Lap Joint Flange

A Lap Joint Flange is a two-part flange that consists of a loose flange and a stub end, where the flange slips over the pipe and rests against the back of the stub end. This design allows the flange to rotate freely, making alignment easier. Lap Joint Flanges are commonly used in low-pressure applications that require frequent dismantling for maintenance or inspection, as they offer flexibility and ease of installation in various pipeline configurations.

Lap Joint Flanges are used in low-pressure and non-critical applications, where pipe connections need to be dismantled frequently for maintenance or inspection. Commonly used in the oil and gas, water treatment, chemical processing, and food and beverage industries, they are also ideal for situations requiring the use of expensive alloys since the flange itself doesn’t need to be made from the same material as the pipe, reducing costs.

Manufacturers offer Lap Joint Flanges in a variety of materials, including carbon steel, stainless steel, alloy steel, and specialty metals like nickel alloys. The flange can be made from lower-cost materials, while the stub end, which is welded to the pipe, matches the pipe’s material. This flexibility in material choice helps reduce costs in applications involving high-grade or corrosion-resistant materials.

Lap Joint Flanges offer several advantages, including easy alignment during installation, cost savings in cases of expensive piping material, and flexibility in applications requiring frequent disassembly. Because they’re not permanently attached, these flanges allow for quick and simple maintenance and alignment adjustments. They are also cost-effective for systems that require flanges made from costly materials, as only the stub end needs to be made from the same material as the pipe.

Lap Joint Flanges are available in various pressure classes, typically ranging from Class 150 to Class 1500, but the most common ratings are in the lower to moderate ranges, such as Class 150 and Class 300. These ratings indicate the flange’s ability to withstand specific pressure levels at certain temperatures. Lap Joint Flanges are primarily used in low-pressure systems, making them suitable for applications that do not require high-pressure handling.