1.0 6. .Engineer. Certification 7. Hydrostatic Test Pressure Not Required 1.3 * MAWP No limitation on pressure, however Div-3 is applicable above 10000 psig -->> 3 Membrane Stress + Bending Stress, Fatigue Maximum Shear Stress Theory -->> No Joint Efficiency Factor U.D.S. &Design Report Certification Required 1.25 * Design Pressure 15 % Less than Div. 1
8. Material Weight Higher Than Div. 2
ASME Section VIII Division-3 Division Applied to vessels operating at internal or external design pressure is generally above 10000 psig. Design rules:Maximum shear stress Elastic plastic analysis Fracture mechanics evaluation
Material and NDE requirements more stringent than division 1 and 2
PARTS OF THE PRESSURE VESSELS1.