Cap, FPT PVC Schedule 80 3/8" (848-003)

This 3/8" Schedule 80 PVC Threaded Cap (FPT) provides a clean, pressure-rated closure for any standard 3/8" male NPT-threaded pipe end, nipple, or fitting outlet in industrial, chemical, and commercial piping systems. Constructed in dark gray Schedule 80 PVC, it delivers the elevated wall thickness and pressure capacity required in demanding installations where standard Schedule 40 fittings are insufficient and where a reliable, corrosion-resistant terminal closure is needed.

The single female pipe thread (FPT) interior is cut to NPT tapered thread standards, threading directly onto any 3/8" male NPT pipe end or nipple to form a pressure-tight mechanical closure when made up with thread sealant or PTFE tape. As a terminal fitting, the threaded cap is the standard solution for permanently or temporarily closing unused branch outlets, capping system test points between pressure tests, sealing spare ports on manifolds and valve bodies, and terminating dead-end lines during phased system construction or expansion.

Rated to 920 psi at 73°F, this cap is well-suited for demanding pressure service across a broad range of fluid handling applications. Its PVC composition provides excellent resistance to acids, bases, salts, and chlorinated water, making it a durable long-term closure in corrosive environments where metal caps would degrade or seize onto threads over time. NSF/ANSI 61 listing confirms suitability for potable water contact, including use in drinking water distribution and treatment systems.

Install using a quality pipe thread sealant or PTFE tape on the male NPT threads before engagement. Avoid over-torquing — PVC threads require hand-tight plus one to two turns; excessive force can crack the fitting or distort the thread engagement. If used as a temporary test cap, inspect the fitting and threads before returning to service. Derate pressure ratings for elevated temperatures per published derating curves.

Specifications:

Industries & Applications:

• Industrial Process Piping — Closes unused branch outlets, spare manifold ports, and dead-end test points on chemical processing, water treatment, and manufacturing piping systems during construction, expansion, or pressure testing phases
• Commercial Plumbing — Caps 3/8" male NPT pipe ends and nipple stubs on pressurized supply systems, fixture rough-ins, and valve assemblies awaiting final connections or future branch extensions
• Irrigation & Water Distribution — Seals unused threaded outlets on manifold bodies, filter housings, and zone headers in agricultural and municipal irrigation systems, allowing future tap additions without cutting into the main line
• Chemical Handling — Provides a corrosion-resistant threaded closure on systems conveying acids, caustics, fertilizer solutions, and other fluids incompatible with metal caps, which may corrode, seize, or contaminate the system
• Water Treatment & Aquaculture — Used to seal spare instrument ports, sampling taps, and unused filter housing connections in recirculating and treatment systems where NSF/ANSI 61 compliance and chemical resistance are required
• HVAC & Mechanical Systems — Caps unused threaded ports on cooling tower headers, chilled water distribution manifolds, and chemically treated water systems requiring Schedule 80 pressure ratings at small-diameter instrument or drain connections