Weld Neck Flange

What is weld neck flange?

The weld neck flange,abbreviated as WNF,is one of the most used flange types and it has a neck for welding with the pipe.Weld neck flange is easily to recognized by their long tapered neck(the neck also called hub),and the tapered neck can supply a high strength reinforcement to support flange and pipe.Weld neck flange is suitable to used in high pressure and extremely temperature situation.

ANSI B16.5 A105N RTJ weld neck flanges

There are two types of weld neck flange:regular weld neck flange and long weld neck flange.Regular weld neck flange is used with butt welding pipe fittings and connect the two pieces of pipe together.Long weld neck flange is usually used with equipment and vessel nozzles and it is rarely used with pipe.

The design of weld neck flange allows for a full penetration weld at its base where it connects to the pipe.This weld can be X-ray inspected for quality control.

Specification of weld neck flange:

ANSI/ASME standard:

• ANSI/ASME B16.5 class 150 weld neck flange dimensions: ½”-24″
• ANSI/ASME B16.5 class 300 weld neck flange dimensions: ½”-24″
• ANSI/ASME B16.5 class 300 weld neck flange dimensions: ½”-24″
• ANSI/ASME B16.5 class 400 weld neck flange dimensions: ½”-24″
• ANSI/ASME B16.5 class 600 weld neck flange dimensions: ½”-24″
• ANSI/ASME B16.5 class 900 weld neck flange dimensions: ½”-24″
• ANSI/ASME B16.5 class 1500 weld neck flange dimensions: ½”-24″
• ANSI/ASME B16.5 class 2500 weld neck flange dimensions: ½”-12″
• ANSI/ASME B16.47 series A class 150 weld neck flange dimensions: 26″-48″
• ANSI/ASME B16.47 series A class 300 weld neck flange dimensions: 26″-48″
• ANSI/ASME B16.47 series A class 400 weld neck flange dimensions: 26″-48″
• ANSI/ASME B16.47 series A class 600 weld neck flange dimensions: 26″-48″
• ANSI/ASME B16.47 series A class 900 weld neck flange dimensions: 26″-48″
• ANSI/ASME B16.47 series B class 75 weld neck flange dimensions: 26″-48″
• ANSI/ASME B16.47 series B class 150 weld neck flange dimensions: 26″-48″
• ANSI/ASME B16.47 series B class 300 weld neck flange dimensions: 26″-48″
• ANSI/ASME B16.47 series B class 400 weld neck flange dimensions: 26″-36″
• ANSI/ASME B16.47 series B class 600 weld neck flange class dimensions: 26″-36″
• ANSI/ASME B16.47 series B class 900 weld neck flange class dimensions: 26″-36″

DIN standard:

• DIN 2631 PN6 weld neck flange: DN15-DN3600
• DIN 2632 PN10 weld neck flange: DN10-DN3000
• DIN2633 PN16 weld neck flange: DN10-DN2000
• DIN2634 PN25 weld neck flange: DN10-DN1000
• DIN2635 PN40 weld neck flange: DN10-DN500
• DIN2636 PN64 weld neck flange: DN10-DN400
• DIN2637 PN100 weld neck flange: DN10-DN350
• DIN2638 PN6 weld neck flange: DN10-DN300

EN standard:

• EN 1092-1 PN6 weld neck flange: DN10-DN2000
• EN 1092-1 PN10 weld neck flange: DN10-DN2000
• EN 1092-1 PN16 weld neck flange: DN10-DN2000
• EN 1092-1 PN25 weld neck flange: DN10-DN1000
• EN 1092-1 PN40 weld neck flange: DN10-DN600

JIS standard

• JIS B2220 10K weld neck flange: 10A-600A
• JIS B2220 20K weld neck flange: 10A-600A
• JIS B2220 30K weld neck flange: 15A-400A
• JIS B2220 40K weld neck flange: 15A-400A
• JIS B2220 63K weld neck flange: 15A-400A

long weld neck flanges

Materials of weld neck flange:

Haihao Group manufacture weld neck flanges with various materials,such as carbon steel,stainless steel and alloy steel.

Carbon steel weld neck flange:

• ASTM A105 weld neck flange
• ASTM A350 LF2 weld neck flange
• SS400 weld neck flange
• P235GH weld neck flange
• P250GH weld neck flange
• C22.8 weld neck flange
• Q235 weld neck flange

Stainless steel weld neck flange:

• ASTM A182 F304 weld neck flange
• ASTM A182 F304L weld neck flange
• ASTM A182 F316 weld neck flange
• ASTM A182 F316L weld neck flange
• ASTM A182 F321 weld neck flange
• ASTM A182 F347 weld neck flange

Alloy steel weld neck flange:

• ASTM A694 F42 weld neck flange
• ASTM A694 F46 weld neck flange
• ASTM A694 F52 weld neck flange
• ASTM A694 F56 weld neck flange
• ASTM A694 F60 weld neck flange
• ASTM A694 F65 weld neck flange
• ASTM A694 F70 weld neck flange
• ASTM A182 F5 weld neck flange
• ASTM A182 F9 weld neck flange
• ASTM A182 F11 weld neck flange
• ASTM A182 F12 weld neck flange
• ASTM A182 F22 weld neck flange
• ASTM A182 F91 weld neck flange

Sealing face of weld neck flange:

With a neck on one side of the flange, the other side of the flange is sealing face,which are between the two flanges joint.WN flange usually supplied with flat face (FF),raised face(RF) and ring type joint (RTJ). The raised face has a height on the flange rather than the flat face,the RTJ face is used to contain the gasket ring which are specially for high pressure application.

Haihao Group are specialized in the production of forged flanges,our forged flange products as follows:

Weld Neck Flange	Blind Flange	Slip On Flange	Plate Flange
Socket Weld Flange	Threaded Flange	Lap Joint Flange	Long Weld Neck Flange
Orifice flange	Spectacle Blind Flange	Nipoflange	Reducing Flange
Anchor Flanges	Large Diameter Flange	Tubesheet	Non-standard Flange

Haihao Group are specialized in the production of forged flanges,our products are widely used in the following industries: oil,gas,chemical,shipbuilding,water treatment,power plant,steam,construction and other field.If you want to know more about our piping products,please email us:sales@haihaogroup.com