Stainless Steel Weld Neck Flange

  • Home /
  • Stainless Steel Weld Neck Flange

Looking for Weld Neck Flange manufacturers in India? Petromet Flange produces WNRF Flange in SS, Carbon Steel, Low Alloy, Nickel, Copper, and Titanium metal

What Is Weld Neck Flange?
A weld neck flange flange comes with a tapered hub/high hub, and it helps in relocating the stress to the pipes. It helps to bring a decrease in the high-stress concentration at the bottom of the given flange. There are basically two types of designs with the weld neck flanges- the first one is used with pipes while the other, which is the longer one, is used with process plants rather than the pipes. The weld neck flange consists of a round fitting that extends beyond the circumference rim. They are mostly manufactured through the process of forging, and are actually welded to the pipes. The rim consists of multiple holes which enables the given flange to get attached with a bolted flange. Due to the structural valve, this one is indeed an efficient design.
The weld neck flanges are made of different materials, however they should be specified by the quality standards of ASME or ASTM. The size and inner diameter of the flange can be customized according to the pipe to which the flange will be attached. Depending on the type of material used for making the flange, they are used for a wide range of conditions and temperatures.

What Is A Stainless Steel Weld Neck Flange Used For?
The Stainless Steel Weld Neck Flange can easily be distinguished from other flanges by their protruding neck. They have the same thickness and bevel as that of the pipe, where it will be installed. These flanges are ideally used in several critical situations, like applications in sub-zero temperature, elevated temperature, high pressure, wide fluctuations in temperature and/or pressure, or in case the pipe is bearing hazardous or expensive liquid. The weld neck flanges are often found in oil and gas pipelines, chemical industry, etc.

What Is A Carbon Steel Raised Face Weld Neck Flange?
The Raised Face Weld Neck Flange can be described as one of the most commonly used flanges used in various industries. They are easily recognizable due to their tapered hub, and are customized to match the dimensions of the pipe. Here the gasket face is located higher than the bolting surface, and the seal happens on the opposite of the hub side. Being made of carbon steel, the Raised Face Weld Neck Flange possesses some excellent features like improved corrosion resistance and durability. They also come with an excellent finish on the surface.

Difference Between Weld Neck Vs Long Weld Neck Flange
The weld neck flange consists of the weld prep located at the tip of the neck so that it can be welded to the matching pipe. Whereas, for long weld neck flanges,their nozzles in the ends are square cut, so that it can be used with the tank or for an alternate assembly.

Raised Face Weld Neck Flange Vs Reducing Weld Neck Flange
The Raised Face Weld Neck Flange is the most commonly used facing for the flange. It consist of a raised surface that is located above the bolting circle where the placement of the gasket will be made. They are widely used in oil and gas pipelines, as they can be used in environments that have both high and low temperatures.
The Reducing Weld Neck Flange is mainly used when there is a change in the size of the pipe. They are mainly used to change the size of the bore from a larger to a smaller bore. It helps to change the flow rate of the run pipe.

Stainless Steel Weld Neck Flange

Stainless Steel Weld Neck Flange

European Directive 2014/68/eu certified Stainless Steel Weld Neck Flange manufacturers in India is capable of distributing in excess of 1000 tonnes per annum, our online inventory includes ASTM A105N Flat Face Welding Neck Flange and Carbon Steel A694 Reducing Weld Neck Flange, call us for a fast quote!


Dimensions  ASME B16.5, ASME B16.47 Series A & B, MSS SP44
Size 1/2" to 48"
Class 300 LBS, 150 LBS, 900 LBS, 600 LBS, 1500 LBS, 2500 LBS
JIS 5K, 16 K 10 K, 20 K, 40 K, 30 K, 63 K
UNI 6Bar 16Bar 10Bar 25Bar 40Bar
Coating/Surface Treatment By Manufacturer Antirust Paint, Oil Black Paint, Yellow Transparent, Zinc Plated, Cold and Hot Dip Galvanized
EN 6Bar 25Bar 10Bar 40Bar 16Bar
BS BS4504 , BS4504, BS1560, BS10
Flanges Face Type Provided By Manufacturer RF (Raised Face), RTJ (Ring Type Joint)
Value Added Services CNC Machining, Customised Flanges
Making Methods Provided By Manufacturer Casting And Forging
Rolling And Cutting
Flanges Test Hydrostatic testing machine/ UI trasonic flaw detector/ X-ray detector/ Direct-reading Spectrograph/ Magnetic particle detector
Flanges Equipment Pushing Machine/ electric bevelling machine/ Press machine/ Bending machine/ Sand-blasting machine etc
Outer diameters 1/2” to 24”
Standards Provided By Manufacturer EN-1092, DIN, API7S-43, API605, B16.48, ISO70051, MSS S44, ANSI/ASME B16.5, B16.47 Series A & B, BS4504, BS 10, API7S-15, JISB2220, BS1560-3.1, ASME/ANSI B16.5/16.36/16.47A/16.47B, EN1092

Well know Stainless Steel Weld Neck Flange distributor, importer, stockists, wholesalers, stockholders, dealers, supplier, exporters and Manufacturer in Mumbai.

Stainless Steel ASTM A182 Gr. 304, 304L, 309, 316, 310, 316L, 317L, 321, 347, 904L
Duplex Steel ASTM A 182, ASME SA 182 UNS NO S31803, S32205. Werkstoff No. 1.4462
Copper Nickel Cupro Nickel 70/30 (C71500), Copper Nickel 90/10 (C70600 ), ASTM / ASME SB 62 / 151 / 61 / 152, UNS C71640
Carbon Steel High Yield CS ASTM A694 / A694 (F52 F56 F60 F65 F70 F80), A181 LF2, A105N, ASTM A350 LF2 / ASME SA350, ASTM/ASME A/SA105 A/SA105N & ASTM A105 / ASME SA105, P235GH, P245GH, P250GH, RST37.2, C22.8, S235JR, ST37, A516 Gr.70 A36, A694 F42, F46, F52, F60, F65, F706
Alloy Steel F11, F12, F5, F9, F22, F91
Nickel Alloy ASTM / ASME SB 564 UNS 4400 (MONEL 400 ), UNS 2200 ( NICKEL 200 ), UNS 8825 INCONEL (825), UNS 2201 (NICKEL 201 ), UNS 8020 ( ALLOY 20 / 20 CB 3, UNS 6601 ( INCONEL 601 ), UNS 6625 (INCONEL 625), UNS 6600 (INCONEL 600 ), UNS 10276 ( HASTELLOY C 276 )
Other Titanium, Aluminium, 254 SMO
NOMINAL BORE
Sch Sch Sch STD Sch Sch EXT Sch Sch Sch Sch Sch XX
Nom Pipe Size OD 10 20 30 Wall 40 60 Hvy 80 100 120 140 160 Hvy
½ 0.84 0.674 0.622 0.622 0.546 0.546 0.464 0.252
¾ 1.05 0.884 0.824 0.824 0.742 0.742 0.612 0.434
1 1.315 1.097 1.049 1.049 0.957 0.957 0.815 0.599
1 ¼ 1.66 1.442 1.38 1.38 1.278 1.278 1.16 0.896
1 ½ 1.9 1.682 1.61 1.61 1.5 1.5 1.338 1.1
2 2.375 2.157 2.067 2.067 1.939 1.939 1.687 1.503
2 ½ 2.875 2.635 2.469 2.469 2.323 2.323 2.125 1.771
3 3.5 3.26 3.068 3.068 2.9 2.9 2.624 2.3
3 ½ 4 3.76 3.548 3.548 3.364 3.364 2.728
4 4.5 4.26 4.026 4.026 3.826 3.826 3.624 3.438 3.152
5 5.563 5.295 5.047 5.047 4.813 4.813 4.563 4.313 4.063
6 6.625 6.357 6.065 6.065 5.761 5.761 5.501 5.187 4.897
8 8.625 8.329 8.125 8.071 7.981 7.981 7.813 7.625 7.625 7.437 7.187 7.001 6.813 6.875
10 10.75 10.42 10.25 10.136 10.02 10.02 9.75 9.75 9.562 9.312 9.062 8.75 8.5 8.75
12 12.75 12.39 12.25 12.09 12 11.938 11.626 11.75 11.374 11.062 10.75 10.5 10.126 10.75
14 14 13.5 13.376 13.25 13.25 13.124 12.812 13 12.5 12.124 11.812 11.5 11.188
16 16 15.5 15.376 15.25 15.25 15 14.688 15 14.312 13.938 13.562 13.124 12.812
18 18 17.5 17.376 17.124 17.25 16.876 16.5 17 16.124 15.688 15.25 14.876 14.438
20 20 19.5 19.25 19 19.25 18.812 18.376 19 17.938 17.438 17 16.5 16.062
22 22 21.5 21.25 21
24 24 23.5 23.25 22.876 23.25 22.624 22.062 23 21.562 20.938 20.376 19.876 19.312
26 26 25.25 25
30 30 29.376 29 28.75 29.25 29
36 36 35.376 35 34.75 35.25 34.5 35
40 40 39.25 39
42 42 41.25 41
48 48 47.25 47

Why don't you directly contact a Weld Neck Flanges manufacturers in India? Supplier of Carbon Steel Long Weld Neck Flange and ASTM A350 LF2 WNFF flange offers nondestructive (NDT) method

NPS NO OF
BOLT
HOLES
DIA
STUD
BOLTS
LENGTH
STUD
BOLTS
1/2 4 1/2 2.25
3/4 4 1/2 2.5
1 4 1/2 2.5
1.1/4 4 1/2 2.75
1.1/2 4 1/2 2.75
2 4 5/8 3.25
2.1/2 4 5/8 3.5
3 4 5/8 3.5
3.1/2 8 5/8 3.5
4 8 5/8 3.5
5 8 3/4 3.75
6 8 3/4 4
8 8 3/4 4.25
10 12 7/8 4.5
12 12 7/8 4.75
14 12 1 5.25
16 16 1 5.25
18 16 1.1/8 5.75
20 20 1.1/8 6.25
24 20 1.1/4 6.75
NOMINAL SIZE DIMENSIONS WEIGHT (KG)
NPS
(Inches)
DN (mm) FLANGE
MM
FLANGE
THICKNESS
SOW
SW
WN BLIND
1/2 15 88.9 11.2 0.4 0.5 0.4
3/4 20 98.6 12.7 0.6 0.7 0.6
1 25 108 14.2 0.8 1 0.9
1 1/4 32 117.3 15.7 1 1.3 1.2
1 1/2 40 127 17.5 1.3 1.7 1.5
2 50 152.4 19.1 2.1 2.6 2.4
2 1/2 65 177.8 22.4 3.3 4.1 3.9
3 80 190.5 23.9 3.9 4.9 4.9
3 1/2 90 215.9 23.9 4.8 6.1 6.2
4 100 228.6 23.9 5.3 6.8 7.0
5 125 254 23.9 6.1 8.6 8.6
6 150 279.4 25.4 7.5 10.6 11.3
8 200 342.9 28.4 12.1 17.6 19.6
10 250 406.4 30.2 16.5 24 28.6
12 300 482.6 31.8 26.2 36.5 43.2
14 350 533.4 35.1 34.6 48.4 58.1
16 400 596.9 36.6 44.8 60.6 76.1
18 450 635 39.6 48.9 68.3 93.7
20 500 698.5 42.9 61.9 84.5 122.0
24 600 812.8 47.8 86.9 115 185.0
Stainless Steel Weld Neck Flange Price Per Piece in India Carbon Steel WNRF Flanges Price in INR Long Weld Neck Flange Price in UAE Dirham ASTM A105N Flat Face Welding Neck Flanges Price in USD
STAINLESS STEEL 304 Flange WN 150 RF 20B462 40/S BORE ITEM FLANGE-TYPE-WELD NECK Per Kg 811 UAE Dirham 40.30 $10.97
ANSI B16.5 SA182 F316 DN 20, 300#SCH 40S, WELD NECK RF Per Kg 476 UAE Dirham 23.65 $6.44
CARBON STEEL A105 300#RF STL STD BORE WELD NECK Flanges -ASME CLASS 300 Facing -RAISED FACE Per Kg 165 UAE Dirham 8.20 $2.23
WELD NECK CARBON STEEL FLANGES LF2 Per Kg 491 UAE Dirham 24.40 $6.64

Are you looking for Weld Neck Flange manufacturers in India, Contact us to get latest price list of ASTM A105N Flat Face Welding Neck Flange. We are leading Carbon Steel A694 Reducing Weld Neck Flange supplier and exporter in various countries.

Buy rf/ ff/ rtj face ASTM A182 F304 Welding Neck Flange, ASTM A105 WNRF Flange and A182 F316 Raised Face Weld Neck Flange at Unbeatable Prices in India

EN 1092-1 TYPE 11 Weld Neck Flange

Rated Diameter Flange Neck Raised face Screws Weight
(7,85 Kg/dm3)
d1 k D b h1 d3 s r h2 d4 f d2 Thread Bolt holes Kg
15 21,3 65 95 16 38 32 2,00 4 6 45 2 14 M12 4 0,678
20 26,9 75 105 18 40 40 2,30 4 6 58 2 14 M12 4 0,768
25 33,7 85 115 18 40 46 2,60 4 6 68 2 14 M12 4 1,090
32 42,4 100 140 18 42 56 2,60 6 6 78 2 18 M16 4 1,300
40 48,3 110 150 18 45 64 2,60 6 7 88 3 18 M16 4 1,910
50 60,3 125 165 18 45 74 2,9 6 8 102 3 18 M16 4 2,530
65 76,1 145 185 18 45 92 2,9 6 10 122 3 18 M16 4 3,030
80 88,9 160 200 20 50 105 3,2 6 10 138 3 18 M16 8 3,920
100 114,3 180 220 20 52 131 3,6 8 12 158 3 18 M16 8 4,620
125 139,7 210 250 22 55 156 4,0 8 12 188 3 18 M16 8 6,300
150 168,3 240 285 22 55 184 4,5 10 12 212 3 22 M20 8 7,810
200 219,1 295 340 24 62 235 6,30 10 16 268 3 22 M20 12 11,500
250 273,0 355 405 26 70 292 6,30 12 16 320 3 26 M24 12 16,700
300 323,9 410 460 28 78 344 7,10 12 16 378 4 26 M24 12 22,100
350 355,6 470 520 30 82 390 8,00 12 16 438 4 26 M24 16 32,800
400 406,4 525 580 32 85 445 8,00 12 16 490 4 30 M27 16 41,100
450 457,0 585 640 34 83 490 8,00 12 16 550 4 30 M27 20 48,500
500 508 650 715,0 36 84 548 8,0 12 16 610 4 33 M30 20 63,400
600 610 770 840,0 40 88 670 10,0 12 18 725 5 36 M33 20 96,000
700 711 840 910,0 40 104 755 10,0 12 18 795 5 36 M33 24 96,500
800 813 950 1025,0 41 108 855 12,5 12 20 900 5 39 M36 24 122,000
900 914 1050 1125,0 48 118 955 12,5 12 20 1000 5 39 M36 28 155,000
1000 1016 1170 1255,0 59 137 1058 12,5 16 22 1115 5 42 M39 28 233,000
1200 1219 1390 1485,0 78 160 1262 14,2 16 30 1330 5 48 M45 32 390,000
1400 1422 1590 1685,0 84 177 1465 16,0 16 30 1530 5 48 M45 36 495,000
1600 1626 1820 1930,0 102 204 1668 17,5 16 35 1750 5 56 M52 40 760,000
1800 1829 2020 2130,0 110 218 1870 20,0 16 35 1950 5 56 M52 44 929,000
2000 2032 2230 2345,0 124 238 2072 22,0 16 40 2150 5 62 M56 48 1.185,000

These flanges are bored to match the inside diameter of the matching pipe or fitting, ensuring that product flow is not restricted. This lowers erosion by preventing turbulence at the junction. Through the tapered hub, they also provide good stress distribution. With a single full penetration, V weld, this flange will be welded to a pipe or fitting.

Manufacturing Process Of Weld Neck Flange

Stainless Steel Weld Neck Flange

Stainless Steel Weld Neck Flange

Carbon Steel Weld Neck Flange

Carbon Steel Weld Neck Flange

Titanium WNFF Flange

Titanium WNFF Flange

Inconel Weld Neck Orifice Flange

Inconel Weld Neck Orifice Flange

316 Stainless Steel Welding Neck Flange

316 Stainless Steel Welding Neck Flange

Alloy Steel Reducing Weld Neck Flange

Alloy Steel Reducing Weld Neck Flange

Mild Steel Weld Neck Flange

Mild Steel Weld Neck Flange

Gi Raised Face Weld Neck Flange

Gi Raised Face Weld Neck Flange

ASTM A350 LF2 WNRF Flange

ASTM A350 LF2 WNRF Flange

Aluminum Flat Face Weld Neck Flange

Aluminum Flat Face Weld Neck Flange

Nickel Alloy WNRF Flange

Nickel Alloy WNRF Flange

A182 F11 Weld Neck Flange

A182 F11 Weld Neck Flange

Copper Welding Neck Flange

Copper Welding Neck Flange

Hastelloy Long Weld Neck Flange

Hastelloy Long Weld Neck Flange

Stainless Steel 304 WNRF Flange

Stainless Steel 304 WNRF Flange

ASTM A182 F304 LWNRF Flange

ASTM A182 F304 LWNRF Flange

Duplex LWNRF Flange

Duplex LWNRF Flange

Super Duplex WNRF Flange

Super Duplex WNRF Flange

ASTM A516 Gr.70 Rtj Weld Neck Flange

ASTM A516 Gr.70 Rtj Weld Neck Flange

UNS S31803 WNFF Flange

UNS S31803 WNFF Flange

Ductile Iron Weld Neck Pipe Flanges

Ductile Iron Weld Neck Pipe Flanges

Alloy Steel Long Weld Neck Flange

Alloy Steel Long Weld Neck Flange

ASTM A182 F316 Long Welding Neck Flange

ASTM A182 F316 Long Welding Neck Flange

ASTM A105 Weld Neck Orifice Flange

ASTM A105 Weld Neck Orifice Flange

  • Manufacturer logo
  • Material Grade
  • ASTM material code
  • Heat No
  • Service rating (Pressure-temperature Class))
  • Size
  • Thickness (Schedule)
  • Special marking if any QT
Check , MS Weld Neck Orifice Flange, Alloy Steel Long Welding Neck Flange, and A182 Gr F11 Weld Neck Pipe Flanges thickness & price in India

Long Weld Neck Flange

Size in Inch Size in mm Outer Dia. Flanges Thick. Hub OD Weld Neck OD RF Dia. RF Height PCD Hub Length No of Bolts Bolt Size UNC Machine Bolt Length RF Stud Length Hole Size ISO Stud Size
A B C D E F G H
1/2 15 90 9.6 30 21.3 34.9 2 60.3 As Required 4 1/2 50 55 5/8 M14
3/4 20 100 11.2 38 26.7 42.9 2 69.9 As Required 4 1/2 50 65 5/8 M14
1 25 110 12.7 49 33.4 50.8 2 79.4 As Required 4 1/2 55 65 5/8 M14
1 1/4 32 115 14.3 59 42.2 63.5 2 88.9 As Required 4 1/2 55 70 5/8 M14
1 1/2 40 125 15.9 65 48.3 73 2 98.4 As Required 4 1/2 65 70 5/8 M14
2 50 150 17.5 78 60.3 92.1 2 120.7 As Required 4 5/8 70 85 3/4 M16
2 1/2 65 180 20.7 90 73 104.8 2 139.7 As Required 4 5/8 75 90 3/4 M16
3 80 190 22.3 108 88.9 127 2 152.4 As Required 4 5/8 75 90 3/4 M16
3 1/2 90 215 22.3 122 101.6 139.7 2 177.8 As Required 8 5/8 75 90 3/4 M16
4 100 230 22.3 135 114.3 157.2 2 190.5 As Required 8 5/8 75 90 3/4 M16
5 125 255 22.3 164 141.3 185.7 2 215.9 As Required 8 3/4 85 95 7/8 M20
6 150 280 23.9 192 168.3 215.9 2 241.3 As Required 8 3/4 85 100 7/8 M20
8 200 345 27 246 219.1 269.9 2 298.5 As Required 8 3/4 90 110 7/8 M20
10 250 405 28.6 305 273 323.8 2 362 As Required 12 7/8 100 115 1 M24
12 300 485 30.2 365 323.8 381 2 431.8 As Required 12 7/8 100 120 1 M24
14 350 535 33.4 400 355.6 412.8 2 476.3 As Required 12 1 115 135 1 1/8 M27
16 400 595 35 457 406.4 469.9 2 539.8 As Required 16 1 115 135 1 1/8 M27
18 450 635 38.1 505 457.2 533.4 2 577.9 As Required 16 1 1/8 125 145 1 1/4 M30
20 500 700 41.3 559 508 584.2 2 635 As Required 20 1 1/8 140 160 1 1/4 M30
24 600 815 46.1 663 610 692.2 2 749.3 As Required 20 1 1/4 150 170 1 3/8 M33
NPS DN FLANGES OD FLANGES THICKNESS D LONG WELD NECK FLANGES WEIGHT (KGS)
(Inches) (mm) A MM MM  
1/2 15 88.9 11.2 0.5
3/4 20 98.6 12.7 0.7
1 25 108 14.2 1
1 1/ 4 32 117.3 15.7 1.3
1 1/ 2 40 127 17.5 1.7
2 50 152.4 19.1 2.6
2 1/ 2 65 177.8 22.4 4.1
3 80 190.5 23.9 4.9
3 1/ 2 90 215.9 23.9 6.1
4 100 228.6 23.9 6.8
5 125 254 23.9 8.6
6 150 279.4 25.4 10.6
8 200 342.9 28.4 17.6
10 250 406.4 30.2 24
12 300 482.6 31.8 36.5
14 350 533.4 35.1 48.4
16 400 596.9 36.6 60.6
18 450 635 39.6 68.3
20 500 698.5 42.9 84.5
24 600 812.8 47.8 115

Class 150 Weld Neck Flange Dimensions

Size in Inch Size in mm Outer Diameter Flange Thickness Hub OD Weld Neck OD Welding Neck Length Bore RF Diameter RF Height PCD Weld Face
A B C D E F G H I J
1/2 15 90 9.6 30 21.3 46 Welding Neck bore is derived from the pipe schedule 34.9 2 60.3 1.6
3/4 20 100 11.2 38 26.7 51 42.9 2 69.9 1.6
1 25 110 12.7 49 33.4 54 50.8 2 79.4 1.6
1 1/4 32 115 14.3 59 42.2 56 63.5 2 88.9 1.6
1 1/2 40 125 15.9 65 48.3 60 73 2 98.4 1.6
2 50 150 17.5 78 60.3 62 92.1 2 120.7 1.6
2 1/2 65 180 20.7 90 73 68 104.8 2 139.7 1.6
3 80 190 22.3 108 88.9 68 127 2 152.4 1.6
3 1/2 90 215 22.3 122 101.6 70 139.7 2 177.8 1.6
4 100 230 22.3 135 114.3 75 157.2 2 190.5 1.6
5 125 255 22.3 164 141.3 87 185.7 2 215.9 1.6
6 150 280 23.9 192 168.3 87 215.9 2 241.3 1.6
8 200 345 27 246 219.1 100 269.9 2 298.5 1.6
10 250 405 28.6 305 273 100 323.8 2 362 1.6
12 300 485 30.2 365 323.8 113 381 2 431.8 1.6
14 350 535 33.4 400 355.6 125 412.8 2 476.3 1.6
16 400 595 35 457 406.4 125 469.9 2 539.8 1.6
18 450 635 38.1 505 457.2 138 533.4 2 577.9 1.6
20 500 700 41.3 559 508 143 584.2 2 635 1.6
24 600 815 46.1 663 610 151 692.2 2 749.3 1.6

300 Lb Weld Neck Flange Dimensions

Size in Inch Size in mm Outer Diameter Flange Thickness Hub OD Weld Neck OD Welding Neck Length Bore RF Diameter RF Height PCD Weld Face
A B C D E F G H I J
1/2 15 95 12.7 38 21.3 51 Welding Neck bore is derived from the pipe schedule 34.9 2 66.7 1.6
3/4 20 115 14.3 48 26.7 56 42.9 2 82.6 1.6
1 25 125 15.9 54 33.4 60 50.8 2 88.9 1.6
1 1/4 32 135 17.5 64 42.2 64 63.5 2 98.4 1.6
1 1/2 40 155 19.1 70 48.3 67 73 2 114.3 1.6
2 50 165 20.7 84 60.3 68 92.1 2 127 1.6
2 1/2 65 190 23.9 100 73 75 104.8 2 149.2 1.6
3 80 210 27 117 88.9 78 127 2 168.3 1.6
3 1/2 90 230 28.6 133 101.6 79 139.7 2 184.2 1.6
4 100 255 30.2 146 114.3 84 157.2 2 200 1.6
5 125 280 33.4 178 141.3 97 185.7 2 235 1.6
6 150 320 35 206 168.3 97 215.9 2 269.9 1.6
8 200 380 39.7 260 219.1 110 269.9 2 330.2 1.6
10 250 445 46.1 321 273 116 323.8 2 387.4 1.6
12 300 520 49.3 375 323.8 129 381 2 450.8 1.6
14 350 585 52.4 425 355.6 141 412.8 2 514.4 1.6
16 400 650 55.6 483 406.4 144 469.9 2 571.5 1.6
18 450 710 58.8 533 457 157 533.4 2 628.6 1.6
20 500 775 62 587 508 160 584.2 2 685.8 1.6
24 600 915 68.3 702 610 167 692.2 2 812.8 1.6

Class 400 Weld Neck Flange Dimensions

Size in Inch Size in mm Outer Diameter Flange Thickness Hub OD Weld Neck OD Welding Neck Length Bore RF Diameter RF Height PCD Weld Face
A B C D E F G H I J
1/2 15 95 14.3 38 21.3 52 Welding Neck bore is derived from the pipe schedule 34.9 7 66.7 1.6
3/4 20 115 15.9 48 26.7 57 42.9 7 82.6 1.6
1 25 125 17.5 54 33.4 62 50.8 7 88.9 1.6
1 1/4 32 135 20.7 64 42.2 67 63.5 7 98.4 1.6
1 1/2 40 155 22.3 70 48.3 70 73 7 114.3 1.6
2 50 165 25.4 84 60.3 73 92.1 7 127 1.6
2 1/2 65 190 28.6 100 73 79 104.8 7 149.2 1.6
3 80 210 31.8 117 88.9 83 127 7 168.3 1.6
3 1/2 90 230 35 133 101.6 86 139.7 7 184.2 1.6
4 100 255 35 146 114.3 89 157.2 7 200 1.6
5 125 280 38.1 178 141.3 102 185.7 7 235 1.6
6 150 320 41.3 206 168.3 103 215.9 7 269.9 1.6
8 200 380 47.7 260 219.1 117 269.9 7 330 1.6
10 250 445 54 321 273 124 323.8 7 387.4 1.6
12 300 520 57.2 375 323.8 137 381 7 450.8 1.6
14 350 585 60.4 425 355.6 149 412.8 7 514.4 1.6
16 400 650 63.5 483 406.4 152 469.9 7 571.5 1.6
18 450 710 66.7 533 457 165 533.4 7 628.6 1.6
20 500 775 69.9 587 508 168 584.2 7 685.8 1.6
24 600 915 76.2 702 610 175 692.2 7 812.8 1.6

600# Weld Neck Flange Dimensions

Size in Inch Size in mm Outer Diameter Flange Thickness Hub OD Weld Neck OD Welding Neck Length Bore RF Diameter RF Height PCD Weld Face
A B C D E F G H I J
1/2 15 95 14.3 38 21.3 52 Welding Neck bore is derived from the pipe schedule 34.9 7 66.7 1.6
3/4 20 115 15.9 48 26.7 57 42.9 7 82.6 1.6
1 25 125 17.5 54 33.4 62 50.8 7 88.9 1.6
1 1/4 32 135 20.7 64 42.2 67 63.5 7 98.4 1.6
1 1/2 40 155 22.3 70 48.3 70 73 7 114.3 1.6
2 50 165 25.4 84 60.3 73 92.1 7 127 1.6
2 1/2 65 190 28.6 100 73 79 104.8 7 149.2 1.6
3 80 210 31.8 117 88.9 83 127 7 168.3 1.6
3 1/2 90 230 35 133 101.6 86 139.7 7 184.2 1.6
4 100 275 38.1 152 114.3 102 157.2 7 215.9 1.6
5 125 330 44.5 189 141.3 114 185.7 7 266.7 1.6
6 150 355 47.7 222 168.3 117 215.9 7 292.1 1.6
8 200 420 55.6 273 219.1 133 269.9 7 349.2 1.6
10 250 510 63.5 343 273 152 323.8 7 431.8 1.6
12 300 560 66.7 400 323.8 156 381 7 489 1.6
14 350 605 69.9 432 355.6 165 412.8 7 527 1.6
16 400 685 76.2 495 406.4 178 469.9 7 603.2 1.6
18 450 745 82.6 546 457 184 533.4 7 654 1.6
20 500 815 88.9 610 508 190 584.2 7 723.9 1.6
24 600 940 101.6 718 610 203 692.2 7 838.2 1.6

900# Weld Neck Flanges Dimensions

Size in Inch Size in mm Outer Diameter Flange Thickness Hub OD Weld Neck OD Welding Neck Length Bore RF Diameter RF Height PCD Weld Face
A B C D E F G H I J
1/2 15 120 22.3 38 21.3 60 Welding Neck bore is derived from the pipe schedule 34.9 7 82.6 1.6
3/4 20 130 25.4 44 26.7 70 42.9 7 88.9 1.6
1 25 150 28.6 52 33.4 73 50.8 7 101.6 1.6
1 1/4 32 160 28.6 64 42.2 73 63.5 7 111.1 1.6
1 1/2 40 180 31.8 70 48.3 83 73 7 123.8 1.6
2 50 215 38.1 105 60.3 102 92.1 7 165.1 1.6
2 1/2 65 245 41.3 124 73 105 104.8 7 190.5 1.6
3 80 240 38.1 127 88.9 102 127 7 190.5 1.6
4 100 290 44.5 159 114.3 114 157.2 7 235 1.6
5 125 350 50.8 190 141.3 127 185.7 7 279.4 1.6
6 150 380 55.6 235 168.3 140 215.9 7 317.5 1.6
8 200 470 63.5 298 219.1 162 269.9 7 393.7 1.6
10 250 545 69.9 368 273 184 323.8 7 469.9 1.6
12 300 610 79.4 419 323.8 200 381 7 533.4 1.6
14 350 640 85.8 451 355.6 213 412.8 7 558.8 1.6
16 400 705 88.9 508 406.4 216 469.9 7 616 1.6
18 450 785 101.6 565 457 229 533.4 7 685.8 1.6
20 500 855 108 622 508 248 584.2 7 749.3 1.6
24 600 1040 139.7 749 610 292 692.2 7 901.7 1.6

Class 1500 Weld Neck Flange Dimensions

Size in Inch Size in mm Outer Diameter Flange Thickness Hub OD Weld Neck OD Welding Neck Length Bore RF Diameter RF Height PCD Weld Face
A B C D E F G H I J
1/2 15 120 22.3 38 21.3 60 Welding Neck bore is derived from the pipe schedule 34.9 7 82.6 1.6
3/4 20 130 25.4 44 26.7 70 42.9 7 88.9 1.6
1 25 150 28.6 52 33.4 73 50.8 7 101.6 1.6
1 1/4 32 160 28.6 64 42.2 73 63.5 7 111.1 1.6
1 1/2 40 180 31.8 70 48.3 83 73 7 123.8 1.6
2 50 215 38.1 105 60.3 102 92.1 7 165.1 1.6
2 1/2 65 245 41.3 124 73 105 104.8 7 190.5 1.6
3 80 265 47.7 133 88.9 117 127 7 203.2 1.6
4 100 310 54 162 114.3 124 157.2 7 241.3 1.6
5 125 375 73.1 197 141.3 156 185.7 7 292.1 1.6
6 150 395 82.6 229 168.3 171 215.9 7 317.5 1.6
8 200 485 92.1 292 219.1 213 269.9 7 393.7 1.6
10 250 585 108 368 273 254 323.8 7 482.6 1.6
12 300 675 123.9 451 323.8 283 381 7 571.5 1.6
14 350 750 133.4 495 355.6 298 412.8 7 635 1.6
16 400 825 146.1 552 406.4 311 469.9 7 704.8 1.6
18 450 915 162 597 457 327 533.4 7 774.7 1.6
20 500 985 177.8 641 508 356 584.2 7 831.8 1.6
24 600 1170 203.2 762 610 406 692.2 7 990.6 1.6

2500# Weld Neck Flange Dimensions

Size in Inch Size in mm Outer Diameter Flange Thickness Hub OD Weld Neck OD Welding Neck Length Bore RF Diameter RF Height PCD Weld Face
A B C D E F G H I J
1/2 15 135 30.2 43 21.3 73 Welding Neck bore is derived from the pipe schedule 34.9 7 88.9 1.6
3/4 20 140 31.8 51 26.7 79 42.9 7 95.2 1.6
1 25 160 35 57 33.4 89 50.8 7 108 1.6
1 1/4 32 185 38.1 73 42.2 95 63.5 7 130.2 1.6
1 1/2 40 205 44.5 79 48.3 111 73 7 146 1.6
2 50 235 50.9 95 60.3 127 92.1 7 171.4 1.6
2 1/2 65 265 57.2 114 73 143 104.8 7 196.8 1.6
3 80 305 66.7 133 88.9 168 127 7 228.6 1.6
4 100 355 76.2 165 114.3 190 157.2 7 273 1.6
5 125 420 92.1 203 141.3 229 185.7 7 323.8 1.6
6 150 485 108 235 168.3 273 215.9 7 368.3 1.6
8 200 550 127 305 219.1 318 269.9 7 438.2 1.6
10 250 675 165.1 375 273 419 323.8 7 539.8 1.6
12 300 760 184.2 441 323.8 464 381 7 619.1 1.6
  • A long, conical neck, the end of which is welded to the pipe, distinguishes these flanges.
  • The pipe's internal diameter is the same as the flange's, resulting in a generally continuous sectional flow in the gases/liquids circulating through the pipe with no interruptions or turbulence.
  • Neck flanges for welding give good structural strength and stress distribution.
  • Another element to consider is the junction between the neck and the tube it is welded to, which must be carefully inspected to avoid turbulence in high-speed flows.
  • Oil And Gas Industry
  • Paper & Pulp
  • Refineries
  • Fossil Fuel Power Plants
  • Ship Building
  • Nuclear Power
  • Power Plants
  • Marine Applications
Inside Diameter 10” and smaller ±1/32”
12” through 18” + 1/16”
20” and larger +1/8”, -1/16”
Outside Diameter* When OD is 24” or less ±1/16”
When OD is over 24” ± 1/8”
Diameter of Contact Face 1/16” Raised Face ±1/32”
1/4” Raised Face Tongue and Groove or Male and Female ±1/64”
Diameter of Hub at Point of Welding 5” and smaller +3/32”, -1/32”
6” and larger +5/32”, -1/32”
Welding Bevel Standards see drawings on Page 78
Drilling* Bolt Circle ±1/16”
Bolt hole spacing +1/32”
Eccentricity of Bolt Circle and Facing (with respect to bore) 1/32” max
Diameter of Hub at Base* When Hub Base is 24” or less ±1/16”
When Hub Base is over 24” ±1/8”
Thickness 18” and smaller +1/8”, -0”
20” and larger +3/16”, -0”
Where allowance has been left on face for finish. All sizes* +1/8”, -1/16”
Length Thru Hub 10” and smaller ±1/16”
12” and larger ±1/8”