4 inch Cast Iron Soil 1/8 Bend No Hub x No Hub

4" Cast Iron Soil No Hub 1/8 Bend – Fitting for Directional Change in DWV Systems

The 4" no hub cast iron 1/8 bend is a drainage fitting used to redirect flow at a 45-degree angle in soil, waste, and vent systems. Manufactured in accordance with ASTM A888 or CISPI 301 standards, this fitting is suitable for gravity-fed drainage applications in residential, commercial, and institutional construction.

Constructed from high-strength cast iron, this fitting offers superior crush resistance, flame resistance, and sound attenuation compared to alternative materials. The no hub design enables straightforward installation using shielded couplings, which are torqued to specification to ensure a tight, leak-free seal without threading or welding.

Product Specifications

• Material: Cast Iron per ASTM A888 / CISPI 301
• Size: 4 inches nominal pipe size
• Bend Angle: 1/8 bend (45 degrees)
• Connection Type: No Hub – compatible with stainless steel shielded couplings
• Application: DWV (Drain, Waste, Vent) systems – non-pressurized

System Benefits

• ✅ Noise Reduction Cast iron’s mass dampens airborne and structure-borne sound in multi-story plumbing systems
• ✅ Fire Resistance Non-combustible material meets fire code standards without additional insulation
• ✅ Installation Flexibility Allows for directional adjustments in limited-space applications
• ✅ Structural Integrity Withstands external loading and soil settlement in below-grade installations
• ✅ Long Service Life Engineered for decades of performance in properly designed and maintained systems

Installation Guidance

Fitting must be joined using no hub couplings that meet ASTM C1277 or CISPI 310 requirements. Couplings should be tightened with a calibrated torque wrench to 60 in-lbs, per manufacturer instructions. Ensure all mating surfaces are clean and properly aligned prior to assembly. Always follow applicable plumbing codes such as IPC, UPC, or local amendments.

Typical Applications

This 1/8 bend is used in the following contexts:

• Underground sanitary and storm drain systems
• Vertical to horizontal transitions in soil stacks
• Offset layouts in building drains where standard 90° elbows are not suitable
• Low-noise drainage systems in hotels, hospitals, and multifamily housing

Additional Notes

Cast iron is recyclable and supports sustainable construction practices. Its performance under load and temperature extremes continues to make it a preferred material in engineered plumbing systems.

The 4" cast iron soil 1/8 bend no hub fitting delivers reliable, code-compliant performance in drainage layouts requiring smooth, gradual directional change. Its robust construction and compatibility with standard no hub couplings ensure efficient installation and long-term durability in both above- and below-grade environments.