ASTM A105 Forged Carbon Steel Lap Joint Flanges

The Lap Joint Flange (LJ Flange) is unique among flange types because it is always used in conjunction with a Stub End (a lap joint pipe fitting that is butt-welded to the pipe). The LJ flange itself slides over the pipe and is free to rotate around the Stub End. This feature is the primary advantage, as it makes bolt hole alignment quick and easy, which is critical during fabrication or large-scale assembly where pipe fitting tolerances can stack up. The flange material carries no direct fluid contact and is manufactured to ASTM A105, which specifies Forged Carbon Steel suitable for pressure systems. These flanges are secured by ASTM A193 Grade B7 Stud Bolts and their complementary ASTM A194 Grade 2H Heavy Hex Nuts. This system is often utilized in piping that requires frequent dismantling for inspection or cleaning, like systems using non-ferrous piping (where the Stub End is a corrosion-resistant alloy, but the reusable flange is carbon steel). Zeron Fasteners offers these flanges across all standard pressure classes (e.g., 150# to 600#) and conforming to ASME B16.5 dimensional standards.

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