Reducer Bushing, Spigot x FPT PVC Schedule 40 1/2" x 1/8" (438-071)

This 1/2" x 1/8" Schedule 40 PVC Reducer Bushing (Spigot x FPT) provides a compact mixed-connection transition from a 1/2" socket fitting hub down to a 1/8" female NPT-threaded micro-bore outlet, consolidating an extreme 4:1 diameter reduction and a socket-to-thread material transition into a single fitting body — serving the most specialized application in the confirmed 438 series catalog: incorporating a bleed valve, vent connection, test point stub, or ultra-small-bore instrument fitting directly at a 1/2" socket fitting hub in all-socket cemented PVC assemblies where no intermediate adapter assembly is practical. Constructed in white Schedule 40 PVC, it is the most compact and specialized confirmed Spigot x FPT reducer bushing entry in the 438 series at the smallest confirmed spigot inlet size.

The 1/2" spigot (male plain end) is sized to insert directly into the hub of any standard 1/2" socket-end fitting — tee branch outlet, cross port, coupling end, elbow outlet, or valve body — and is solvent-cemented in place to form a permanent, leak-free joint at the outer face of the hub. The 1/8" FPT interior accepts any standard 1/8" male NPT-threaded instrument fitting, bleed valve, vent plug, test point nipple, or micro-bore service component for a pressure-tight mechanical connection when made up with thread sealant or PTFE tape. The 1/8" FPT is the smallest standard NPT thread size in common commercial use — serving exclusively as a bleed port, vent connection, test point, or micro-bore instrument tap rather than a flow service branch; no meaningful flow service function is performed by a 1/8" branch from a 1/2" socket hub, and this fitting should be selected specifically when a permanent micro-bore access point must be built into a 1/2" socket fitting hub location. This entry is distinct from the adjacent 438-073 (1/2" x 3/8" Spigot x FPT, confirmed in this session), which serves slightly larger legacy instrument and service component connections at the 3/8" NPT outlet; from any 437 series all-slip counterpart at this size (Spigot x Slip, 1/2" x 1/8" if stocked), which provides a 1/8" socket outlet for a cemented pipe run; and from the 402-071 (1/2" x 1/2" x 1/8" Slip x Slip x FPT Tee, confirmed in this session), which provides a 1/8" FPT branch at an inline tee junction rather than at a socket fitting hub port. The 438-071 bushing is the correct fitting when the 1/8" micro-bore port must originate at an existing 1/2" socket fitting hub rather than at a full inline tee junction point.

Rated to approximately 600 psi at 73°F (governed by the 1/2" spigot end), this bushing carries the highest pressure rating of any confirmed 438 series entry — reflecting the elevated pressure capacity of Schedule 40 PVC at 1/2" nominal size. NSF/ANSI 61 listing confirms suitability for potable water contact.

Apply solvent cement to the spigot exterior and the interior of the receiving 1/2" socket hub per ASTM D2564 procedures, inserting fully and holding briefly for initial set. On the 1/8" FPT end, use PTFE tape — wrapping a minimum of two to three times in the thread direction — and confirm that the 1/8" male NPT threads of the mating component are started by hand and seated squarely before applying any additional torque; at 1/8", the thread engagement depth is the shallowest of any standard NPT size, making cross-threading a particularly common installation error that may crack the female thread interior without being immediately apparent under hand pressure. Avoid over-torquing — PVC threads require hand-tight plus approximately one turn at 1/8"; the margin between proper engagement and overtorque is extremely narrow at this size. Allow adequate cure time on the cemented spigot joint before pressurizing the system, and derate pressure ratings for elevated temperatures per published derating curves.

Specifications:

Industries & Applications:

• Industrial Process Piping — Incorporates 1/8" male-threaded bleed valves, vent fittings, test point nipples, and micro-bore instrument connections directly at 1/2" socket fitting hubs on small-bore process water distribution headers, chemical feed lines, and industrial fluid handling assemblies in water treatment, chemical processing, and manufacturing facilities where a micro-bore access point must be built into a 1/2" socket hub location without an intermediate adapter assembly
• Chemical Process Piping — Provides a corrosion-resistant micro-bore socket-to-thread transition at 1/2" socket fitting hub ports in systems conveying acids, caustics, fertilizer solutions, and other chemically aggressive fluids where 1/8" male-threaded bleed valves, vent connections, and micro-bore service stubs must be incorporated at 1/2" socket assembly hub locations without metal adapter chains
• Irrigation & Water Distribution — Provides 1/8" male-threaded bleed valve connections, test point stubs, and micro-bore vent fittings directly at 1/2" socket fitting hub ports in agricultural and residential irrigation pump station assemblies and distribution assemblies where a micro-bore access point must be incorporated at a 1/2" socket hub location
• Laboratory & Analytical Systems — Provides a 1/8" female-threaded micro-bore port at 1/2" socket fitting hub locations in laboratory, analytical, and pilot plant fluid distribution systems where bleed valves, vent fittings, sampling micro-valves, and micro-bore instrument connections at the smallest standard NPT size must be incorporated at 1/2" socket assembly hub locations
• Water Treatment & Aquaculture — Used at 1/2" socket fitting hub ports where 1/8" male-threaded bleed valves, micro-bore vent connections, and test point stubs must be incorporated directly at socket fitting hub locations with NSF/ANSI 61 compliance required throughout the assembly
• Commercial Plumbing — Provides a 1/8" male-threaded micro-bore test point, bleed valve stub, or vent connection at 1/2" socket fitting hub outlets in commercial building water distribution systems where micro-bore access must be incorporated at socket fitting hub locations without an intermediate multi-piece adapter assembly at the hub port