The Lined Pipe Insert (LP) spring check valve is designed to mate between two flanges on most lined pipe systems. It provides the simplest most economical way to install a check valve in a lined piping system. No gaskets are required; just spread the flanges, center the valve and bolt the flanges together. LP valves are available in fluoropolymer (PTFE/FEP/PFA) and Alloy C-276 to satisfy the most demanding applications. The standard spring material is Alloy C-276. Other materials are available upon request.