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Pipe Branch Reinforcement per ASME B31.1 -2010 Power Piping Code Branch (1) Calculations 3/11/2012, ReinfS1.xls Client: Description: Prepared By Page 1 of 2 Approval Date Ben A. Nottingham Rev. 0 Customer No.: Item No.: 1 2 Owner No.: Dwg. No.: 3 4 The user is responsible to verify method and results. Refer to para. 104.3.1 and Fig. 104.3.1(D) of the Code -20 to Design Temperature 400 deg. F (to 204 deg. C) Dimensional Units Inch Rating is based on design Design Pressure Design pressure: 350 psig = 24.6 kg/cm^2 = 24.1 bar-G = 2413 kPa Material Data per ASME B31.1 -2010, Tables A-1 thru A-9 Materials: Run Pipe: Appendix H, Example 4, Run & Branch: Carbon Steel, API 5L-A Seamless Pipe UNS no.: ---- Line Pipe Branch: Allowable stress, SEh = 16 ksi = 110 MPa Coefficient Y = 0.4 Notes: para. H304 in ASME B31.3 Weld: S-1 Weld joint factor, E h = 1.00 Weld strength red. factor, W h = 1.00 Appendix H, Example 4, Run & Branch: Carbon Steel, API 5L-A Seamless Pipe UNS no.: ---- Line Pipe Reinf: Allowable stress, SEb = 16 ksi = 110 MPa Coefficient Y = 0.4 Notes: para. H304 in ASME B31.3 Weld: S-1 Weld joint efficiency factor, E b = 1.00 Weld strength reduction factor, W b = 1.00 Appendix H, Example 4, Run & Branch: Carbon Steel, API 5L-A Seamless Pipe UNS no.: ---- Line Pipe Allowable stress, SEr = 16 ksi = 110 MPa Weld: S-1 Notes: para. H304 in ASME B31.3 Does Branch-1 intersect a longitudinal weld on the run? Longitudinal Weld Intersection? Yes Allowable stress of run for reinforcement design, SE hr = SE h when branch intersects a weld on the run, or SE hr = SE h / E h when the branch does not intersect a weld on the run. 16.0 ksi Dob = 4.5 in. tnb = 0.237 in. or h2 = 0.000 in. Check if diameter and thickness ratios are reasonable using criteria from ASME B31.3, para. 304.3.1(b)(1) & (2). D ob / D oh = (D ob / D oh ) must not exceed 1.0 OK … Branch OD is not greater than Run OD. 0.52 D oh / T h = 30.6 D oh / 2 = 4.3 in. in. Thickness allowance (corrosion, etc.) Allowances Run Dimensions in. Sch 40 per ASME B36.10M Wall thk: Doh = Pipe nominal thickness tnh = 0.322 in. or h1 = 0.000 in. Millh = 12.5% (D oh /T h ) must not exceed 100, unless D ob <(D oh / 2) Is branch size less than 1/2 of run size? NPS 4 (DN 100) Pipe size: Pipe outside diameter Thk. tolerance: 0.1882 Branch Dimensions NPS 8 (DN 200) Pipe size: Wall thk: SE hr = A= 8.625 in. Sch 40 per ASME B36.10M Pipe outside diameter Pipe nominal thickness: Thk. tolerance: Millb = OK… Run OD/ Run Thk. < 100. See below. OK… Branch OD may be any size not exceeding Run OD. 0.0% Required minimum wall thicknesses. Refer to para. 104.1.2 Eq. (3) and Table 104.1.2(A) of B31.1 Code, t m = [ P D o / (2 (SE + PY )) ] + A t mh = 0.2817 t mhr = 0.2817 in. Run actual measured or minimum thickness, T h = t nh (1 - Mill h ) - h 1 Th = 0.282 in. Run actual corroded thickness (measured or minimum thickness, less corrosion allowance), t ha = T h - A t ha = 0.094 in. t mb = 0.2370 in. Branch actual measured or minimum thickness, T b = t nb (1 - Mill b ) - h 2 Tb = 0.237 in. Branch actual corroded thickness (measured or minimum thickness, less corrosion allowance), t ba = T b - A t ba = 0.049 in. Minimum required run thickness, t mh = [ P D oh / (2 (SE h + PY )) ] + A Minimum required run thickness for reinforcement design, t mhr = [ P D oh / (2 (SE hr + P Y ) ] + A OK… Run thickness IS sufficient at design pressure. Minimum required branch thickness, t mb = [P D ob / (2 (SE b + PY b1 )) ] + A OK… Branch thickness IS sufficient at design pressure 3/11/2012, ReinfS1.xls Pipe Branch Reinforcement per ASME B31.1 -2010 Power Piping Code Branch (1) Calculations Nom. thk. of pad: t nr = 0.322 in. = 8.18 mm Width of pad from edge of branch: w r = 0.875 in. = 22.23 mm Height of saddle above run: h s = n/a -- Weld at pad or ring to branch periphery: W 1s = n/a -- Weld at ring, pad, or saddle outer edge: W 2s = n/a -- Weld at saddle-to-branch periphery: W 3s = n/a -- Page 2 of 2 wwr r wwr r wr ααtn α tri thnr tn rs trrnr Optional Special Weld Dimensions: α Angle between run and branch: = 90 Ring Reinforced (re-pad), 90-degree Branch Comments: -- -- -- -- --- -- -- -- --- -- degrees Integrally Reinforced B31.1 Branch: t r i = n/a -- w r i = n/a -- Leg of 60 deg. triangle = n/a Width integral reinf. area = (tr i) tan 30 Other Dimensions Inside centerline longitudinal dimension of finished branch opening = [ D ob - 2 (T b - A ) ] / sin α d1 = 4.402 in. Half width of reinf. zone = d 1 or (T b - A )+(T h -A ) + d 1 / 2, whichever is greater, but not more than D oh d2 = 4.402 in. Reinf. zone height outside of run pipe, for ring or saddle = 2.5 (T h - A ) or 2.5 (T b - A ) + t nr , whichever is less Lr = 0.234 in. Reinf. zone height outside of run pipe, for integrally reinforced fitting = 2.5 (T h - A ) Li = 0.000 in. Reinf. zone height outside of run pipe = L r + L i L4 = 0.234 in. Outside dimension of reinforcing ring or saddle (along run) = 2 w r + [ (D ob ) ( 2 - sin α ) ] Dr = 6.250 in. t min = 0.000 in. Minimum throat of fillet weld at saddle-to-branch = (smaller of t nb or t nr ) ---[weld reference para. 127.4.8(B)] Min. throat of weld at branch periphery (except saddle or integrally reinf.) = smaller of 6.0 mm (1/4") or 0.7 t nb Minimum leg of weld at branch periphery (except saddle or integrally reinf.) = t c / 0.707 Leg height of weld at branch periphery (except saddle or integrally reinf.) = greater of W 1(min) or W 1s Minimum leg of weld at outer edge of ring, pad, or saddle = 0.5 t nr / 0.707 Leg height of weld at outer edge of ring, pad, or saddle = greater of W 2(min) , or W 2s , but tc = 0.166 in. W 1(min) = 0.235 in. W1 = 0.235 in. W 2(min) = 0.228 in. W2 = 0.228 in. in. not more than smaller of t nr or L 4 (must fit within the reinf. zone) W 3(min) = 0.000 Leg height of fillet weld at saddle-to-branch periphery = greater of W 3(min) or W 3s W3 = 0.000 in. Maximum width of ring, pad, or saddle which would apply = d 2 - (D ob / 2 ) / sin α WR max = 2.152 in. Minimum leg height of fillet weld at saddle-to-branch periphery = 0.7t min /0.707 Rh = 0.234 in. Rw = 0.875 in. Factor for complete fillet welds, other than on ring, pad, or saddle edge, which will fit within the reinf. zone height N wh = 0 Factor for complete fillet welds on ring, pad, or saddle edge which will fit within reinforcement zone width N ww = 2 Reinforcement height (except weld) = lesser of ( t nr or L 4 ) , or lesser of ( t r i or L 4 ), as applicable Reinforcement width (except weld) = (lesser of w r or WR max ), or (lesser of w r i or t ri ) tan 30, as applicable Count of Welds Within Reinforcement Zone Strength Correction Factors Factor for strength correction of branch area = 1 if SE b > SE h , or = (SE b / SE h ) if SE b <= SE h Strength correction factor for reinforcing material = 1 if SE r > SE h , or = (SE r / SE h ) if SE r <= SE h Strength correction factor for welds, F w = lesser of F b or F r Areas Pressure design area expected at end of service life = (t mhr - A ) d 1 Required reinforcement area = A 6 (2 - sin α ) Area of excess thickness in run pipe wall = (2 d 2 - d 1 ) (T h - t mhr ) Area of excess thickness in branch pipe wall = 2 L 4 (T b - t mb ) / sin α Fb = 1.000 Fr = 1.000 Fw = 1.000 A6 = 0.412 in.^2 A7 = 0.412 in.^2 A1 = 0.000 in.^2 A2 = 0.000 in.^2 Total area of welds within zone = (N wh / 2)(W 1 )+(N wh / 2)(W 3 )+(N ww / 2)(W 2 ) A3 = 0.052 in.^2 Area of added reinforcement metal, except welds, within the reinforcement zone = 2 x R h x R w A4 = 0.409 in.^2 Area provided in B31.1 integrally reinforced fitting [See Fig. 104.3.1(D), Example B], = R h x R w A 4i = 0.000 in.^2 Total contributing area (with strength correction for added metal within the reinf. zone) A c = A 1 + (A 2 )(F b ) + (A 3 )(F w ) + (A 4 + A 4i )(F r ) Ac = 0.461 in.^2 2 Percent of area replaced = A c / A 7 % 2 2 This branch has sufficient reinforcement. % Area 112%