Class 150 Forged Carbon Steel Lap Joint, Flat-Face Flange
Class 150 ASTM A105 / ASME SA-105 Lap Joint Flange
The Class 150 ASTM A105 / ASME SA-105 Forged Carbon Steel Lap Joint Flat-Face Flange provides a versatile, serviceable connection for industrial piping systems requiring convenient alignment, assembly, and disassembly. Designed for use with a compatible lap joint stub end, this carbon steel flange is commonly selected for piping systems requiring frequent inspection, maintenance, or component replacement.
ASTM A105 / ASME SA-105 Forged Carbon Steel
Manufactured from ASTM A105 / ASME SA-105 forged carbon steel, this lap joint flange provides excellent strength, toughness, and durability. A105/SA-105 carbon steel is widely specified for forged steel flanges, fittings, valves, and pressure-containing piping components used throughout industrial facilities.
The Class 150 designation identifies the ASME pressure class rather than a maximum operating pressure of 150 PSI. Allowable pressure depends on material, operating temperature, and applicable pressure-temperature ratings.
Lap Joint Flange Design
Unlike a weld neck or slip on flange, a lap joint flange is not welded directly to the pipe. Instead, it fits loosely behind a compatible stub end that is attached to the piping. This arrangement allows the backing flange to rotate independently, helping simplify bolt-hole alignment during installation.
Lap joint construction can also make piping systems easier to dismantle for maintenance, inspection, or modification.
Flat-Face Flange Configuration
The flat-face lap joint flange provides the backing connection used with the stub end. The stub end itself supplies the gasket-contact sealing surface between mating assemblies.
Class 150 A105/SA-105 lap joint flanges are commonly manufactured to ASME B16.5 dimensional requirements for applicable sizes, including dimensions, bolt patterns, tolerances, and pressure-temperature ratings.
For pipe fabricators, industrial contractors, maintenance departments, and process facilities, the Class 150 A105/SA-105 forged carbon steel lap joint flange provides a durable and practical solution for piping systems where alignment flexibility, accessibility, and convenient disassembly are important.