Union (O-Ring Type), FPT x FPT PVC Schedule 40 1/2" (498-005)

This 1/2" Schedule 40 PVC Threaded Union (O-Ring Type, FPT x FPT) provides an all-threaded PVC piping system with a serviceable, pressure-rated disconnect point that can be broken and remade without cutting pipe, removing nipples, or disturbing adjacent threaded fittings. Constructed in white Schedule 40 PVC with an EPDM or Buna-N O-ring seal, it is an essential component in threaded PVC systems anywhere a pump, filter, valve, chemical feeder, or other inline equipment must be periodically removed, inspected, or replaced without dismantling the surrounding pipe run.

The union consists of three parts: two FPT body halves that thread directly onto opposing male NPT pipe ends or nipples, and a threaded union nut that draws the two halves together and compresses the O-ring to create a leak-free pressure seal at the joint face. The all-threaded configuration makes this union the correct choice for systems built entirely from threaded PVC components — where solvent-cement joints are absent or not preferred — providing the same serviceable disconnect functionality as the slip union series without requiring any cemented joints at the union itself. Both FPT ends accept any standard 1/2" male NPT pipe end, nipple, or fitting for a pressure-tight mechanical connection when made up with thread sealant or PTFE tape.

Rated to 850 psi at 73°F, this union delivers reliable pressure performance across the full range of standard commercial and light industrial water distribution service. Its PVC and O-ring construction provides excellent resistance to corrosion, scale, chlorinated water, and a broad range of chemical exposures. NSF/ANSI 61 listing confirms suitability for potable water contact, including use in drinking water distribution and treatment systems.

To assemble: apply thread sealant or PTFE tape to the male NPT threads on each pipe end or nipple, then thread each FPT body half onto its respective pipe end and tighten appropriately — hand-tight plus one to two turns; avoid over-torquing PVC threads. Seat the O-ring into the body groove, bring the two halves together, and hand-tighten the union nut — do not use tools to over-tighten, as the O-ring provides the face seal and excessive torque on the nut is unnecessary and may damage the threads. To service or disconnect, simply hand-loosen the union nut and separate the body halves; the threaded ends remain on their respective pipe ends and can be re-engaged after service without disturbing the surrounding system. Derate pressure ratings for elevated temperatures per published derating curves.

Specifications:

Industries & Applications:

• Industrial Process Piping — Provides serviceable disconnect points at chemical metering pumps, inline filters, flow meters, solenoid valves, and instrumentation sections in fully threaded Schedule 40 PVC systems across water treatment, chemical processing, and manufacturing facilities
• Commercial Plumbing — Installed at pump inlets and outlets, pressure tanks, water softeners, and water treatment equipment in threaded PVC supply systems to allow removal and service without cutting pipe or breaking adjacent threaded connections
• Irrigation & Water Distribution — Used at pump stations, filter housings, backflow preventers, and zone control valve assemblies in threaded PVC irrigation systems where seasonal or periodic equipment removal is required and solvent-cement joints are not present at the union location
• Chemical Handling — Provides a corrosion-resistant, re-engageable threaded disconnect in systems conveying acids, caustics, fertilizer solutions, and other fluids incompatible with metal union fittings, particularly in fully threaded PVC chemical feed and metering assemblies
• Water Treatment & Aquaculture — Installed at UV sterilizers, media filters, chemical dosing pump connections, and recirculating system components in threaded PVC assemblies where routine maintenance access is essential and the all-threaded configuration is preferred over solvent-cement unions
• HVAC & Mechanical Systems — Used at inline components on threaded PVC sections of chilled water loops, cooling tower pump connections, and chemically treated water systems where equipment isolation and serviceability are required at 1/2" threaded service connections