# Blind Flange Design Calculations

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DESIGN CALCULATIONS OF HEAT EXCHANGERAccording to ASME Code, Sec. VIII, Div. 1, Edition 2001, Addenda 2002 / TEMA "R" 7th Edition 88. Designed by : Eng. Abdel Halim Galala, Design General Manager (Assistant)Page : 76 of 136 Sheet : 1 of 6 Rev. : 0Project : Design & Fabrication of Heat Exchanger for APRC Refinery Job No. : 7443-33 Dwg. No. : 7443-33-1A, Rev. 0 Exchanger : Residue Cooler, Type : AES, TEMA class : RSheet : 14Date : 4.7.2003 Location : Alex. Client : APRCItem : E-323A/B & E-514C/DP. Flat Unstayed Circular Blind Flange(Channel Cover) Thickness (item no. 22) [UG-34 & Fig. UG-34 Sketch (j)] [Attached by Bolts] Subjected to internal pressure Blind Cover Material, Clad Metal : SB171 UNS No. C63000 ASME SA266 Class 2 Stud bolt material SA 193 Grade B7 o o F C Design Temperature 140 60 o o Min. Design Metal Temperature, MDMT F C 53.6 12 o o F C Bolt-up and Gasket Seating Temperature 86 30 Assume corrosion allowance, C [UG-25] 0.19685 INCH 5 MM Kg/CM2G Operating Pressure (tube side) 56.8182 PSIG 4 Internal Design Pressure, P (MAWP) 71.7082 PSIG 5.04826 Kg/CM2G Allowable Stress of Bolt Material, SB : * at design temp.(operating condition), Sb * or at atmospheric temp./bolt-up temp. (gasket seating), Sa Allowable Stress of Flange Material : * at design temp.(operating condition), SfH * or at atmospheric temp./bolt-up temp. (gasket seating), SfC [Table 1A , SubPart 1 , ASME Sec. II , Part D] Joint efficiency, E Bolt Hole, Flange outside diameter, A Bolt circut diameter (B.C.D.), 25000 25000 20000 20000 1 1.10236 26.9685 24.5276INCH INCH INCHPSIG PSIG PSIG PSIG1760 1760 1408 1408Kg/CM2G Kg/CM2G Kg/CM2G Kg/CM2G28 685 623MM MM MMFig. UG-34, Sketch (j) Figure (5)No. of bolts Nominal bolt dia., dB Actual cross-sectional area of each bolt, Total actual cross-sectional area of bolts, Ab Flange face outer diameter Flange face inner diameter[TEMA Table D-5]28 1 0.551 15.428 22.1654 19INCH INCH2 INCH INCH INCH225.4 355.4832 9953.528 563 482.6MM MM2 MM2MM MMDESIGN CALCULATIONS OF HEAT EXCHANGERAccording to ASME Code, Sec. VIII, Div. 1, Edition 2001, Addenda 2002 / TEMA "R" 7th Edition 88. Designed by : Eng. Abdel Halim Galala, Design General Manager (Assistant)Page : 77 of 136 Sheet : 2 of 6 Rev. : 0Project : Design & Fabrication of Heat Exchanger for APRC Refinery Job No. : 7443-33 Dwg. No. : 7443-33-1A, Rev. 0 Exchanger : Residue Cooler, Type : AES, TEMA class : RSheet : 14Date : 4.7.2003 Location : Alex. Client : APRCItem : E-323A/B & E-514C/DP. Flat Unstayed Circular Blind Flange (Channel Cover) Thickness (item no. 22) (cont.) [Attached by Bolts] [UG-34 & Fig. UG-34 Sketch (j)] Gasket Details: - Flat metal, jacketed asbestos filled, soft copp[er or brass - Outside diameter - Inside diameter = O.D - 2N - Width, N Gasket Dimensions: Basic gasket seating width, bO = N/2 [Table 2-5.2] Since bo > 1/4 ", Effective gasket seating width, b = 0.5 SQRT(bO) [Table [Table 2-5.1] Gasket Factor, m Min. Seating Stress, y [Table 2-5.1] Facing Sketch [Table 2-5.1] 0.125 22.0472 20.8661 0.59055 0.29528INCH INCH INCH INCH INCH3.175 560 530 15 7.5MM MM MM MM MM0.2717 INCH 3.5 6500 PSIG (1a); Column II6.901087 MM 457.6Kg/CM2GDiameter at location of gasket load reaction, d ( d represnts G ) When bo is larger than 1/4", d = O.D.of gasket contact face - 2 b [Appendix 2-3]21.5039INCH546.1978 MMFactor depending upon method of attachment of head, C [Fig. UG-34, Sketch (j)] 0.3 Gasket moment arm, hG = (B.C.D - d)/2 = (C-G)/2 [Table 2-5.2] 1.51185INCH38.40109 MMCalculating the Min. required Thickness of Blind Flange, t: [UG-34(c)(2)] t = d CP/SE +1.9W hG /SEd3 When using this formula, the thickness t shall be calculated for both operating conditions, and gasket seating, and the greater of the two values shall be used.SA 193 Grade B7 o F 100 140 PSI 25000 ? ASME SA266 Class 2 o F 100 140 PSI 20000 ?150 25000 200 20000DESIGN CALCULATIONS OF HEAT EXCHANGERAccording to ASME Code, Sec. VIII, Div. 1, Edition 2001, Addenda 2002 / TEMA "R" 7th Edition 88. Designed by : Eng. Abdel Halim Galala, Design General Manager (Assistant)Page : 78 of 136 Sheet : 3 of 6 Rev. : 0Project : Design & Fabrication of Heat Exchanger for APRC Refinery Job No. : 7443-33 Dwg. No. : 7443-33-1A, Rev. 0 Exchanger : Residue Cooler, Type : AES, TEMA class : RSheet : 14Date : 4.7.2003 Location : Alex. Client : APRCItem : E-323A/B & E-514C/DP. Flat Unstayed Circular Blind Flange (Channel Cover) Thickness (item no. 22) (cont.)[Attached by Bolts] [UG-34 & Fig. UG-34 Sketch (j)]Calculating the total bolt load, W (for circular heads): 1. For operating conditions, the value of P shall be the design pressure, and the value of S at the design temperature and W from Formula (3) of 2-5(e) shall be used. Flange Design Bolt Load for circular heads, W [Appendix 2-5(e)] For operating conditions, W = Wm1 (3) Wm1 = H + Hp = 0.785 G2P + (2b x 3.14 GmP) (1) [Appendix 2-5(e35243.2 Flange thicknesst = d CP / SE + 1.9Wh G / SEd^ 3lb INCH15986.05 Kg 21.74301 MM0.856022. For gasket seating, P equals zero, and the values of S at atmospheric and W from Formula (4) of 2-5(e) shall be used.[UG-34(c)(2)]P S [Appendix 2-5(e)] Flange Design Bolt Load for circular heads, W For gasket seating, W = 0.5(Am + Ab) Sa (4) Total required cross-sectional area of bolts, Am = Max (Am1,Am2) Required bolt load under atmospheric temp.conditions, Wm2 = 3.14bGy * Total cross-sectional area of bolts at root of thread requiired Am1 = Wm1/ Sb at operating conditions , * Total cross-sectional area of bolts at root of thread required gasket seating, Am2 = Wm2/ Sa Total required cross-sectional area of bolts, Am = Max (Am1,Am2) For gasket seating, W = 0.5(Am + Ab) Sa (4)0 20000PSIG PSIG0 1408Kg/CM2G Kg/CM2G(2) 119246lb54089.04 Kg1.40973INCH2909.4991 MM24.76983 4.76983 252473 1.29857 1.29857 1.29921 2.00787 2.48031INCH2 INCH23077.304 MM2 3077.304 MM2 114519.9 Kg 32.98372 MM 32.98372 MM 33 MM 51 MM 63 MMlbINCH INCH INCH INCH INCHt = d CP / SE + 1 .9Wh G / SEd^ 3t = max. of t of operating and gasket seating Use t without corrosion allowance Use t for construction including R.F. N.B. Check which the deflection is considered a governing thickness or not. The deflection is ehe governing thicknessDESIGN CALCULATIONS OF HEAT EXCHANGERAccording to ASME Code, Sec. VIII, Div. 1, Edition 2001, Addenda 2002 / TEMA "R" 7th Edition 88. Designed by : Eng. Abdel Halim Galala, Design General Manager (Assistant)Page : 79 of 136 Sheet : 4 of 6 Rev. : 0Project : Design & Fabrication of Heat Exchanger for APRC Refinery Job No. : 7443-33 Dwg. No. : 7443-33-1A, Rev. 0 Exchanger : Residue Cooler, Type : AES, TEMA class : RSheet : 14Date : 4.7.2003 Location : Alex. Client : APRCItem : E-323A/B & E-514C/DP. Flat Unstayed Circular Blind Flange (Channel Cover) Thickness (item no. 22) (cont.) [Attached by Bolts] [UG-34 & Fig. UG-34 Sketch (j)]CONCLUSION:FLANGE SUMMARY Flange thickness (without C.A.) Use t for construction including R.F. For a proper design of flange : 1. You have to make a check for flange deflection. 1.29857 2.04724INCH INCH32.98372 MM 52 MMGASKET SUMMARY Gasket width, N Required cross-sectional of bolts, Am Actual cross-sectional area of bolts, Ab BOLT SUMMARY No. of bolts Size of bolt (the bolt size is represented by its actual cross-sectional area) Bolt hole dia. Total required cross-sectional area of bolts, Am Total actual cross-sectional area of bolts, Ab Actual cross-sectional area of bolt, [TEMA TABLE D-5]0.59055 4.76983 15.428INCH INCH2 INCH215 MM 3077.304 MM2 9953.528 MM228 1 1.125 4.76983 15.428 0.551BoltINCH INCH INCH2 INCH2 INCH225.4 28.575 3077.304 9953.528 355.4832MM MMMM2 MM2 MM2Since the actual bolt area Ab > The required bolt area Am, the bolts are adequately enough. N.B. When using bolt with size Total required cross-sectional area of bolts, Am Total ctual cross-sectional area of bolts, Ab Actual cross-sectional area of bolt, [TEMA TABLE D-5] Since the actual bolt area Ab < The required bolt area Am, the bolts are inadequately enough. Edge distance, E from drawing = 1/2 (A - C) Min. Edge distance, E (for bolt size 0.75") Min. Edge distance, E (for bolt size 1") Min. edge distance, E (for bolt size 1-1/8") [TEMA Table D-5] Min. Edge distance, E (for bolt size 1.25") 0.75 4.76983 8.456 0.302 INCH INCH2 INCH2 INCH2 NA1.22047 0.8125 1.0625 1.125 1.25INCH INCH INCH INCH INCH31 20.6375 26.9875 28.575 31.75MM MM MM MM MMDESIGN CALCULATIONS OF HEAT EXCHANGERAccording to ASME Code, Sec. VIII, Div. 1, Edition 2001, Addenda 2002 / TEMA "R" 7th Edition 88. Designed by : Eng. Abdel Halim Galala, Design General Manager (Assistant)Page : 80 of 136 Sheet : 5 of 6 Rev. : 0Project : Design & Fabrication of Heat Exchanger for APRC Refinery Job No. : 7443-33 Dwg. No. : 7443-33-1A, Rev. 0 Exchanger : Residue Cooler, Type : AES, TEMA class : RSheet : 14Date : 4.7.2003 Location : Alex. Client : APRCItem : E-323A/B & E-514C/DP. Flat Unstayed Circular Blind Flange (Channel Cover) Thickness (item no. 22) (cont.) [Attached by Bolts] [UG-34 & Fig. UG-34 Sketch (j)] Actual Bolt spacing, B (c/c) from drawing 2.74622 INCH Min. Bolt spacing, B (for bolt size 0.75") 1.75 INCH Min. Bolt spacing, B (for bolt size 7/8") [TEMA Table D-5] 2.0625 INCH Min. Bolt spacing, B (for bolt size 1") 2.25 INCH Min. Bolt spacing, B (for bolt size 1-1/8") 2.5 INCH Min. Bolt spacing, B (for bolt size 1-1/4") 2.8125 INCH Max. Recommended bolt spacing, Bmax = 2 dB + 6 t / (m + 0.5) [TEMA RCB 3.94882 INCH Check for Flat Channel Cover Deflection [TEMA RCB-9.21] The effective thickness of a flat channel cover shall be the thickness at the bottom of the pass partition groove (or the face if there is no groove) minus corrosion allowance in excess of groove depth. The thickness is to be at least that required by the appropriate Code formula and thicker if required to meet proper deflection criteria. The recommended limit for channel cover deflection is: 0.03" for nominal diameters thru 24" 0.03 INCH 0.125% of nominal diameters (nominal diameter/800) for larger sizes 0.025 INCH 20 INCH Nominal diameter = Shell ID + 2 ts A method for calculating of channel cover deflection at the center, Y is:G Y = 0.0435G 3 P+0.5S B A B h G ET 369.75387 44.45 52.3875 57.15 63.5 71.4375 100.3MM MM MM MM MM MM MM0.762 0.635 508MM MM MM()INCH PSI INCH PSIG PSIG INCH2 INCH 546.1978 MM2214784.07 Kg/CM G2WhereG = Gasket load reaction diameter as defined by the Code 21.5039 E = Modulus of elasticity at design temperature [ASME Sec.II,Part D, TM-31460000 T = Thickness under consideration (minus groove and C.A.) 1.29921 P = Design pressure 71.7082 SB = Allowable bolting stress at design temperature (Wm1) 25000 AB =Actual total cross-sectional root area of bolts 15.428 hG = Radial distance from diameter G to bolt circle 1.5118533 5.04826 25000 9953.528 38.40109MMKg/CM2G Kg/CM2GMM2 MMIf the calculated deflection is greater than the recommended limit, the deflection may be reduced by acceptance methods such as: (a) Increase channel cover thickness by the cube root of the ratio of calculated deflection to the recommended limit. (b) Use of strong backs. (c) Change type of construction. Note: For single pass channels, or others in which there is no pass partition gasket seal against the channel cover, no deflection criteria need be considered.DESIGN CALCULATIONS OF HEAT EXCHANGERAccording to ASME Code, Sec. VIII, Div. 1, Edition 2001, Addenda 2002 / TEMA "R" 7th Edition 88. Designed by : Eng. Abdel Halim Galala, Design General Manager (Assistant)Page : 81 of 136 Sheet : 6 of 6 Rev. : 0Project : Design & Fabrication of Heat Exchanger for APRC Refinery Job No. : 7443-33 Dwg. No. : 7443-33-1A, Rev. 0 Exchanger : Residue Cooler, Type : AES, TEMA class : RDate : 4.7.2003Location : Alex.Sheet : 14Client : APRCItem : E-323A/B & E-514C/DP. Flat Unstayed Circular Blind Flange (Channel Cover) Thickness (item no. 22) (cont.) [Attached by Bolts] [UG-34 & Fig. UG-34 Sketch (j)] The calculated deflection isY = G E T3(0.0435 G3P + 0.5 S B AB hG)0.10054 0.03INCH INCH2.553795 MM 0.762 MMThe recommended deflection limit Since the calculated deflection exceeds the recommended deflection, we have to increase the flange tickness by the cubic root of the ratio of deflections,Tassumed = T +3Ycalculated [TEMA RCB-9.21] Yrecommended2.88948INCH73.39285 MMY =Easier approach : 1. Assume T,G 0.0435 G 3 P + 0.5 S B AB hG E T3()0.00914INCH0.232149 MM1.88283Y = G 0.0435 G 3 P + 0.5 S B AB hG E T3INCH INCH INCH47.824MM2. Find Calculated deflection3. Recommended deflection limit()0.03303 0.03 OK 1.88283 1.889760.839054 MM 0.762 MM4. Compare the calculated deflection with the recommended deflectionThe minimum thickness of channel cover at bottom of pass partition is The thickness neglecting corrosion allowance is Conclusion : Checking of Deflection The min. thickness of channel cover to resist the internal pressure is Where the min. thickness of channel cover to avoid deflection is The min. thickness of channel cover as derived from drawings is The flange thickness increased by Tthickness including groove depth ( 5 MM) Overall thickness including raised faces & groove depth Max. Working Pressure, MWP at New (cold) & Operating (corroded) at New (cold) P = SE t2 /d2 c - 1.9 W hG / d3 c at Operating (corroded) P = SE t2 /d2 c - 1.9 W hG / d3 cINCH INCH47.824 48MM MM1.33858 1.88976 1.9685 0.07874 2.08661 2.48031INCH INCH INCH INCH INCH INCH34 48 50 2 53 63MM MM MM MM MM MM104.094 104.094PSIG PSIG2 7.328196 Kg/CM G 2 7.328196 Kg/CM G

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