A weld neck is a type of pipe fitting commonly used in industrial applications. It features a long tapered neck that allows for a smooth transition between the pipe and the fitting. This design helps to reduce stress concentrations and provides a strong, reliable connection when welded to a pipe. Weld neck fittings are often made from materials like carbon steel, stainless steel, or alloy steel, making them suitable for high-pressure and high-temperature environments. They are typically used in systems involving oil, gas, or chemical processing, where durability and integrity are crucial for safety and performance.