Reducer Coupling, Slip x Slip PVC Schedule 40 4" x 3" (429-422)
$19.65
The 429-422 is a 4" x 3" PVC Schedule 40 reducer coupling in a slip x slip (socket x socket) configuration. The 4" socket end accepts plain-end pipe for solvent welding on the inlet side, while the 3" socket end does the same on the outlet — delivering a permanent, one-step size reduction in a single fitting without the need for bushings, adapters, or intermediate components.
The 4" x 3" combination is one of the most practical one-step reductions in the Schedule 40 catalog. The two sizes are closely matched in flow capacity, which keeps velocity change across the reduction gradual and minimizes turbulence and pressure drop at the transition point. This makes the 429-422 well suited not only for straight size reductions in distribution piping, but also for system designs where maintaining flow efficiency through the transition is an engineering consideration.
Manufactured from virgin PVC compound to Schedule 40 dimensional standards, the 429-422 delivers solid pressure ratings for standard commercial and light industrial service. The all-slip design creates a fully solvent-welded, permanent joint on both ends — with no threads to corrode, back out, or leak under pressure cycling or thermal expansion.
Like all Schedule 40 PVC fittings, the 429-422 is lightweight, corrosion-proof, and resistant to biological fouling and a broad range of chemicals encountered in plumbing, irrigation, and process applications.
Specifications:
| Attribute | Detail |
|---|---|
| Part Number | 429-422 |
| Material | PVC (Polyvinyl Chloride) |
| Schedule / Pressure Class | Schedule 40 |
| End Connections | Slip (Socket) x Slip (Socket) |
| Fitting Type | Reducer Coupling |
| Inlet Size | 4" |
| Outlet Size | 3" |
| Color | White |
| Applicable Standard | ASTM D2466 |
| NSF Listed | NSF 61 (potable water) |
| Temperature Range | Up to 140°F (60°C) at rated pressure |
| Manufacturer | Spears Manufacturing |
Industries & Applications:
- Municipal Water & Wastewater — Reducing a 4" distribution or collection main to a 3" branch or service run in a single solvent-weld fitting
- Irrigation Systems — Stepping down a 4" mainline to a 3" zone header or lateral distribution line in commercial or agricultural irrigation infrastructure
- Industrial Process Piping — Transitioning between pipe sizes in process fluid distribution systems where a permanent, low-turbulence reduction is required
- Commercial Plumbing — Reducing supply or drain piping from 4" to 3" in commercial construction where a compact, single-fitting transition is preferred
- Water Treatment — Connecting mismatched pipe sizes across process equipment, pump outlets, and distribution headers in treatment plant piping
- Agriculture — Stepping down large-bore PVC mainlines to smaller distribution headers feeding multiple irrigation zones or equipment manifolds
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Reducer Coupling, Slip x Slip PVC Schedule 40 4" x 3" (429-422)
The 429-422 is a 4" x 3" PVC Schedule 40 reducer coupling in a slip x slip (socket x socket) configuration. The 4" socket end accepts plain-end pipe for solvent welding on the inlet side, while the 3" socket end does the same on the outlet — delivering a permanent, one-step size reduction in a single fitting without the need for bushings, adapters, or intermediate components.
The 4" x 3" combination is one of the most practical one-step reductions in the Schedule 40 catalog. The two sizes are closely matched in flow capacity, which keeps velocity change across the reduction gradual and minimizes turbulence and pressure drop at the transition point. This makes the 429-422 well suited not only for straight size reductions in distribution piping, but also for system designs where maintaining flow efficiency through the transition is an engineering consideration.
Manufactured from virgin PVC compound to Schedule 40 dimensional standards, the 429-422 delivers solid pressure ratings for standard commercial and light industrial service. The all-slip design creates a fully solvent-welded, permanent joint on both ends — with no threads to corrode, back out, or leak under pressure cycling or thermal expansion.
Like all Schedule 40 PVC fittings, the 429-422 is lightweight, corrosion-proof, and resistant to biological fouling and a broad range of chemicals encountered in plumbing, irrigation, and process applications.
Specifications:
| Attribute | Detail |
|---|---|
| Part Number | 429-422 |
| Material | PVC (Polyvinyl Chloride) |
| Schedule / Pressure Class | Schedule 40 |
| End Connections | Slip (Socket) x Slip (Socket) |
| Fitting Type | Reducer Coupling |
| Inlet Size | 4" |
| Outlet Size | 3" |
| Color | White |
| Applicable Standard | ASTM D2466 |
| NSF Listed | NSF 61 (potable water) |
| Temperature Range | Up to 140°F (60°C) at rated pressure |
| Manufacturer | Spears Manufacturing |
Industries & Applications:
- Municipal Water & Wastewater — Reducing a 4" distribution or collection main to a 3" branch or service run in a single solvent-weld fitting
- Irrigation Systems — Stepping down a 4" mainline to a 3" zone header or lateral distribution line in commercial or agricultural irrigation infrastructure
- Industrial Process Piping — Transitioning between pipe sizes in process fluid distribution systems where a permanent, low-turbulence reduction is required
- Commercial Plumbing — Reducing supply or drain piping from 4" to 3" in commercial construction where a compact, single-fitting transition is preferred
- Water Treatment — Connecting mismatched pipe sizes across process equipment, pump outlets, and distribution headers in treatment plant piping
- Agriculture — Stepping down large-bore PVC mainlines to smaller distribution headers feeding multiple irrigation zones or equipment manifolds
- Part #:
- 429-422
- Product Family:
- Sch 40 PVC
- Carton Qty:
- 4
- Pallet Qty:
- 400
- Size:
- 4'
