LWN Flange

Designed for high-pressure and high-temperature applications, LWN flanges feature an extended tapered neck to reduce stress concentration and ensure leak-proof connections. Crafted from stainless steel, duplex, or alloy materials (ASME B16.5/EN 1092-1 compliant), they excel in critical industries like oil & gas, petrochemical, and power generation. With superior fatigue resistance and full penetration weld compatibility, our LWN flanges guarantee 20+ years of reliable service. Custom bore sizes, RTJ/grooved faces, and NACE MR0175 certifications available.

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Long Weld Neck Flange

Long Weld Neck Flange (LWN) is an extended form of butt welded flange with a neck, whose neck height is significantly higher than that of ordinary butt welded flanges. The neck is usually designed in a straight cylindrical shape, and the height is adjusted according to the nominal diameter (DN): when DN ≤ 100, the neck height is 229mm, and when DN>100, it is 305mm. The thickness of the neck wall gradually transitions to the thickness of the pipe wall, effectively improving stress distribution, enhancing the stiffness and load-bearing capacity of the flange, and suitable for working conditions with high pressure, high temperature, and frequent temperature fluctuations.

SIZE:

DN10(3/8")	DN15(1/2")	DN20(3/4")	DN25(1")	DN40(1-1/2")
DN50(2")	DN80(3")	DN100(4")	DN125(5")	DN150(6")
DN200(8")	DN250(10")	DN300(12")	DN350(14")	DN400(16")
DN450(18")	DN500(20")	DN550(22")	DN600(24")