Timing Belt Pulley Pitch Diameter Charts

Timing belt pulleys are one of the most commonly utilized mechanisms for machinery in a wide variety of industries – from aerospace and robotics to wire processing and automation.

However, when a new timing belt pulley is needed, finding the right mechanism can be challenging! Most pulley manufacturers utilize timing belt pulley pitch diameter charts to display available options.

Understanding how to read these charts and extract data is not always a simple process. In the content below, we seek to guide customers in comprehending timing belt pulley pitch diameter charts.

1. Select the Proper Pitch

The first step to properly reading timing belt pulley pitch diameter charts is straightforward: select the right chart! Most timing belt pulley pitch diameter charts are organized by pitch.

Timing belt pitch is simply the distance between one tooth and another. Some timing belts have profile or pitch etched into the rubber. However, some don’t! If you’re unsure of the pitch of the belt you need, simply measure from the crown of one tooth to the crown of the next tooth in inches or millimeters.

2. Choose the Proper Pulley

Once you know the pitch of the pulley you need and have identified the proper chart, you can search the chart for the proper item needed.

Timing belt pulley pitch diameter charts contain three primary data points: number of teeth, pitch diameter, and outside diameter (OD). Knowing the number of teeth, pitch diameter, and outside diameter needed is critical for knowing the requirements of your timing belt drive system.

Number of Teeth: this number indicates the number of teeth on the pulley.
Pitch Diameter: is a rather technical measurable. In essence, this number measures the diameter of the timing belt in each groove (i.e. the distance between the pitch and the timing belt pulley). As mentioned, the pitch of a belt is the distance between teeth. Pitch diameter can be found with a simple calculation: (pitch x number of teeth)/ Pi (3.14159).
Outside Diameter (OD): outside diameter is also known as OD. OD is simply the distance from one edge of the pulley to the other. To identify OD, simply lay the circle of the pulley flat and rest a ruler along the top. For best measuring results, use a micrometer.

What Other Factors Should You Consider When Purchasing Pulleys?

Navigating timing belt pulley pitch diameter charts is the first step in identifying the proper timing belt pulley for your application. You may know precisely what material you need the pulley to be fashioned from. Once you have selected the proper size, you are ready to purchase.

In some cases, determining the size is only your initial step in project planning. We wrote a guide on timing belt pulleys, including how to choose the best one for your project! Below, we’ll summarize our findings.

Environmental Concerns

Consider the environment your pulley will operate in. Depending on the industry and application, your pulley may need to be food-safe or anti-static. If your environment is hostile, certain materials should be chosen as well.

Is your environment extremely hot or cold? Will the pulley be bombarded with large dust particles or debris? If the pulley will be exposed to grease or oil, a urethane belt is often the best option.

In short, select the best material for the work environment of the pulley.

Material Considerations

Environmental conditions will impact the material chosen for your pulley system. A few of the most common pulley materials are aluminum, steel, and plastic. Each are best suited for differing environmental circumstances.

Aluminum is light, durable, and utilized most often in high horsepower drive systems. Aluminum can withstand extreme temperatures.
Steel is also excellent for extreme environmental conditions, such as extreme heat or cold. The strength of steel allows for heavy load capacity.
Plastic is lightweight and affordable, often utilized in neutral environments. Plastic should be used for light applications and does not require extensive maintenance.

IPG: Custom Pulley Manufacturers

At Illinois Pulley & Gear, we emphasize customer service and quality parts. Part of our customer service promise is helpful transparency – we are quick to answer questions and assist in finding the right part for your needs.

Unable to find the pulley you’re looking for on our pitch diameter charts? No problem! We are here to help you. Give us a call at 847-407-9595 or complete our online contact form! We regularly help customers identify which pulleys they need, often crafting customized pulleys according to precise specifications.