WIXLIB

Ta b l e 4D e s i g n S t r e s s I n t e n s i t y Va l u e s i n T e n s i o n f o rA n n e a l e d T i ta n i u m a n d T i ta n i u m A l l o Y s , K S I *Spec.No.ASTMGradeTIMETALP-No.Plate, Sheet and StripSB-265135A250A365A750A .15PdPipe and TubingSB-337135ASB-338250ASeamless365A750A .15PdSB-337SB-338Welded1237Bar and BilletSB-3481237ForgingsSB-381F1F2F3F7Specified Min. YieldTensile0.2%Strength OffsetNotes100(38)150(66)200(93)For Metal Temperature Not Exceeding F ( 98.04.77.58.97.54.27.38.07.335A50A65A50A 7.66.43.66.26.86.235A50A65A50A .27.38.07.335A50A65A50A .27.38.07.3NOTES: (1) A quality factor of 0.85 has been applied in arriving at the design intensity values of this material.(2) Filler metal shall not be used in the manufacture of welded tubing or pipe.*From Table ANF-1.4 ASME Boiler and Pressure Vessel Code, Section VIII-Division 2 (prior to 1995).From Table 2B, Section II, Part D, ASTM Boiler and Pressure Vessel Code, for Section VIII, Division 2 Service (since 1995).FIGURE 1C h a rt f or de t e r m i n i n g s h e l l t h ic k n e s s of c y l i n dr ic a l a n d s p H e r ic a l v e s s e l s u n de re x t e r n a l p r e s s u r e w h e n c o n s t r u c t e d o f t i m e t a l 5 0 a ( g r a d e 2 ) u n a l l o y e d t i ta n i u m25,000G E N E R A L N O T E : S E E TA B L E N T F - 2 F O R TA B U L A R VA L U E SUP TO 100 F (38 C)20,000200 F (93 C)18,00016,00014,000400 F (204 C)12,0009,0008,0007,0006,0005,000EEEE 00.00001234567 8 9.0001234567 8 9.001FA C T O R A234567 8 92.01Pa 4B———3(D /t) 3and456Pa 7 8 9.12AE———3(D /t) Instructions for calculating A and B and for using this chart are given in ASME Boiler and Pressure Vessel Code Section VIII Division 1 Part UG paragraph UG-28.From Fig. 5-UNF-28.28 Appendix 5 Section VIII, Division 1 ASME Boiler and Pressure Vessel Code (prior to 1995).From Fig. NFT-2, Section II, Part D ASME Boiler and Pressure Vessel Code (since 1995).4FA C T O R B10,000600 F (316 C)

are obtained using the prescribed ASMEBoiler Code Procedure, i.e., the lesser ofone fourth of the ultimate tensilestrength or one third of the 2% offsetyield strength at each given temperature.Various product forms of annealedTIMETAL (ASTM Grade) alloys arecovered in this table. Design stressintensity values (for less severe service)for Section VIII-Division 2 constructionare given in Table 4. Figures 1 and 2 arecharts for determining shell thicknessof cylindrical and spherical vessels underexternal pressure when constructedof TIMETAL 50A (Gr. 2) and TIMETAL65A (Gr. 3), respectively, followingASME procedures.to be used down to -75 F (-59 C)provided the user is satisfied thatsuitable ductility is available at thedesign temperature. Notched andunnotched tensile tests are suggested byASME as means whereby the titaniumalloy can be judged to be suitable.L o w Te m p e r a t u r e sTitanium has excellent properties at lowtemperatures. Best ductility at very lowtemperatures is available from TIMETAL35A (Gr. 1) and TIMETAL 50A (Gr. 2).However, no marked drop in impactresistance is observed at subzerotemperatures in any of the titaniumalloys. Because of this, the ASME Boilerand Pressure Vessel Code allowsunalloyed titanium TIMETAL 35A (Gr. 1),TIMETAL 50A (Gr. 2), TIMETAL 65A(Gr. 3) and TIMETAL 50A .15Pd (Gr. 7)FIGURE 2C h a rt f or de t e r m i n i n g s h e l l t h ic k n e s s of c y l i n dr ic a l a n d s p H e r ic a l v e s s e l s u n de re x t e r n a l p r e s s u r e w h e n c o n s t r u c t e d o f t i m e t a l 6 5 a ( g r a d e 3 ) u n a l l o y e d t i ta n i u m30,000G E N E R A L N O T E : S E E TA B L E N T F - 1 F O R TA B U L A R VA L U E SUP TO 100 F (38 C)25,000200 F (93 C)20,00018,00016,00014,000400 F (204 C)10,000600 F (316 C)9,0008,000FA C T O R B12,0007,0006,000EEEE 00.00001234567 8 9.0001234567 8 9.001FA C T O R A234567 8 92.01Pa 4B———3(D /t) 34and56Pa 7 8 9.12AE———3(D /t) Instructions for calculating A and B and for using this chart are given in ASME Boiler and Pressure Vessel Code Section VIII Division 1 Part UG paragraph UG-28.From Fig. 5-UNF-28.22 Appendix 5 Section VIII, Division 1 ASME Boiler and Pressure Vessel Code (prior to 1995).From Fig. NFT-1, Section II, Part D ASME Boiler and Pressure Vessel Code (since 1995).5

Ta b l e 5Welded Tubing Safe External Working Pressure ( psi ) at 100 F (38 C)For Annealed TIMETAL 50A (ASTM Grade 2), TIMETAL 50A .15P d (ASTM Grade 7)and TIMETAL 50A .05P d (ASTM Grade 6613371557175320641"1.00Outside Diameter of 81133192273425551714857According to Part VG Paragraph VG-2B: (1) Calculate Do/t. (2) Obtain Factor A from Figure 5-VGO-28.0 Appendix 5, Section VIII, Division 1 ASME Boiler and Pressure Vessel Code (prior to1995), or from Figure G, Section II, Part D, ASME Boiler and Pressure Vessel Code (since 1995). (3) Obtain Factor B. Refer to Figure 1 (ASTM Grades 2, 7, 16*) or Figure 2 (ASTM Grade 3).4B4B(4) External Pressure Formula: Pa –––––––– assumes a seamless tube. For welded tube: Pa ––––––––– x .85[E .85]3 (Do/t)3 (Do/t)Note: Values in this table may not be exact as they were manually extracted*ASTM Grade 16 is in the process of ASME SB338 approval.from Figure 1 to determine factors A and B in the pressure formula.The safe internal working pressures are shown in Table 5A.Ta b l e 5 aWelded Tubing Safe Internal Working Pressure ( psi ) † At 100 F (38 C)For Annealed TIMETAL 50A (ASTM Grade 2), TIMETAL 50A .15P d (ASTM Grade 7)and TIMETAL 50A .05Pd (ASTM Grade 788951111613311501167319471"1.00Outside Diameter of 53013624235025646267258339601061where S Maximum allowable stress from the seamless tubing section of Table 3, psi; E 0.85 for welded tubing and 1 for seamless tubing;SEtcalculated from P ––––––––t Minimum tube wall thickness allowed (nominal – 10%), inches; and Ro 1/2 the tube outside diameter, inches.Ro – 0.4tIf maximum allowable stress (S) is chosen from the welded tubing section of Table 3, the 85%joint efficiency has already been applied to these values and the following formula 38177919721-3/4"1.75StP ––––––––Ro – 0.4t*ASTM Grade 16 is in the process of ASME SB338 approval.The safe external working pressures are shown in Table 7861951

W e l d e d Tu b i n g – S a f eWorking PressuresSafe external working pressures forannealed TIMETAL 50A (Gr. 2) weldedtubing of various diameters and wallthickness for temperatures up to 100 F(38 C) are given in Table 5. Themultiplying factors given in Table 6allow calculation of safe internalpressures for welded tubing for otheralloys and to temperatures as high as600 F (316 C). The data in Tables 5Aand 6 can be used to select theminimum wall thickness of weldedtubing required for internal pressureand temperature conditions anticipatedin heat exchanger service. Unlike manyother materials, a corrosion allowance isusually not required for titanium.This permits thinner-walled tubing tobe used than is generally practical withother materials.Tu b e V i b r a t i o n a n dRigidityTube vibration in a heat exchangeroccurs when shellside cross flow velocityis too high and baffle spacing is toodistant. Excessive tube vibration mayresult in fatigue failures at supportplates or in midspan collision damage.Titanium’s hardness and corrosionfatigue resistance act to minimizevibration damage, but its lower modulus(than steel or copper-nickel alloys)must be considered in design to keepdeflection within acceptable limits.Proper baffle design and spacing shouldbe incorporated into the designs of bothnew and retrofit titanium tube bundlesto avoid flow induced vibration. Acomparison of static deflections fortitanium tubing and other materials andthe reduction in baffle spacing requiredwhen using titanium tubes is shown inTable 7. The data illustrate that areduction in baffle space is more effectivethan an increase in wall thickness indecreasing deflection. Generally, ifvibration has not been a problem in a heatexchanger, retubing with titanium usingproper baffle spacing will eliminate flowinduced vibration as a potential problem.Ta b l e 6Multiplying Factors to Determine Safe Internal Working Pressuresof Annealed, Welded Titanium Tubing at Elevated Temperatures*TIMETAL35A50A50A .15Pd65ACode 12100 (38)127312For Metal Temperatures Not Exceeding, F ( C)250 (121) 300 (149) 350 (177) 400 (204) 450 (232)150 (66)200 36.672.8321.065.616.7441.000ASTM Grade500 (260)550 (288)600 536.456.480*Select safe working pressure (SWP) for TIMETAL 50A tubing of desired size and gauge from Table 5A. Then use multiplying factor from Table 6 above to determine SWP for desired alloy and temperature.Example: Determine SWP for TIMETAL Code 12 1"x .065" welded tubing at 350 F. From Table 5A, SWP for 1"x .065" TIMETAL 50A welded tubing at 100 F is 1304 psi. The multiplying factorfor TIMETAL Code 12 at 350 F from Table 6 above is 1.065. The SWP for TIMETAL Code 12 at 350 F is calculated as 1.065 x 1304 1389 psi.Ta b l e 7S u p p o rt P l at e S pa c i n g R e d u c t i o nMaterialO.D.Tube Size(Inches)Titanium3/4”70-30 Cu-Ni3/4”90-10 Cu-Ni3/4”Aluminum Bronzeand Admiralty BrassTitanium3/4”170-30 Cu-Ni190-10 Cu-Ni1Aluminum Bronzeand Admiralty Brass1% Spacing ReductionReplacement with Titanium0.035"0.049"20 BWG18 .0651613.97.47

H e a t Tr a n s f e rThe thermal conductivity of titanium isroughly 50% higher than 304 stainlesssteel as shown in Table 8. Thiscontributes to its excellent heattransfer properties.The overall heat transfer coefficient, U(Btu/hr.-ft 2- F), indicates the ability of asurface to transfer heat from onepermit high tube side velocities(minimizing rt), and be usable in thinnestsection (minimizing rm).flowing fluid on one side to another fluidon the opposite side. The inverse of thecoefficient, (1/U), can be considered tobe the total resistance to heat flowwhich, as indicated in Figure 3, is madeup of five component resistances: tubeside fluid, rt, tube-side fouling, rtf, tubemetal, rm, shell-side fouling, rsf, andshell-side fluid, rs. An ideal tube materialwill resist fouling (minimizing rtf and rsf),A zero corrosion allowance can oftenbe specified for titanium. This, coupledwith adequate strength, permitstitanium tubing to be used withunusually thin walls.Ta b l e 8T h e r m a l c o n d u c t i v i t y o f m e ta l s , B t u / h r . - f t.MaterialNaval BrassAdmiralty Brass90-10 Cu-Ni70-30 Cu-NiMonelTIMETAL 50ATIMETAL Code 12Type 304 SS100 F (38 C)7683482041501481042- F/in.200 F (93 C)300 F (149 C)400 F (204 C)500 F (260 C)600 F (316 961068504300204134130136,,,yy,,yy ,,, z ,,yy, y{,,yy,,yy,,yy ,,, z ,,yy, y{,,yy,,yy { FIGURE 3t o ta l r e s i s ta n c e o f h e at e x c h a n g e r t u b e sH E A T T R A N S F E R U x ( M E A N T E M P. D I F F. ) x ( E F F. T U B E A R E A )T E M P E R AT U R EGRADIENTTUBE5X,,,yyy,,yy,,,yyy,,yy,,,yyyT O TA LR E S I S TA N C ETUBE-SIDEFLUIDTUBE-SIDESCALETUBEM E TA L,,yySHELL-SIDESCALE1—– r t r t f r m r s f r sU8SHELLSHELL-SIDEFLUID

distillation and condensation fortitanium, as compared to other metals.The high resistance of titanium tocorrosion prevents buildup of corrosionproducts which rob other metals of heattransfer efficiency. Titanium’s hard,smooth surface also minimizes buildupof external fouling films and makescleaning and maintenance easier.Figure 4 shows the high rates ofThe excellent resistance of titanium toturbulence and erosion-corrosionpermits use of relatively high flow ratesof 18-22 ft./sec. in silt-laden seawateror even up to 100 ft./sec. in cleanseawater without damage to the passiveoxide film. Tests in 80 F (27 C) seawater for 60 days at 25 ft./sec. haveshown titanium’s corrosion-erosionresistance to be 80 times better thanthat of the next-best material, acopper-nickel alloy. Other tests in85 F (29 C) sea water for 60 days at27 ft./sec. proved titanium to be almost100 times better than stainless steel,the next-best material.FIGURE 4C o m p a r at i v e r at e s o f d i s t i l l at i o n a n d c o n d e n s at i o n1210T I TA N I U MTYPE 3161.6T I TA N I U M1.4HASTELLOY C1.2TYPE 3161.0TYPE 3040.80.60.4T I TA N I U M C O N D E N S E S :2 0 . 9 % M O R E T H A N T Y P E 3 0 4 S TA I N L E S S S T E E L1 6 % M O R E T H A N T Y P E 3 1 6 S TA I N L E S S S T E E L4.3% MORE THAN TYPE HASTELLOY CHASTELLOY C0.2TYPE 3040COPPER050100150200250MINUTESGLASS6R E L AT I V E R AT E S O F N I T R I C A C I D D I S T I L L AT I O NFROM A 70% NITRIC ACID SOLUTION1.81.6L I T E R S O F W AT E R D I S T I L L E DL I T E R S O F W AT E R D I S T I L L E D8LITERS OF NITRIC ACID DISTILLED1.8T I TA N I U M C O N D E N S E S :43.8% MORE THAN GLASS31.4% MORE THAN COPPER2 2 . 7 % M O R E T H A N T Y P E 3 0 4 S TA I N L E S S S T E E L15.0% MORE THAN HASTELLOY C1 0 . 8 % M O R E T H A N T Y P E 3 1 6 S TA I N L E S S S T E E L42TYPE 316T I TA N I U M1.4COPPERTYPE 3041.21.00.80.60.4T I TA N I U M C O N D E N S E S :3 3 % M O R E T H A N T Y P E 3 0 4 S TA I N L E S S S T E E L29.3% MORE THAN COPPER2 0 % M O R E T H A N T Y P E 3 1 6 S TA I N L E S S S T E E L0.200024681012141618HOURSR E L AT I V E R AT E S O F W AT E R D I S T I L L AT I O NU S I N G D E I O N I Z E D W AT E R200123456HOURSR E L AT I V E R AT E S O F W AT E R D I S T I L L AT I O NFROM A 3.5% SODIUM CHLORIDE SOLUTIONRates of distillation and condensation are high for titanium compared to other metal heat exchanger surfaces.9

inside 3/4” x 18 gauge tubes and steamwas condensing on the outside. Hadthin-walled titanium tubing been usedas is present practice, the heat transf

aspects of the design, fabrication and maintenance of titanium equipment. Design of titanium equipment has followed traditional standards established for other materials of construction. ASTM mill product specifications, TEMA and ASME Code standards are followed in fabrication. Standard