NIBCO Fig No C5801, 1-1/2 in. ABS DWV Coupling Hub, Solvent Weld

A straightforward, reliable ABS coupling that does its job

A good DWV coupling shouldn’t be exciting—it should be consistent, dimensionally true, and easy to install. That’s exactly how this NIBCO ABS DWV coupling has behaved for me across a few small projects, including a quick kitchen drain repair and an RV vent recoupling. It’s an unassuming hub-by-hub fitting, but its consistency and clean solvent-weld performance make it the sort of piece I like to keep in the bin.

What it is and where it fits

This is a 1-1/2 in. ABS DWV solvent-weld coupling designed to join two sections of the same nominal pipe diameter in a straight run. Both ends are hubs, which means they slip over the outside diameter of pipe (or a spigot-ended fitting). The material is ABS formulated for DWV (drain, waste, and vent) systems—so think gravity drainage and vent lines, not pressurized water supply.

Key characteristics:

• ABS-DWV construction for chemical and corrosion resistance
• Smooth interior to reduce friction and buildup
• Solvent-weld joint for a permanent, monolithic connection
• Meets ASTM D2661 and D3311

If you’re replacing a section of 1-1/2 in. ABS drain under a sink or reconnecting a vent line in an RV or outbuilding, this is the everyday fitting you reach for.

Build and dimensions

The part is as it should be: square, cleanly molded hubs with uniform wall thickness and a smooth interior finish. On the bench, both hub mouths had consistent chamfers that help guide the pipe in without catching, and the stop in the middle is crisp—useful for setting insertion depth by feel when you can’t see the mark.

A note on sizing: “1-1/2 in.” is the nominal pipe size. The coupling’s hub is sized to fit over the pipe’s outside diameter, not the pipe’s nominal inside diameter. In other words, the coupling goes over pipe, not inside it. If you’re measuring with a tape and wondering why nothing is exactly 1-1/2 in., that’s normal for DWV fittings.

Installation experience

My first use was a kitchen drain repair where a wayward screw had pierced the ABS waste line in a cabinet wall. I cut out a short section and used this coupling on one end with a short repair piece and a second coupling on the other end. The process was straightforward:

1. Cut square and deburr. I use a fine-tooth saw and a quick pass with a deburring tool. A slight bevel on the pipe edge helps the pipe slide into the hub and spreads cement evenly.
2. Dry fit and mark insertion depth. I score a line on the pipe where it bottoms out in the hub—critical for full engagement.
3. Clean the surfaces. Wipe away dust and any oils. ABS doesn’t require primer, though your local code may specify a specific cement or a one-step cleaner.
4. Apply ABS cement evenly to the pipe and lightly to the hub. Don’t skimp, but don’t puddle it either.
5. Push fully home and give a quarter turn. Hold pressure for 10–15 seconds to prevent push-back.

The joint grabbed as expected—ABS cement sets fast—so alignment planning matters. After cure, the interior transition felt flush and smooth with a finger, which is what you want for unobstructed flow. A similar experience on an RV tank vent recoupling confirmed the same: quick, predictable bond, no drama.

Performance in service

A solvent-welded ABS joint essentially fuses the materials, resulting in a strong, chemically resistant connection. Once cured, the joint becomes part of the pipe. I’ve had zero weeping, no loosening, and no signs of softening around typical household chemicals, soaps, or temperature swings from warm dishwater to cold inflow. The smooth bore helps keep lint and biofilm from building at the joint—a small but real benefit over rougher castings.

It’s worth emphasizing: this is a DWV coupling. It’s not intended for pressurized lines. If you need flexibility or a serviceable joint in a tight retrofit, a shielded no-hub coupling might be a better fit. For permanent, rigid, in-system repairs and new work, this NIBCO coupling is the right tool.

Code and compatibility notes

• Material: ABS only. Don’t solvent-weld ABS directly to PVC with standard cements. If you’re transitioning, use an approved transition cement or a mechanical coupling listed for the purpose.
• Primer: ABS typically uses a one-step cement and doesn’t require primer, unlike PVC. Always follow local code and manufacturer instructions.
• Standards: The coupling is marked to ASTM D2661 (ABS DWV pipe and fittings) and D3311 (DWV fitting patterns), which is the baseline most inspectors look for.
• Exposure: ABS doesn’t love UV. If it’s in sunlight (say, on an exterior vent run), paint it with a UV-rated paint per code and manufacturer guidance.

Where it shines

• Everyday repairs: Cutting out a cracked or punctured section under a sink and dropping this in with a short nipple is as simple as it gets.
• Vent stacks: Light weight and quick set time are helpful when you’re on a ladder aligning multiple fittings.
• Clean, permanent joints: The interior smoothness and square shoulders contribute to neat, laminar flow in DWV systems.

What I’d watch for

• Alignment window is short. ABS cement grabs quickly. Dry fit thoroughly and mark your orientation before you open the can.
• Not for misaligned gaps. This isn’t a flexible coupling; it won’t correct offsets or out-of-square cuts. If your pipe ends aren’t coaxial, fix that first or use a repair coupling designed for misalignment.
• One-way decision. Solvent-welds are permanent. If you anticipate future disassembly, choose a mechanical option with clamps.

Practical tips

• Measure twice, cut once—and then chamfer. A tiny bevel on the pipe edge makes the difference between a clean slide and a smeared, over-wiped cement job.
• Use the depth stop. Bottom the pipe firmly to the hub stop and hold. If it backs out even an eighth of an inch while curing, you’ve lost contact area.
• Wipe squeeze-out. A quick wipe with a rag keeps the exterior neat and also helps you spot any voids in the bead.
• Check for true. A torpedo level laid along a long run after the joint sets helps you confirm pitch and alignment before the cement fully cures.

Durability and value

NIBCO’s DWV fittings are reliably molded and dimensionally consistent, and this coupling is no exception. The black ABS stands up to household drain chemicals and the temperature swings typical of sinks and showers. I don’t see flashing or molding imperfections, and the hubs are clean and true, which matters when you’re making back-to-back joints in tight spaces. As a basic, single-piece fitting, it’s also cost-effective, and because it’s a common size, it’s easy to keep one or two on hand.

Alternatives to consider

• Shielded no-hub couplings: Great for joining dissimilar materials or when you need a bit of forgiveness in alignment. Not as rigid, and not solvent-welded.
• Slip repair couplings (telescoping): Useful when you can’t move pipe laterally, though they add complexity and more potential leak points.
• PVC equivalent: If your system is PVC, stay with PVC for compatibility and code compliance.

Final thoughts

This ABS DWV coupling is the straightforward, dependable option I expect from a major brand. It installs cleanly, holds tight, and keeps the interior flow path smooth. For repairs and new runs in ABS drain and vent systems, it’s the kind of unflashy part that makes the rest of the job easier.

Recommendation: I recommend this coupling for anyone working in ABS DWV systems who wants a reliable, code-compliant, solvent-weld connection. It’s dimensionally consistent, quick to install, and durable in service. Just be mindful of alignment, use the correct cement, and reserve it for non-pressurized applications.