HDPE Pipe Sizes

At WL Plastics, we manufacture high-density polyethylene (HDPE) piping in sizes ranging from ¾” to 54” diameters. Depending on the application and required specifications, HDPE pipes come in IPS, CTS, DIPS, and SIDR sizes.

HDPE Pipe Sizes From WL Plastics

We carry a range of pipe sizes to suit various applications. The following resources are helpful when selecting the right pipe size for a specific application:

• WL 102. This size chart lists the IPS (Iron Pipe Size) pipe sizes and pressure class ratings for our HDPE 4710 pipe with IPS sizes ranging from ¾” to 54”.

• WL 104. This size chart lists the DIPS (Ductile Iron Pipe Size) and DIOD (Ductile Iron Outside Diameter) pipe sizes and pressure class ratings for our PE4710 pipe. The chart includes DIPS sizes ranging from 4 to 36.

• WL 116. This PDF provides helpful information about WL Plastics pipe standards. It includes tables with outer diameter (OD) size and dimension ratio (DR) for piping in various industries.

• WL 129. This document provides IPS and CTS (Copper Tubing Size) sizes for gas distribution piping per ASTM D2513.

• WL 130. This resource provides IPS and DIPS pipe sizes for Class 200, 250, and 335 PE4710 FM Approved Pipe, including IPS sizes ranging from 2 to 36 and DIPS sizes ranging from 4 to 36.

• WL 130M. This PDF lists the metric pipe sizes available for Class 200 (13.8), 250 (17.2), and 335 (23.1) PE4710 FM Approved Pipe, with metric sizes ranging from 50 to 1000.

What is an IPS Pipe?

Iron Pipe Size (IPS) is the original pipe sizing system, first developed in the early 19th century. IPS was created to standardize pipe diameters for industrial use and remains a widely used system today. IPS HDPE pipes are typically measured by their nominal outside diameter (OD) and are commonly used in:

• Oil and gas gathering
• Natural gas distribution networks
• Mining operations
• Certain potable water and wastewater systems 

IPS pipes are valued for their durability, versatility, and compatibility with a wide range of fittings and couplings, making them a reliable choice for industrial applications.

What is DIPS Pipe?

Ductile Iron Pipe Size (DIPS) was introduced in 1948 to address the need for a consistent inside diameter (ID), allowing better flow calculations and easier jointing. DIPS is now the standard sizing system for potable water and sewer systems, and is particularly important where accurate internal pipe volume and hydraulic calculations are critical.

DIPS pipes are used in:

• Municipal water distribution
• Sewage systems
• Stormwater management

What Is CTS Pipe?

Copper Tubing Size (CTS) refers to pipes primarily used for small-diameter applications, measured by outside diameter. CTS HDPE pipes are common in:

• Gas distribution services
• Potable water lines
• Residential and commercial plumbing

CTS pipes are preferred for compact installations, offering ease of joining and reliable pressure handling in systems with lower flow requirements.

What Is SIDR Pipe?

Standard Inside Diameter Ratios (SIDR) measure the ratio of pipe diameter to wall thickness. SIDR pipes are primarily used for conduit and specialized industrial applications where maintaining a consistent inside diameter is critical.

While SIDR pipes can be used for potable water, they are rarely sold today and are being phased out. SIDR was removed from AWWA C901 in the 2020 revision due to declining demand and the prevalence of SDR/DR-based sizing systems.

What is SDR and DR?

Standard Dimensional Ratio (SDR) is a measure of a pipe’s outside diameter (OD) relative to its wall thickness. A higher SDR means thinner walls, while a lower SDR indicates thicker, more robust walls for higher-pressure applications.

Dimension Ratio (DR) is interchangeable with SDR and is often used in engineering and design specifications. Both terms describe pipe strength and pressure capacity, which is critical for proper system design.

Find out how to measure SDR.

What are OD and ID?

Most HDPE pipes are OD-controlled, meaning the outside diameter and wall thickness tolerances define the pipe size. This results in an average inside diameter (ID) that can vary slightly. Less common ID-controlled pipes have a specified inside diameter, causing the outside diameter to vary within tolerances.

OD-controlled pipes are the industry standard for most water, wastewater, and industrial applications, ensuring interchangeability with standard fittings and joints.

HDPE Pipe from WL Plastics

Our high-performance HDPE piping solutions offer reliable and durable performance for industries such as wastewater, potable water, mining, oil and gas gathering, natural gas distribution, and more. As a leading polyethylene pipe manufacture, our pipes are manufactured in accordance with strict industry standards using high-quality materials. With best-in-class manufacturing processes, a team of experienced personnel, and dedication to continuous improvements, WL Plastics is the ideal solution for your HDPE piping needs.

For more information about our HDPE pipe sizes, or to get started on your piping solution, contact us today.