Introduction

&APage &PThis spreadsheet is designed as an aid in performing pressure vessel calculations in accordance with the ASME Section VIII, Division 1 Boiler and Pressure Vessel Code. The calculations contained in this program are useful for rerating vessels, performing alterations, or for general design studies. The work sheets in the program deal only with the most commonly used portions of the code. The program is not intended to include all aspects of the code. Refer to the applicable sections of the code for restrictions. The calculations take into consideration only stresses imposed as a result of pressure. Other superimposed loads such as piping or equipment reactions, wind loading, fluid shock, etc. must be considered seperately. Including the introduction, there are eleven work sheets in the program.

1. Introduction 2. Shell thickness 3. t for ellipsoidal head 4. t for torispherical head 5. t for hemispherical head 6. t for bolted flat head 7. Material properties 8. External pressure on shells 9. Stiffening ring10. Reinforcement requirement with no added element11. Reinforcement requirement with element added

Shell thicknessMinumum shell thickness for vessel under internal pressure:Calculation based on ASME Section VIII, Division 1 paragraph UG-27.Where:t = minimum required thickness of shell, inchesP = internal pressure, psiR = inside radius of shell course under consideration, inchesS = maximum allowable stress value, psi. at design temperature.E = joint efficiency. See UW-12 for welded shells. See UG-53 for ligaments between openings.The minumum thickness will be the greater thickness of t = (PR)/(SE - 0.6P) for circumferential stress ort = (PR)/(2SE + 0.4P) for longitudinal stress.Enter Values:P =35psiR =172inchesS =17500psiNOTE: The value of S is selected from the allowable stress tables and for the appropriste design temperature ininE =0.85Section 2D ot the ASME code. Do not use yield or tensilestregnth values as in API 653 calculations.Based on circumferential stress, t =0.405inchesBased on longitudinal stress, t =0.202inchesUSE t =0.405inches

&APage &P

t for Ellipsoidal HeadThickness calculation for ellipsoidal head. Based on ASME Section VIII, paragraph UG-32(d)t=(PD)/(2SE - 0.2P)wheret = minimum required thickness of head, inchesD = inside diameter of head at skirt, inchesP = internal design pressure, psiE = joint efficiencyS = maximum allowable stress value, psiEnter values:P =35psiD =162inchesS =13800psiE =1Calculated thickness, t =0.205inches

&APage &PFormed vessel heads generally fall into one of three categories: ellipsoidal, torispherical, or hemispherical.

Ellipsoidal: Inside depth of the head minus the skirt is equal to one fourth of the inside diameter of the skirt. These are also commonly refered to as 2:1 elliptical heads.

Torispherical: Inside crown radius is equal to the outside diameter of the skirt and the knuckle radius is 0.06 times the inside crown radius.

It will not be readily apparent in the field whether a head is ellipsoidal or torispherical so it's best to consult vendor drawings and data.

The calculations below are for pressure on the concave side.

t for Torispherical HeadThickness calculation for torispherical head. Based on ASME Section VIII, paragraph UG-32(e)t = (.885PL)/(SE-0.1P)wheret = minimum required thickness of head, inchesL = inside spherical or crown radius, inchesP = internal design pressure, psiE = joint efficiencyS = maximum allowable stress value, psiEnter values:P =35psiL =146inchesS =13800psiE =1Calculated thickness, t =0.328inches

&APage &PFormed vessel heads will generally fall into one of three categories: ellipsoidal, torispherical, or hemispherical.

Ellipsoidal: Inside depth of the head minus the skirt is equal to one fourth of the inside diameter of the skirt. These are also commonly refered to as 2:1 elliptical heads.

Torispherical: Inside crown radius is equal to the outside diameter of the skirt and the knuckle radius is 0.06 times the inside crown radius.

It will not be readily apparent in the field whether a head is ellipsoidal or torispherical so it's best to consult vendor drawings and data.

The calculations below are for pressure on the concave side.

t for Hemispherical HeadThickness calculation for hemispherical heads. Based on ASME Section VIII, paragraph UG-32(f)t = (PL)/(2SE-0.2P) wheret = minimum required thickness of head, inchesL = inside spherical or crown radius, inchesP = internal design pressure, psiE = joint efficiencyS = maximum allowable stress value, psiEnter values:P =4500psiL =6.8inchesS =30000psiE =1Calculated thickness, t =0.518inchest is less than 0.365L or P is less than 0.665SE; therefore, code formula is valid.

&APage &PFormed vessel heads will generally fall into one of three categories: ellipsoidal, torispherical, or hemispherical.

Ellipsoidal: Inside depth of the head minus the skirt is equal to one fourth of the inside diameter of the skirt. These are also commonly refered to as 2:1 elliptical heads.

Torispherical: Inside crown radius is equal to the outside diameter of the skirt and the knuckle radius is 0.06 times the inside crown radius.

It will not be readily apparent in the field whether a head is ellipsoidal or torispherical so it's best to consult vendor drawings and data.

The calculations below are for pressure on the concave side.

t for Bolted Flat HeadCALCULATION FOR THICKNESS OF BOLTED, FLAT UNSTAYED CIRCULAR HEADS, COVERS, AND BLIND FLANGESEnter values:Bolt circle diameter48.625inchesNominal bolt size0.75inchesNumber of bolts52Gasket Factor, m =3.75Seating stress, y =9000psiGasket O.D., Go =47.375inchesGasket I. D., Gi =46.375inchesSealing Face O.D., Fo =47.375inchesSealing Face I.D., Fi =44.5inchesDesign pressure, P=115psiAllowable bolt stress at ambient temperature, Sb =20000psiAllowable stress for head at design temp, S =17500psiCalculated values:Bolt area, single boltA =0.334in2Total bolt areaAb =17.368in2Diameter at location of gasket load reactionG =46.88inchesWidth used to determine basic seating width, boN =0.50inchesSCROLL DOWNBasic seating width, table 2-5.2, Appedix 2, ASME Sect. VIIIbo =0.25Effective gasket seating width, table 2-5.2, App. 2 ASME Sect VIIIb =0.25Bolt area req'd for seatingAm2 =Wm2/Sb =16.57in2Initial bolt load for seating gasketWm2 =3.14bGy =331340lbs.Bolt area req'd for operatingAm1 =Wm1/Sb =11.51in2Bolt load required for operating conditionsWm1 =.785G2P + 6.28bGmP =230212lbs.Bolt area selected16.567in2Head thickness based on operating conditionst1 =2.191inchesHead thickness based on gasket seatingt2 =0.8865658828inchesOperating conditions govern therefore use t12.191inches

&APage &PNOTE:

1. This program calculates the minimum required thickness for bolted, flat unstayed circular heads, covers, and blind flanges of the type shown in Fig. UG-34, sketch (j) and sketch (k) of Part UG-34 in the ASME Boiler and Pressure Vessel Code, Section VIII, Division 1.

2. Enter the decimal equivalent of fractions for all dimensions.

3. Gasket Factor, m, and Seating Stress, y, for a given gasket material are obtained from table 2-5.1 in Appendix 2 of the ASME Code or table UA-49.1 in the Lamons Gasket Handbook.

4. The basic gasket seating width, bO, in cell C24 must be selected from table 2-5.2 in Appendix 2 of the ASME Code or table UA-49.2 in the Lamons Gasket Handbook and manually entered at the cell location.

5. All formulas and tables in the Lamons Handbook are taken from Appendix 2 of the ASME Boiler and Pressure Vessel Code, Section Vlll, Division 1.

Material PropertiesMAXIMUM ALLOWABLE STRESS, KSI, FOR METAL TEMP. OF ===>cont'd ==>Nominal CompositionSPEC NO.TYPE/ GRADEPRODUCT FORMMINIMUM TENSILE, psiMINUMUM YIELD, psi-20 to 10015020025030040050060065070075080085090095010001050110011501200125013001350140014501500C-Mn-SiSA36plate, sheet58,00036,00014.514.514.514.514.514.514.514.514.5C-MnSA53S/Bsmls. pipe60,00035,00015.015.015.015.015.015.015.015.015.014.413.010.87.85C-SiSA106Bsmls. pipe60,00035,00015.015.015.015.015.015.015.015.015.014.413.010.88.76.54.52.5CSA179smls. tube47,00026,00011.811.811.811.811.811.811.811.811.811.510.69.27.96.51Cr-1/5 MoSA193B7bolting (