C C C C. MPa MPa MPa MPa 1E-6/ C 1E-6/ C 1E-6/ C 1E-6/ C C C C C

Transcription

1 ASME UHX14 Floating Tubesheets / Schwikopf Rohrböden Page: 1 Floating tubesheet according to ASMEUHX14 Type of heat exchanger (a,b,c) WArt b a,b,c Heat Exchanger With an Externally Sealed Floating Head (A) Configuration of the tubesheet (af,ad) Type d af,ad Stationary Tubesheet Gasketed With Shell and Channel Shell side internal operation pressure Ps 1.34 Tube side internal operation pressure Pt.268 Shell side internal test pressure Psp Ptp Tube side internal test pressure Load case (1=operation, 2=test at 2 C, 3=other) 1 *) load case: operation Calculation case acc. UHX14.4(a): (1), (2)... (7) 1 (17) Tube side pressure only (Ps=) without thermal expansion Tubesheet material Shell material (Type abc) Tube material Channel material(type aefa) Link another module for the second tubesheet (Y/N)? No (Y/N) Link modules for calculation cases 17 (Y/N)? No (Y/N) Operation Tubesheet Shell Tubes Channel Temperature C C C C Thickness Outs.diam Poiss.rat Allow. c1 Corr.all.c2 Figure Strength for the selected load case temperature Op.strength Test stren. Oper.safety Test safety Emodule**) Therm.dil. 1E6/ C 1E6/ C 1E6/ C 1E6/ C Yield str Limit temp. C C C C All.stress*) Pr.+sec.st*) *)can be overwritten for load case 3 **)Missing Emodule < 1 or coef. of therm. exp.= must be adjusted! Additional specifications for the geometry and loading Tubesheet Tubetubesheet joint (1=expanded, 2=welded) 1 (1, 2) Tube hole diameter, only for welded tubes dah Tube pattern (1=Triangle, 2=Square) 1 (1, 2) Number of tubes Nt 1189 Mean distance between the tubesheet center and the outermost tube hole center Tube pitch (center distance) Expanded length of tube in tubesheet Total untubed area UL1*LL1+UL2*LL2.. Fig.UHX11.2 Depth of tube side pass partition groove Expanded length ratio ltx/h Tube length between inner tubesheet faces Unsupported tube span for buckling Type of tube support (.6=tubesheettubesheet,.8=tubesheet support plate, 1=plateplate ) rt p ltx AL hg ρ L l k

2 ASME UHX14 Floating Tubesheets / Schwikopf Rohrböden Page: 2 Equivalent free buckling length k*l lt 46.4 UHX14.6: Specification only for radial thermal exp. of types abcefa Tubesheet metal temperature at the rim T' 2 C Channel metal temperature at the tubesheet T'c 2 C Shell metal temperature at the tubesheet T's 2 C Mean coefficient of thermal expansion of Tubesheet at T' α' 1E6/ C Channel at T'c α'c 1E6/ C Shell at T's α's 1E6/ C Flange Mean contact diameter tubesheetflange (Type cfc) G1 Bolt circle diameter (Type bcdefbc) C 1257 Bolt number n Bolt root diameter db

3 ASME UHX14 Floating Tubesheets / Schwikopf Rohrböden Page: 3 Total bolt area Bolt material Strength operation Strength test Safety operation Safety test Ab Ks Ksp Ss Ssp Shell Channel Gasket Type d,e,f Type b,c,d Contact outside diameter Ga Contact inside diameter Gi Theoretical seating width b Gasket factor (Table 25.1) m Gasket seating pressure Y Diameter of gasket force G Poisson's ratio ν.3.3 Results acc. UHX9 Schale Vorkaer Effective seating width b Gasket boltup force W N N Gasket operating force W N N Total required bolt area Am Flange thickness hr Bolt root area : Results acc. to UHX14 Gasket seating force =.5(Am+Ab)*Ksp/Ssp, App.25 W N Channel thickness without allowances tc Shell thickness without allowances ts Channel inside diameter corroded (type aefa) Dc Shell inside diameter corroded (type abc) Ds Step 1 acc. UHX 14.5 Basic ligament efficiency for shear µ.2 Effective ligament efficiency for shear µ*.2751 Effective depth of pass partition groove hg' Equivalent radius of outer tube limit circle a Radial channel dimension ac 63.1 Radial shell dimension as Ratio = ac/a ρc 1.74 Ratio = as/a ρs 1.76 Parameter = 1Nt*(.5*daROHR/a)² xs.4432 Parameter = 1Nt*(.5*diROHR/a)² xt.547 Step 2 Type abc: Coefficients for shell pressure δ S ^3/N ßS= 1/, ks= N, λs= Type aefa: Coefficient for channel pressure δ c ^3/N ßC=, kc=, λc= 1/ N Step 3 Effective modulus of el. tubesheet (Fig.UHX11.3) E* 2866 Ratio of elasticity tubesheet E*/E.283 Effective Poisson's ratio tubesheet ν*.3374 Effective tube hole diameter d* 23.2 Parameter for table UHX13.1 Xa Effective pitch p* Zd =.2143, Zv =.13, Zm.1634 Step 4 Diameter ratio = A/D K 1.14

4 ASME UHX14 Floating Tubesheets / Schwikopf Rohrböden Page: 4 F =.2331, Φ =.3118, Q UHX Step 5: Coefficients ωs =, ωs* ωc =, ωc* =.965, γb.24 Results acc. to UHX14.6 and step 6 Tr = 2 C, Ts* = 2 C, Tc* 2 C Ps*=, Pc* =, Pe.268 UHX Step 7 Q2 = N, Q3 =, Fm Strength condition for the tubesheet bending stress, case 1 : Sig = < 1.5 * SigB = case 13 < SPS= case 47 Step 8 Strength condition for the tubesheet shear stress: Tau = <.8* SigB = Step 9 Fq =, Fs = Strength condition for the tube stress with cacluation case 1 : STo = SigT = for calculation case 13 STo 2*SigT= for calculation case 47 STo Stb = (for STo<, Buckling) rt = 8.552, Ft = 47.52, Ct Step 1: Stress σs in the shell and σc in the channel σs = σs = σc = σc = Minimum shell length with uniform thickness Minimum channel thickness with uniform thickness lsm lcm Condition UHX not required for configurations dbcd Geometric conditions: valid Strength condition for linked modules (Connection activated: No ): Allowable primary + secondary shell stress acc. UG23(e): SPSB = 3*Sigzul(a) or 2*Yield strength(b) at operation = 3* or 2* (b) under the condition: SigZul not in the creep range: T= C < C and: Yield strength <.7*tensile strength at room temperature (2 C) UHX11.4(b): The calculation of fixed tubesheets shall be performed with corrosion (corrosion allowance c2>) and without corrosion (c2=). 14.4(b) If: Tubesheet thickness= < 25.4 =tubesheet outside diameter, tubesheet deflection should be considered

5 ASME UHX14 Floating Tubesheets / Schwikopf Rohrböden Page: 5 Formulas acc. UHX14.5 tt = = tvt c1t c2t = h = = tvb c1b c2b = UG step 1 D = 1174 = 2*r + dat) = 2* µ =.2 = (p dat) / p = ( )/ hg' = = MAX[( hg c2t ),] = MAX[( ),) UG Step 2 Ks = Pi*ts*(Ds+ts)*Es/L) =, Kt = Pi*tT*(dttT)*Et/L) = UG step 3 ρ =.958 = ltx / h = / p* = = p / (1 4*AL/π/D²) ^.5 = = / (1 4* /pi/ 1174 ²) ^.5 d* = MAX(d1*, d2*), d1*= ( dt 2* tt ) = ( * ) d2*= ( dt 2* tt * ET / EB * SigT / SigB *ρ) =( * * 1243 / 1243 * / *.958 ) µ* =.2751 = (p* d*) / d* = ( ) / 23.2 Xa12 = ( 24*(1 ny*²) *Nt*E*tT*a²/E*/L/h³ )^.25 = =[ 24*( ²) * 1189 * * * ² /( 2866 * 3588 * ³) ]^.25

6 ASME UHX14 Floating Tubesheets / Schwikopf Rohrböden Page: 6 Floating tubesheet according to ASMEUHX14 Type of heat exchanger (a,b,c) WArt b a,b,c Heat Exchanger With an Externally Sealed Floating Head (A) Configuration of the tubesheet (af,ad) Type A af,ad Floating Tubesheet Integral Shell side internal operation pressure Ps 1.34 Tube side internal operation pressure Pt.268 Shell side internal test pressure Psp Ptp Tube side internal test pressure Load case (1=operation, 2=test at 2 C, 3=other) 1 *) load case: operation Calculation case acc. UHX14.4(a): (1), (2)... (7) 7 (17) Tube and shell side pressure acting with thermal expansion Tubesheet material Shell material (Type abc) Tube material Channel material(type aefa) Link another module for the second tubesheet (Y/N)? No (Y/N) Link modules for calculation cases 17 (Y/N)? No (Y/N) Operation Tubesheet Shell Tubes Channel Temperature C C C C Thickness Outs.diam Poiss.rat Allow. c1 Corr.all.c2 Figure Strength for the selected load case temperature Op.strength Test stren. Oper.safety Test safety Emodule**) Therm.dil. 1E6/ C 1E6/ C 1E6/ C 1E6/ C Yield str Limit temp. C C C C All.stress*) Pr.+sec.st*) *)can be overwritten for load case 3 **)Missing Emodule < 1 or coef. of therm. exp.= must be adjusted! Additional specifications for the geometry and loading Tubesheet Tubetubesheet joint (1=expanded, 2=welded) 1 (1, 2) Tube hole diameter, only for welded tubes dah Tube pattern (1=Triangle, 2=Square) 1 (1, 2) Number of tubes Nt 1189 Mean distance between the tubesheet center and the outermost tube hole center Tube pitch (center distance) Expanded length of tube in tubesheet Total untubed area UL1*LL1+UL2*LL2.. Fig.UHX11.2 Depth of tube side pass partition groove Expanded length ratio ltx/h Tube length between inner tubesheet faces Unsupported tube span for buckling Type of tube support (.6=tubesheettubesheet,.8=tubesheet support plate, 1=plateplate ) rt p ltx AL hg ρ L l k

7 ASME UHX14 Floating Tubesheets / Schwikopf Rohrböden Page: 7 Equivalent free buckling length k*l lt 46.4 UHX14.6: Specification only for radial thermal exp. of types abcefa Tubesheet metal temperature at the rim T' C Channel metal temperature at the tubesheet T'c C Shell metal temperature at the tubesheet T's 2 C Mean coefficient of thermal expansion of Tubesheet at T' α' E6/ C Channel at T'c α'c E6/ C Shell at T's α's 1E6/ C Flange Mean contact diameter tubesheetflange (Type cfc) G1 Bolt circle diameter (Type bcdefbc) C Bolt number n Bolt root diameter db

8 ASME UHX14 Floating Tubesheets / Schwikopf Rohrböden Page: 8 Total bolt area Bolt material Strength operation Strength test Safety operation Safety test Ab Ks Ksp Ss Ssp Shell Channel Gasket Type d,e,f Type b,c,d Contact outside diameter Ga Contact inside diameter Gi Theoretical seating width b Gasket factor (Table 25.1) m Gasket seating pressure Y Diameter of gasket force G Poisson's ratio ν.3.32 Results acc. UHX9 Schale Vorkaer Effective seating width b Gasket boltup force W N N Gasket operating force W N N Total required bolt area Am Flange thickness hr Bolt root area : Results acc. to UHX14 Gasket seating force =.5(Am+Ab)*Ksp/Ssp, App.25 W N Channel thickness without allowances tc Shell thickness without allowances ts Channel inside diameter corroded (type aefa) Dc 1194 Shell inside diameter corroded (type abc) Ds Step 1 acc. UHX 14.5 Basic ligament efficiency for shear µ.2 Effective ligament efficiency for shear µ*.2751 Effective depth of pass partition groove hg' Equivalent radius of outer tube limit circle a Radial channel dimension ac Radial shell dimension as Ratio = ac/a ρc 1.17 Ratio = as/a ρs 1.17 Parameter = 1Nt*(.5*daROHR/a)² xs.4432 Parameter = 1Nt*(.5*diROHR/a)² xt.547 Step 2 Type abc: Coefficients for shell pressure δ S ^3/N ßS= 1/, ks= N, λs= Type aefa: Coefficient for channel pressure δ c.3695 ^3/N ßC=.1855, kc= 17576, λc= / N Step 3 Effective modulus of el. tubesheet (Fig.UHX11.3) E* 2866 Ratio of elasticity tubesheet E*/E.283 Effective Poisson's ratio tubesheet ν*.3374 Effective tube hole diameter d* 23.2 Parameter for table UHX13.1 Xa 8.89 Effective pitch p* Zd =.2168, Zv =.139, Zm.1641 Step 4 Diameter ratio = A/D K 1.31

9 ASME UHX14 Floating Tubesheets / Schwikopf Rohrböden Page: 9 F = 1.343, Φ = 1.796, Q1.496 UHX Step 5: Coefficients ωs =, ωs*.7868 ωc = 3.129, ωc* = 3.51, γb Results acc. to UHX14.6 and step 6 Tr = 13.1 C, Ts* = 2 C, Tc* 17.9 C Ps*=, Pc* =.5699, Pe.2425 UHX Step 7 Q2 = N, Q3 =, Fm Strength condition for the tubesheet bending stress, case 7 : Sig = < 1.5 * SigB = case 13 < SPS= case 47 Step 8 Strength condition for the tubesheet shear stress: Tau = <.8* SigB = Step 9 Fq =, Fs = Strength condition for the tube stress with cacluation case 7 : STo = SigT = for calculation case 13 STo 2*SigT= for calculation case 47 STo Stb = (for STo<, Buckling) rt = 8.552, Ft = 47.52, Ct Step 1: Stress σs in the shell and σc in the channel σs = σs = σc = σc = Minimum shell length with uniform thickness Minimum channel thickness with uniform thickness lsm lcm Geometric conditions: valid Strength condition for linked modules (Connection activated: No ): Allowable primary + secondary shell stress acc. UG23(e): SPSB = 3*Sigzul(a) or 2*Yield strength(b) at operation = 3* or 2* (b) under the condition: SigZul not in the creep range: T= C < C and: Yield strength <.7*tensile strength at room temperature (2 C) UHX11.4(b): The calculation of fixed tubesheets shall be performed with corrosion (corrosion allowance c2>) and without corrosion (c2=). 14.4(b) If: Tubesheet thickness= < 25.4 =tubesheet outside diameter, tubesheet deflection should be considered

10 ASME UHX14 Floating Tubesheets / Schwikopf Rohrböden Page: 1 Formulas acc. UHX14.5 tt = = tvt c1t c2t = h = = tvb c1b c2b = UG step 1 D = 1174 = 2*r + dat) = 2* µ =.2 = (p dat) / p = ( )/ hg' = = MAX[( hg c2t ),] = MAX[( ),) UG Step 2 Ks = Pi*ts*(Ds+ts)*Es/L) =, Kt = Pi*tT*(dttT)*Et/L) = UG step 3 ρ =.958 = ltx / h = / p* = = p / (1 4*AL/π/D²) ^.5 = = / (1 4* /pi/ 1174 ²) ^.5 d* = MAX(d1*, d2*), d1*= ( dt 2* tt ) = ( * ) d2*= ( dt 2* tt * ET / EB * SigT / SigB *ρ) =( * * 1243 / 1243 * / *.958 ) µ* =.2751 = (p* d*) / d* = ( ) / 23.2 Xa12 = ( 24*(1 ny*²) *Nt*E*tT*a²/E*/L/h³ )^.25 = 8.89 =[ 24*( ²) * 1189 * * * ² /( 2866 * 3642 * ³) ]^.25