Bushing, Spigot x FPT (Flush Style) PVC Schedule 80 4" x 2" (838-420)

The 4" x 2" PVC Schedule 80 Flush Bushing (838-420) transitions a 4" solvent-welded socket connection down to a 2" female-threaded outlet in a single compact fitting — with a flush-style profile that seats recessed within the mating 4" socket rather than projecting outward from its face. The spigot end solvent-welds permanently into any standard 4" Schedule 80 slip socket upstream, while the 2" FPT outlet accepts any standard 2" male-threaded fitting, valve, nipple, or equipment connection downstream.

Compared to the adjacent 838-422 (4" x 3"), the 838-420 steps the outlet down an additional pipe size to 2" — a more pronounced size differential that positions this bushing for applications where the downstream threaded service connection carries meaningfully lower flow than the primary 4" header. The combination of a permanent, solvent-welded 4" spigot inlet and a removable 2" FPT outlet reflects the same core design logic as all 838-series flush bushings: the upstream joint is fixed and becomes part of the surrounding Schedule 80 assembly, while the downstream threaded port remains serviceable — allowing the 2" male-threaded valve, instrument, strainer, chemical injection assembly, or equipment connection at the outlet to be removed and replaced without disturbing the permanent 4" solvent-welded joint upstream.

The more significant size differential between the 4" inlet and 2" outlet makes the 838-420 particularly well suited to systems where the downstream threaded connection serves a dedicated service function rather than a continuation of the primary distribution run — a 2" isolation valve on a chemical process branch, a 2" pump suction or discharge port fed from a 4" header, an equipment inlet where a 2" threaded port must interface with a 4" solvent-welded Schedule 80 system, or a strainer or filter assembly where the 2" threaded connection is specified against a larger upstream run. The single-fitting transition eliminates the need for a secondary reducer or adapter between the 4" slip socket and the 2" threaded outlet, keeping the assembly compact and the joint count low at the transition point.

The flush-style profile seats fully recessed within the 4" socket — avoiding the protruding hex head that would create clearance interference in tight mechanical spaces, close-coupled valve assemblies, and equipment rooms where adjacent piping or structural elements limit working clearance at the fitting. This profile advantage is particularly relevant at the 4" to 2" size differential, where a hex bushing would protrude substantially from the socket face and create a more pronounced obstruction than at smaller size differentials.

Manufactured to Schedule 80 specifications and dimensionally compliant with ASTM D2467, the 838-420 delivers the elevated wall thickness and pressure rating that Schedule 80 gray PVC is specified for in chemical processing, industrial fluid handling, and demanding commercial applications. Gray PVC construction provides broad chemical compatibility with acids, alkalis, and industrial process fluids. NSF 61 certification confirms suitability for potable water contact where required.

Specifications:

Industries & Applications:

• Chemical Processing — permanent-inlet, serviceable-outlet reducing transitions at 2" valve bodies, chemical injection assemblies, and equipment ports in 4" process fluid and chemical distribution systems where the upstream joint is fixed but the 2" downstream connection must remain removable for maintenance
• Industrial Process Piping — reducing transitions from 4" solvent-welded Schedule 80 headers to 2" threaded valve, pump, instrument, or equipment connections in plant utility and process fluid systems where a moderate-to-significant size step-down is engineered into the system
• Water & Wastewater Treatment — reducing transitions in treatment plant process piping where a permanent 4" slip-welded inlet feeds a serviceable 2" threaded equipment or valve connection at a service branch or instrument tap point
• Commercial & Industrial Plumbing — tight-clearance reducing bushings at valve isolation points and equipment connections in high-pressure mechanical systems where a 4" slip inlet must transition to a 2" threaded service connection in a single fitting
• Aquaculture & Food Processing — corrosion-resistant reducing transitions at 2" equipment and valve connections in recirculating systems and chemical-exposure fluid handling installations where the upstream 4" joint is permanent and the downstream 2" connection requires periodic service
• Irrigation & Agriculture — 4" solvent-welded mainline-to-2" threaded valve or equipment transitions in high-pressure chemical injection and large-scale irrigation distribution systems where the downstream connection serves a dedicated service or injection function