Reducer Coupling, Slip x Slip PVC Schedule 40 3/4" x 1/2" (429-101)

This 3/4" x 1/2" Schedule 40 PVC Reducer Coupling (Slip x Slip) provides a straight-through inline size reduction from a 3/4" socket pipe run to a continuing 1/2" socket pipe run — accepting a 3/4" PVC pipe end at the larger inlet socket for a permanent solvent-cement bond and providing a 1/2" slip socket at the outlet for a permanent solvent-cement bond on the reduced-diameter downstream continuation. Constructed in white Schedule 40 PVC, it delivers the most common adjacent-size inline step-down in residential and light commercial all-socket PVC systems in the most compact possible single fitting body — without a direction change, without a fitting hub intermediate, and without introducing threaded connections into an all-socket assembly at the reduction point.

The 3/4" slip socket inlet accepts 3/4" PVC pipe for a permanent solvent-cement bond, anchoring the fitting to the upstream 3/4" socket distribution assembly at the inline reduction point. The 1/2" slip socket outlet accepts 1/2" PVC pipe for a permanent solvent-cement bond on the downstream reduced-diameter pipe run, completing the all-socket size transition in a single cemented coupling body that continues the pipe run in a straight line at the new 1/2" diameter. This is the correct choice when both the upstream 3/4" assembly and the downstream 1/2" continuation are all-socket cemented PVC pipe runs requiring an inline step-down without any direction change or fitting hub intermediate at the reduction point — distinct from the 406-101 (3/4" x 1/2" 90 Degree Reducing Slip Elbow, confirmed in this catalog session), which simultaneously reduces and redirects the run 90 degrees rather than continuing straight; from the 401-095 (3/4" x 3/4" x 1/2" Reducing Tee, confirmed in this catalog session), which taps a 1/2" branch perpendicular to a full-size 3/4" inline run rather than reducing the run itself; from the 437-130 (3/4" x 1/2" Spigot x Slip Reducer Bushing — noting 437 series entries confirmed at this combination include 837-101 at Schedule 80 Spigot x Slip), which cements into a socket fitting hub rather than joining two pipe run ends inline; and from the 430-101 (3/4" x 1/2" FPT Reducer Coupling, confirmed in this catalog session), which joins two male-threaded pipe ends rather than cementing to socket pipe runs. The 3/4" to 1/2" adjacent-size step-down at code 101 is the most universally confirmed size combination in this entire catalog session — appearing across thirteen separate fitting series — and 429-101 is the all-socket inline reducer coupling serving this step-down, most widely encountered in residential and light commercial irrigation systems where a 3/4" socket mainline or sub-main must transition inline to a 1/2" socket lateral supply run without a direction change; in drip system distribution assemblies where a 3/4" header must reduce inline to a 1/2" drip emitter supply run at the start of a lateral zone; and in commercial plumbing distribution assemblies where a 3/4" socket branch supply main must reduce inline to a 1/2" dedicated fixture or equipment service run.

Rated to approximately 480 psi at 73°F (governed by the 3/4" slip inlet), this coupling is suited for standard commercial and light industrial pressure service. Its PVC composition 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.

Apply solvent cement to both the pipe end and fitting socket at each port per ASTM D2564 procedures, using a primer appropriate for the pipe and fitting schedule. Insert pipe fully into each socket and maintain a quarter-turn during assembly for even cement distribution. Note that the inlet (3/4") and outlet (1/2") are different diameters — confirm pipe diameters before cementing each joint to avoid inserting the incorrect pipe size into either port. Allow adequate cure time before pressurizing, and derate pressure ratings for elevated temperatures per published derating curves.

Specifications:

Industries & Applications:

• Irrigation & Water Distribution — Provides a straight-through inline 3/4" to 1/2" socket size reduction at mainline-to-lateral transition points, sub-main-to-distribution-run transitions, and zone supply step-down points in residential and light commercial irrigation systems where a 3/4" socket pipe run must reduce inline to a 1/2" socket lateral supply run without a direction change — the most common all-socket inline size reduction at the dominant residential irrigation system transition diameter
• Drip & Micro-Irrigation Systems — Transitions 3/4" socket distribution headers inline to 1/2" socket drip emitter supply laterals, micro-irrigation zone supply runs, and small-bore distribution continuations at the start of each drip lateral in residential and light commercial drip systems where the 3/4" all-socket header must step down to 1/2" at the lateral origin point in a straight line without a direction change or fitting hub intermediate
• Commercial Plumbing — Provides a straight-through inline 3/4" to 1/2" socket size reduction at branch supply step-down points, dedicated service line transition points, and equipment feed approach pipe run reductions in commercial building water distribution systems where a 3/4" socket branch supply main must reduce inline to a 1/2" dedicated fixture or equipment service run without a direction change
• Fire Suppression Systems — Transitions 3/4" socket branch line pipe runs inline to 1/2" socket sprinkler head drops and lateral continuation runs in light-hazard and residential Schedule 40 PVC fire suppression grid assemblies where the inline step-down from 3/4" to 1/2" must occur without a direction change at the reduction point throughout the all-cemented grid
• Industrial Process Piping — Provides a straight-through inline 3/4" to 1/2" socket pipe run size reduction at distribution header step-down points, service branch transition points, and instrument supply run transition points in water treatment, chemical processing, and manufacturing facilities where the 3/4" socket distribution run must reduce inline to a 1/2" socket service or instrument supply continuation
• Water Treatment & Aquaculture — Used at inline step-down points along 3/4" all-socket distribution runs where the 1/2" socket continuation must originate in a straight line without a direction change, with NSF/ANSI 61 compliance required throughout the all-cemented assembly at each 3/4" to 1/2" inline transition point