STEEL FLANGE ALLOY STEEL WELD NECK FLANGE ASTM A182 GR F11 CL1 F22 CL3 B16.5

STEEL FLANGE ALLOY STEEL WELD NECK FLANGE ASTM A182 GR F11 CL1 F22 CL3 B16.5

YUHONG GROUP deal with stainless steel seamless pipe and tube already more than 33 years, every year sell more than 80000 tons of stainless steel seamless pipe and tube. Our client already cover more than 65 countries. Our stainless steel seamless pipe and tube was width used in Mining, Energy, Petrochemical, Chemical Industry, Food plant, Paper plant, Gas and Fluid Industry etc.

Grades (F11 & F22): These are two common chrome-moly (chromium-molybdenum) alloy steel grades.

F11 (1.25Cr-0.5Mo): The standard, lower-cost grade for moderate high-temperature service like boiler and steam piping .

F22 (2.25Cr-1Mo): A "workhorse" grade with higher chromium and molybdenum content, providing superior creep strength and hydrogen attack resistance for more severe service .

Classes (CL1 & CL3): These denote different minimum mechanical strength requirements. Class 1 (CL1) has lower minimum tensile and yield strength, while Class 3 (CL3) has higher strength properties, making it the standard for most piping applications .

Weld neck flanges made from these alloy steels offer significant advantages in demanding environments:

Superior Strength and Stress Distribution: The tapered hub reinforces the connection and smoothly transfers stress from the flange to the pipe wall, preventing stress concentration. This makes it ideal for high-pressure and high-temperature applications, as well as for piping subject to vibration or thermal cycling .

Excellent High-Temperature Performance: The chromium and molybdenum in F11 and F22 provide high creep strength (resistance to deformation under sustained stress at high heat) and retain strength at elevated temperatures .

Enhanced Safety and Reliability: The butt-weld connection is a full-penetration weld, which is stronger and more reliable than the fillet welds used on slip-on flanges. This weld can be fully radiographed (X-rayed) for non-destructive examination (NDE), which is crucial for critical services .

Resistance to Hydrogen Attack: F22 grade is specifically advantageous in refinery service (like hydrotreaters) because it resists high-temperature hydrogen attack (HTHA), where hydrogen at high pressures and temperatures can cause internal decarburization and cracking in steel .

Smooth Flow and Reduced Erosion: The flange bore is machined to match the pipe's inner diameter, eliminating restrictions and turbulence at the joint, which reduces erosion and pressure drop .

Product Range:

WNRF Flanges Size : 1/8" NB TO 48"NB.

WNRF Flanges Class : 150#, 300#,400 #,600#,900#, 1500# & 2500 #.

Alloy Steel WNRF Flanges : ASTM A 182, GR F1, F11, F22, F5, F9, F91

Mechanical Properties of ASTM A182 Alloy Steel F11,F22 Flanges