Union (O-Ring Type), FPT x FPT PVC Schedule 80 1/2" (898-005)

This 1/2" Schedule 80 PVC O-Ring Union provides a removable, pressure-tight connection in threaded PVC piping systems, allowing sections of pipe, valves, or equipment to be disconnected and reassembled without cutting into the line. Both tail piece ends are female NPT threaded, accepting 1/2" male-threaded pipe, nipples, or fittings on each side of the union joint.

The three-piece construction — two FPT tail pieces and a threaded union nut — is the defining advantage of a union fitting. Once both tail pieces are made up to the adjoining threaded components, the union nut draws the two faces together, compressing the O-ring to form a leak-free seal. When maintenance, inspection, or component replacement is required, the nut is backed off and the joint separates cleanly without disturbing the rest of the system. This makes the 898-005 an essential fitting anywhere future serviceability is a design requirement.

The O-ring seal at the union face is a critical differentiator from flat-face or thread-seal union designs. The elastomeric O-ring conforms precisely to both mating faces, providing a reliable, repeatable seal through multiple disassembly and reassembly cycles — an important characteristic in systems subject to regular maintenance intervals or seasonal shutdowns.

Manufactured in dark gray Schedule 80 PVC, this union delivers greater wall thickness and mechanical strength than Schedule 40 equivalents, suited for industrial, chemical processing, and commercial installations operating at elevated pressures or requiring enhanced impact resistance. PVC's broad chemical resistance profile covers acids, bases, salts, chlorine, and most common process fluids. NSF/ANSI 61 listing confirms suitability for potable water contact.

Apply PTFE tape or compatible thread sealant to all male threads engaging the FPT tail pieces. Hand-tighten plus one to two turns — avoid over-torquing PVC female threads. The union nut should be tightened firmly by hand; use a strap wrench if needed, but do not apply excessive mechanical force to the nut. Inspect the O-ring for cuts, deformation, or chemical degradation during each disassembly; replace before reassembly if any wear is visible. Apply published pressure derating factors for service temperatures above 73°F.

Specifications:

Industries & Applications:

• Industrial Process Piping — Installed adjacent to pumps, valves, flow meters, and chemical injection points where components must be periodically removed for inspection, cleaning, or replacement without cutting the line
• Water & Wastewater Treatment — Provides removable joints at chemical dosing equipment, sampling ports, pressure gauges, and instrumentation connections in treatment plant process piping
• Commercial Plumbing — Used in mechanical rooms and utility chases to create serviceable break points in PVC threaded piping at water heaters, backflow preventers, and shutoff valve assemblies
• Chemical Handling & Laboratory Systems — Enables disconnection of piping at chemical storage tanks, reactors, and process equipment in environments where corrosion resistance and clean disassembly are both required
• Irrigation & Agricultural Systems — Installs at filter housings, chemical injection assemblies, and pump connections on 1/2" branch lines where seasonal maintenance and winterization require routine disassembly
• Aquaculture & Pool/Spa Systems — Provides maintainable connections at chemical feed points, pump unions, and filtration equipment in recirculating water systems subject to frequent service access