Flange Types
Lap Joint Flanges
Two-piece flanges for systems requiring easy alignment and disassembly.
Lap joint flanges are a two-piece assembly consisting of a stub end (which is welded to the pipe) and a loose backing flange that slides over the pipe. The backing flange is free to rotate, allowing easy bolt hole alignment during installation. This feature makes lap joint flanges particularly useful in systems that require frequent disassembly for inspection, cleaning, or maintenance.
A significant cost advantage of the lap joint design is that the backing flange does not contact the process fluid. In corrosive service, the stub end can be made from an expensive corrosion-resistant alloy while the backing flange is ordinary carbon steel. This can reduce material costs substantially compared to using solid alloy flanges throughout the system.
Lap joint flanges are widely used in lined piping systems (PTFE, glass, rubber linings), food and pharmaceutical plants requiring frequent sanitary cleaning, and offshore platforms where bolt hole alignment in tight spaces is challenging. Flanges.IO stocks lap joint flanges and matching stub ends in carbon steel, stainless steel, and alloy materials. Contact us for availability and pricing.
