Visually, a welding neck flange features an elongated tapered neck that gradually transitions to match the wall thickness of the connected pipe. This unique design allows the weld joint to extend from the flange's end face to the pipe's outer wall, forming a high-strength welded zone. This structure makes welding neck flanges particularly suitable for high-pressure, high-temperature, or environments with severe temperature fluctuations.
Key Characteristics
High Connection Strength
Due to the extensive weld area and groove butt welding, the connection between the welding neck flange and the pipe exhibits exceptional strength, effectively resisting internal pressure and external bending stresses.
This welding method virtually fuses the pipe and flange into a single integrated unit.
Superior sealing performance
The sealing surface of the welding neck flange is perpendicular to the pipe axis, ensuring even compression of the gasket under bolt preload.
This design achieves excellent sealing performance, effectively preventing leakage of media within the pipeline.
Adaptability to Harsh Conditions
Compared to other flange types (e.g., slip-on flanges), welding neck flanges better withstand demanding operating conditions.
They can tolerate higher pressures and temperatures, and their stress distribution during thermal expansion/contraction of pipes is more rational, reducing risks of leakage or structural failure.
As a result, they are the preferred choice for critical pipelines in industries such as oil, chemical, power, and natural gas.
Precision installation requirements
Installation of welding neck flanges requires professional welding techniques and non-destructive testing (NDT) to ensure weld quality.
The welding process must guarantee full penetration and defect-free joints; otherwise, it may pose safety hazards.
This type of flange demands higher technical proficiency from operators and stricter quality control procedures.
Specification
Size :NPS from 1/2'' to 24'', CLASS from 150 to 2500
Standard :ANSI/ASME B 16.5, DIN, JIS, AWWA, API, ISO etc.
Grade:CLASS150,CLASS300,CLASS400,CLASS600, CLASS900, CLASS1500, CLASS2500
Carbon Steel-ASTM A105,ASTM A350 LF1,LF2,LF3,A36,ASTM A234 WPB
GNEE
Welded neck flange for sale
