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What is a Flange?


Forged Flanges are perfectly finished with precision using the latest machinery.

Forged flange is the best mechanical properties of a flange product, its raw materials are generally tube, and then after cutting and then continue to beat, to eliminate the ingot in the segregation, loose and other defects.

ANSI flange

ASME/ANSI Flange types differ in shape, size range and connection method.

The main types of standard flanges are listed below:

Welding Neck Flanges

A weld neck flange ("WN") has a long tapered hub that can be welded with a pipe or a fitting and is normally used in high pressure and low or high temperatures applications.


Blind flanges do not have a center hole, differently from all other types of flanges seen above, and are used to seal a pipeline, or a valve / pressure vessel and prevent flow. Blind flanges have to withstand remarkable mechanical stress due to system pressure and bolting.


A slip on flange is connected with pipes or fittings by two fillet welds, inside and outside the flange. The diameter of a slip on flange is larger than the diameter of the connected pipe so it can slide on the pipe to fit it smoothly.

Threaded Flanges, TH Flanges

Threaded flanges are joined to pipes by screwed connections, generally without welding activities (in certain cases, though, small welds are applied to increase the strenght of the connection).

Socket Welding Flanges, SW Flange

Socket weld flanges are connected to pipes using a fillet weld which is executed on the outer of the flange. Socket Weld Flanges are used for small-size and high-pressure piping. Their static strength is equal to slip on flanges, but their fatigue strength is stronger than double-welded slip on flanges.

Lap Joint Flanges

Lap joint flanges do not have a raised face and are used in conjunction with stub ends . Lap joint flanges are similar to slip on flanges except for the radius at the crossing of the flange face and the bore to accommodate the flanged portion of the stub end.

Price and mechanical properties are higher than ordinary casting flange a grade. The flange is a part that connects the pipe with the pipe and the valve, is connected to the pipe end. It is also used for the flange on the equipment inlet and outlet.

Standard we supply
Slip-On Flanges, SO Flange
Common flange types
Anchor flange
Specialty flange
150LB Carbon steel forged flange
Material Grades
Custom pipe flanges can be manufactured from a wide variety of materials and material grades.

About Sunny Steel

Our team are highly trained and experienced in servicing and producing all types of steel supplies. Whether you've got a large construction project, or need parts for industrial machinery, our team of steel fabrication consultants will ensure that your project is provided with the parts you need, when you need them.

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