150LB FF PE Flange

The 150LB FF PE Flange is a flat face, plain end flange engineered for low-to-medium pressure piping systems where a full, unraised sealing surface is required. Manufactured to ASME B16.5, this 150-pound class flange delivers reliable, leak-free connections in pipelines handling water, process fluids, and utility services. The flat face (FF) configuration ensures uniform gasket compression across the entire flange face, making it the preferred choice when connecting to flanged equipment with non-metallic or brittle counterpart flanges — such as cast iron valves, pumps, and plastic-lined components — where a raised face could cause cracking or uneven loading.

Conforming to ASME B16.5, this plain end (PE) flange is available across an extensive dimensional range, with outside diameters spanning from 0.44 inches through to 65 inches, covering virtually every pipeline size encountered in industrial and commercial installations. The 150LB pressure class is the most widely used rating in building services and general process piping, typically rated for non-shock service at up to 285 PSI (19.6 bar) for carbon steel at ambient temperature, with ratings derated at elevated temperatures per ASME pressure-temperature tables. The plain end preparation allows field welding or mechanical attachment to match the host pipe specification, offering flexibility across different pipe schedules and materials.

This 150LB flat face PE flange is well suited to water treatment plants, municipal water distribution, HVAC chilled and heating water systems, fire protection pipework, chemical processing lines, and general industrial fluid handling. The flat face design is especially important in systems where cast iron or ductile iron flanged equipment is present, as ASME and industry guidelines recommend full-face gaskets and flat face flanges in these assemblies to prevent bolt-load-induced fracture. It is equally applicable in low-pressure compressed air distribution, cooling water circuits, and slurry or wastewater pipelines where full-face sealing minimises the risk of gasket blowout.

As a 150LB class flange per ASME B16.50, this component is dimensionally interchangeable with ASME B16.5 Class 150 flanges in the same pressure class, providing broad compatibility with existing plant pipework and standard bolt patterns. The plain end configuration is compatible with butt-weld, socket-weld, or slip-on attachment depending on the specific flange type ordered, and the flat face finish is suitable for use with full-face rubber, EPDM, PTFE, or compressed fibre gaskets. Buyers specifying flanges for mixed-material piping systems or upgrading legacy cast iron infrastructure will find this flange a direct, standards-compliant replacement for older flat face fittings.