RTJ flange dimensions are covered in ASME B16.5 – which covers Pipe Flanges and Flanged Fittings for size NPS ½” to 24” for above NPS 26” to 60” it should be as per ASME B16.47.

During a dimensional inspection of the RTJ flange, you should check for

  • Outer & Inner Diameter of body
  • Bolt Circle & Bolt hole Diameter
  • The thickness of weld end
  • Length of the Hub
  • Straightness and alignment of the bolt hole
  • RTJ Groove Dimensions
rtj flange dimensions

Class 150 Weld neck RTJ Flange Dimensions

Size in InchSize in mmOuter Dia.Flange ThicknessHub ODWeld Neck ODWelding Neck LengthRTJ RF DiaRTJ RF HeightPCDRTJ Pitch diaRTJ DepthRTJ WidthBore
ABCDEFGHIJKL
1/215909.63021.346N/AN/A60.3N/AN/AN/AWelding Neck bore is derived from the pipe schedule
3/42010011.23826.751N/AN/A69.9N/AN/AN/A
12511012.74933.45463.56.3579.447.636.358.74
1 1/43211514.35942.256736.3588.957.156.358.74
1 1/24012515.96548.36082.56.3598.465.076.358.74
25015017.57860.3621026.35120.782.556.358.74
2 1/26518020.79073681216.35139.7101.66.358.74
38019022.310888.9681336.35152.4114.36.358.74
3 1/29021522.3122101.6701546.35177.8131.786.358.74
410023022.3135114.3751716.35190.5149.236.358.74
512525522.3164141.3871946.35215.9171.456.358.74
615028023.9192168.3872196.35241.3193.686.358.74
820034527246219.11002736.35298.5247.656.358.74
1025040528.63052731003306.35362304.86.358.74
1230048530.2365323.81134066.35431.83816.358.74
1435053533.4400355.61254256.35476.3396.886.358.74
1640059535457406.41254836.35539.8454.036.358.74
1845063538.1505457.21385466.35577.9517.536.358.74
2050070041.35595081435976.35635558.86.358.74
2460081546.16636101517116.35749.3673.16.358.74

Class 150 Weld neck RTJ Flange Stud & Bolt Dimensions

RTJ Root RadiusRing noDistance Between FlangesNo of BoltsBolt Size UNCMachine Bolt LengthRTJ Stud LengthHole SizeISO Stud Size
0.8N/AN/A41/250N/A5/8M14
0.8N/AN/A41/250N/A5/8M14
0.815441/255755/8M14
0.817441/255855/8M14
0.819441/265855/8M14
0.822445/870953/4M16
0.825445/8751003/4M16
0.829445/8751003/4M16
0.833485/8751003/4M16
0.836485/8751003/4M16
0.840483/4851107/8M20
0.843483/4851157/8M20
0.848483/4901207/8M20
0.8524127/81001251M24
0.8564127/81001351M24
0.85931211151451 1/8M27
0.86431611151451 1/8M27
0.8683161 1/81251601 1/4M30
0.8723201 1/81401701 1/4M30
0.8763201 1/41501851 3/8M33

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Class 300 Weld neck RTJ Flange Dimensions

Size in InchSize in mmOuter Dia.Flange ThicknessHub ODWeld Neck ODWelding Neck LengthRTJ RF DiaRTJ RF HeightPCDRTJ Pitch diaRTJ DepthRTJ WidthBore
ABCDEFGHIJKL
1/2159512.73821.351515.5466.734.145.547.14Welding Neck bore is derived from the pipe schedule
3/42011514.34826.75663.56.3582.642.886.358.74
12512515.95433.460706.3588.950.86.358.74
1 1/43213517.56442.26479.56.3598.460.336.358.74
1 1/24015519.17048.36790.56.35114.368.276.358.74
25016520.78460.3681087.9212782.557.9211.91
2 1/26519023.910073751277.92149.2101.67.9211.91
3802102711788.9781467.92168.3123.837.9211.91
3 1/29023028.6133101.6791597.92184.2131.787.9211.91
410025530.2146114.3841757.92200149.237.9211.91
512528033.4178141.3972107.92235180.987.9211.91
615032035206168.3972417.92269.9211.127.9211.91
820038039.7260219.11103027.92330.2269.887.9211.91
1025044546.13212731163567.92387.4323.857.9211.91
1230052049.3375323.81294137.92450.83817.9211.91
1435058552.4425355.61414577.92514.4419.17.9211.91
1640065055.6483406.41445087.92571.5469.97.9211.91
1845071058.85334571575757.92628.6533.47.9211.91
20500775625875081606359.53685.8584.29.5313.49
2460091568.370261016774911.13812.8692.1511.1316.66

Class 300 Weld neck RTJ Flange Stud & Bolt Dimensions

RTJ Root RadiusRing noDistance Between FlangesNo of BoltsBolt Size UNCMachine Bolt LengthRTJ Stud LengthHole SizeISO Stud Size
0.8R11341/255755/8M14
0.813445/865903/4M16
0.816445/865903/4M16
0.818445/870953/4M16
0.820443/4751007/8M20
0.823685/8751003/4M16
0.826683/4851157/8M20
0.831683/4901207/8M20
0.834683/4951257/8M20
0.837683/4951257/8M20
0.841683/41101357/8M20
0.8456123/41101407/8M20
0.8496127/81201501M24
0.85361611401701 1/8M27
0.8576161 1/81451851 1/4M30
0.8616201 1/81601901 1/4M30
0.8656201 1/41652051 3/8M33
0.8696241 1/41702101 3/8M33
1.5736241 1/41852201 3/8M33
1.5776241 1/22052551 5/8M39

Class 400 Weld neck RTJ Flange Dimensions

Size in InchSize in mmOuter Dia.Flange ThicknessHub ODWeld Neck ODWelding Neck LengthRTJ RF DiaRTJ RF HeightPCDRTJ Pitch diaRTJ DepthRTJ WidthBore
ABCDEFGHIJKL
1/2159514.33821.352515.5466.734.145.547.14Welding Neck bore is derived from the pipe schedule
3/42011515.94826.75763.56.3582.642.886.358.74
12512517.55433.462706.3588.950.86.358.74
1 1/43213520.76442.26779.56.3598.460.336.358.74
1 1/24015522.37048.37090.56.35114.368.276.358.74
25016525.48460.3731087.9212782.557.9211.9
2 1/26519028.610073791277.92149.2101.67.9211.9
38021031.811788.9831467.92168.3123.837.9211.9
3 1/29023035133101.6861597.92184.2131.787.9211.9
410025535146114.3891757.92200149.237.9211.91
512528038.1178141.31022107.92235180.987.9211.91
615032041.3206168.31032417.92269.9211.127.9211.91
820038047.7260219.11173027.92330269.887.9211.91
10250445543212731243567.92387.4323.857.9211.91
1230052057.2375323.81374137.92450.83817.9211.91
1435058560.4425355.61494577.92514.4419.17.9211.91
1640065063.5483406.41525087.92571.5469.97.9211.91
1845071066.75334571655757.92628.6533.47.9211.91
2050077569.95875081686359.53685.8584.29.5313.49
2460091576.270261017574911.13812.8692.1511.1316.66

Class 400 Weld neck RTJ Flange Stud & Bolt Dimensions

RTJ Root RadiusRing noDistance Between FlangesNo of BoltsBolt Size UNCRTJ Stud LengthHole SizeISO Stud Size
0.811341/2755/8M14
0.813445/8903/4M16
0.816445/8903/4M16
0.818445/8953/4M16
0.820443/41107/8M20
0.823585/81103/4M16
0.826583/41207/8M20
0.831583/41257/8M20
0.834587/81401M24
0.837687/81401M24
0.841687/81451M24
0.8456127/81501M24
0.84961211701 1/8M27
0.8536161 1/81901 1/4M30
0.8576161 1/42051 3/8M33
0.8616201 1/42101 3/8M33
0.8656201 3/82201 1/2M36
0.8696241 3/82301 1/2M36
1.5736241 1/22501 3/4M39
1.5776241 3/42801 7/8M45

Class 600 Weld neck RTJ Flange Dimensions

Size in InchSize in mmOuter Dia.Flange ThicknessHub ODWeld Neck ODWelding Neck LengthRTJ RF DiaRTJ RF HeightPCDRTJ Pitch diaRTJ DepthRTJ WidthBore
ABCDEFGHIJKL
1/2159514.33821.352515.5466.734.145.547.14Welding Neck bore is derived from the pipe schedule
3/42011515.94826.75763.56.3582.642.886.358.74
12512517.55433.462706.3588.950.86.358.74
1 1/43213520.76442.26779.56.3598.460.336.358.74
1 1/24015522.37048.37090.56.35114.368.276.358.74
25016525.48460.3731087.9212782.557.9211.91
2 1/26519028.610073791277.92149.2101.67.9211.91
38021031.811788.9831467.92168.3123.837.9211.91
3 1/29023035133101.6861597.92184.2131.787.9211.91
410027538.1152114.31021757.92215.9149.237.9211.91
512533044.5189141.31142107.92266.7180.987.9211.91
615035547.7222168.31172417.92292.1211.127.9211.91
820042055.6273219.11333027.92349.2269.887.9211.91
1025051063.53432731523567.92431.8323.857.9211.91
1230056066.7400323.81564137.924893817.9211.91
1435060569.9432355.61654577.92527419.17.9211.91
1640068576.2495406.41785087.92603.2469.97.9211.91
1845074582.65464571845757.92654533.47.9211.91
2050081588.96105081906359.53723.9584.29.5313.49
24600940101.671861020374911.13838.2692.1511.1316.66

Class 600 Weld neck RTJ Flange Stud & Bolt Dimensions

RTJ Root RadiusRing noDistance Between FlangesNo of BoltsBolt Size UNCRTJ Stud LengthHole SizeISO Stud Size
0.8R11341/2755/8M14
0.813445/8903/4M16
0.816445/8903/4M16
0.818445/8953/4M16
0.820443/41107/8M20
0.823585/81103/4M16
0.826583/41207/8M20
0.831583/41257/8M20
0.834587/81401M24
0.837587/81451M24
0.8415811651 1/8M27
0.84551211701 1/8M27
0.8495121 1/81951 1/4M30
0.8535161 1/42151 3/8M33
0.8575201 1/42201 3/8M33
0.8615201 3/82351 1/2M36
0.8655201 1/22551 5/8M39
0.8695201 5/82751 3/4M42
1.5735241 5/82901 3/4M42
1.5776241 7/83352M48

Class 900 Weld neck RTJ Flange Dimensions

Size in InchSize in mmOuter Dia.Flange ThicknessHub ODWeld Neck ODWelding Neck LengthRTJ RF DiaRTJ RF HeightPCDRTJ Pitch diaRTJ DepthRTJ WidthBore
ABCDEFGHIJKL
1/21512022.33821.36060.56.3582.639.676.358.74Welding Neck bore is derived from the pipe schedule
3/42013025.44426.77066.56.3588.944.456.358.74
12515028.65233.47371.56.35101.650.86.358.74
1 1/43216028.66442.273816.35111.160.336.358.74
1 1/24018031.87048.383926.35123.868.276.358.74
25021538.110560.31021247.92165.195.257.9211.91
2 1/26524541.3124731051377.92190.5107.957.9211.91
38024038.112788.91021567.92190.5123.837.9211.91
410029044.5159114.31141817.92235149.237.9211.91
512535050.8190141.31272167.92279.4180.987.9211.91
615038055.6235168.31402417.92317.5211.127.9211.91
820047063.5298219.11623087.92393.7269.887.9211.91
1025054569.93682731843627.92469.9323.857.9211.91
1230061079.4419323.82004197.92533.43817.9211.91
1435064085.8451355.621346711.13558.8419.111.1316.66
1640070588.9508406.421652411.13616469.911.1316.66
18450785101.656545722959412.7685.8533.412.719.84
2050085510862250824864812.7749.3584.212.719.84
246001040139.774961029277215.88901.7692.1515.8826.97

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Class 900 Weld neck RTJ Flange Stud & Bolt Dimensions

RTJ Root RadiusRing noDistance Between FlangesNo of BoltsBolt Size UNCRTJ Stud LengthHole SizeISO Stud Size
0.812443/41107/8M20
0.814443/41157/8M20
0.816447/81251M24
0.818447/81251M24
0.8204411401 1/8M27
0.824387/81451M24
0.8273811601 1/8M27
0.831487/81451M24
0.837481 1/81701 1/4M30
0.841481 1/41901 3/8M33
0.8454121 1/81951 1/4M30
0.8494121 3/82201 1/2M36
0.8534161 3/82351 1/2M36
0.8574201 3/82551 1/2M36
1.5624201 1/22801 5/8M39
1.5664201 5/82901 3/4M42
1.5705201 7/83352M48
1.57452023602 1/8M52
2.4786202 1/24552 5/8M64

Class 1500 Weld neck RTJ Flange Dimensions

Size in InchSize in mmOuter Dia.Flange ThicknessHub ODWeld Neck ODWelding Neck LengthRTJ RF DiaRTJ RF HeightPCDRTJ Pitch diaRTJ DepthRTJ WidthBore
ABCDEFGHIJKL
1/21512022.33821.36060.56.3582.639.676.358.74Welding Neck bore is derived from the pipe schedule
3/42013025.44426.77066.56.3588.944.456.358.74
12515028.65233.47371.56.35101.650.86.358.74
1 1/43216028.66442.273816.35111.160.336.358.74
1 1/24018031.87048.383926.35123.868.276.358.74
25021538.110560.31021247.92165.195.257.9211.91
2 1/26524541.3124731051377.92190.5107.957.9211.91
38026547.713388.91171687.92203.2136.537.9211.91
410031054162114.31241947.92241.3161.937.9211.91
512537573.1197141.31562297.92292.1193.687.9211.91
615039582.6229168.31712489.53317.5211.149.5313.49
820048592.1292219.121331811.13393.7269.8811.1316.66
1025058510836827325437111.13482.6323.8511.1316.66
12300675123.9451323.828343814.27571.538114.2723.01
14350750133.4495355.629848915.88635419.115.8826.97
16400825146.1552406.431154617.48704.8469.917.4830.18
1845091516259745732761317.48774.7533.417.4830.18
20500985177.864150835667317.48831.8584.217.4833.32
246001170203.276261040679420.62990.6692.1520.6236.53

Class 1500 Weld neck RTJ Flange Stud & Bolt Dimensions

RTJ Root RadiusRing noDistance Between FlangesNo of BoltsBolt Size UNCRTJ Stud LengthHole SizeISO Stud Size
0.812443/41107/8M20
0.814443/41157/8M20
0.816447/81251M24
0.818447/81251M24
0.8204411401 1/8M27
0.824387/81451M24
0.8273811601 1/8M27
0.835381 1/81801 1/4M30
0.839381 1/41951 3/8M33
0.844381 1/22501 5/8M39
1.5463121 3/82651 1/2M36
1.5504121 5/83251 3/4M42
1.5544121 7/83452M48
1.55851623852 1/8M52
2.4636162 1/44252 3/8M56
2.4678162 1/24702 5/8M64
2.4718162 3/45252 7/8M72
2.475101635653 1/8M76
2.47911163 1/26503 5/8M90

Class 2500 Weld neck RTJ Flange Dimensions

Size in InchSize in mmOuter Dia.Flange ThicknessHub ODWeld Neck ODWelding Neck LengthRTJ RF DiaRTJ RF HeightPCDRTJ Pitch diaRTJ DepthRTJ WidthBore
ABCDEFGHIJKL
1/21513530.24321.373656.3588.942.886.358.74Welding Neck bore is derived from the pipe schedule
3/42014031.85126.779736.3595.250.86.358.74
125160355733.48982.56.3510860.336.358.74
1 1/43218538.17342.2951027.92130.272.237.9211.91
1 1/24020544.57948.31111147.9214682.557.9211.91
25023550.99560.31271337.92171.4101.67.9211.91
2 1/26526557.2114731431499.53196.8111.139.5213.49
38030566.713388.91681689.53228.61279.5213.49
410035576.2165114.319020311.13273157.1811.1316.66
512542092.1203141.322924112.7323.8190.512.719.84
6150485108235168.327327912.7368.3228.612.719.84
8200550127305219.131834014.27438.2279.414.2723.01
10250675165.137527341942517.48539.8342.917.4830.18
12300760184.2441323.846449517.48619.1406.417.4833.32

Class 2500 Weld neck RTJ Flange Stud & Bolt Dimensions

RTJ Root RadiusRing noDistance Between FlangesNo of BoltsBolt Size UNCRTJ Stud LengthHole SizeISO Stud Size
0.813443/41207/8M20
0.816443/41257/8M20
0.818447/81401M24
0.8213411501 1/8M27
0.823341 1/81701 1/4M30
0.8263811801 1/8M27
1.528381 1/82051 1/4M30
1.532381 1/42301 3/8M33
1.538481 1/22601 5/8M39
1.542481 3/43101 7/8M45
1.5474823552 1/8M52
1.55151223952 1/8M52
2.4556122 1/25102 5/8M64
2.4608122 3/45602 7/8M72

Disclaimer –  Please check with ASME B16.5 Before using.

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