Ads 18850020dw Dual Wall Pipe 18in X 20ft N-12 Bell End

Product Description

The ADVANCED DRAINAGE SYSTEMS 18850020dw is an 18-inch nominal, solid dual-wall corrugated polyethylene pipe engineered for high-load underground drainage applications. Part of the N-12 Series, it features a smooth interior wall for maximized flow capacity and a corrugated exterior wall for structural strength. The bell end connection accepts a spigot for field-assembled, watertight joints using the Solidtight system. Inside diameter measures 18 inches, outside diameter measures 22 inches, and each stick runs 20 feet. Material meets ASTM D3350 standards for polyethylene pipe compounds. Temperature rating spans -10 to 120 degrees F, making it suitable for a wide range of burial environments.

This pipe is used in residential, commercial, and municipal stormwater management systems. Typical applications include culverts, detention and retention systems, storm sewer mains, and subsurface drainage laterals. The 20-foot straight length minimizes joints in long runs, reducing labor time and potential leak points. Licensed plumbers, site contractors, and civil construction crews routinely specify N-12 dual-wall pipe for gravity-flow drainage projects requiring both hydraulic efficiency and structural integrity under deep-burial or traffic-load conditions.

Key Features

• Solid dual-wall construction: smooth interior bore for flow efficiency, corrugated exterior for load resistance
• N-12 Series designation meeting ASTM D3350 polyethylene material standard
• 18-inch inside diameter and 22-inch outside diameter in a 20-foot straight length
• Bell end x spigot Solidtight connection for field-assembled, watertight joints
• Temperature rated from -10 to 120 degrees F for varied burial conditions
• Black polyethylene construction resists corrosion, rot, and chemical degradation

Compatibility

Designed for use within the ADS N-12 Series Solidtight pipe system, where bell end pipe sections accept standard N-12 spigot ends and compatible gaskets to form watertight joints.

Installation Notes

Installation of 18-inch dual-wall pipe should be performed by qualified site contractors or licensed plumbers following applicable local codes and ASTM installation standards for buried thermoplastic pipe. Trench bedding, haunching, and backfill compaction are critical to maintaining pipe shape and load distribution — follow the project engineer's specifications for embedment material and compaction density. Confirm joint gaskets are properly seated and lubricated before pushing spigot into bell. Never exceed the pipe's rated burial depth without verifying structural adequacy with the manufacturer's load tables.