What's the Difference Between GT, GT2, and GT3?

Gates currently offers Poly Chain GT Carbon belts that are designed to run in Poly Chain GT2 sprockets. There are also PowerGrip GT3 belts designed for PowerGrip GT2 sprockets. What's with the GT, GT2, and GT3?
It's easy to get caught up in the product line names, but don't let it throw you off. "GT" stands for "Gates Tooth" which describes the belt's patented curvilinear tooth profile. The reason there are GT, GT2, and GT3 products is because there have been changes in the construction of the belts and sprockets over the years. For example, Gates is now selling the third generation of PowerGrip belts with the GT tooth profile. That product line's corresponding sprockets are on their second generation. That's why PowerGrip GT3 belts are used in PowerGrip GT2 sprockets. 
This applies to Poly Chain components as well. Poly Chain GT and Poly Chain GT2 belts had aramid tensile cords. The current third generation of Poly Chain belts use carbon tensile cords, hence the product line name "Poly Chain GT Carbon". The sprockets are currently on their second generation which is why Poly Chain GT Carbon belts are used in Poly Chain GT2 sprockets. 

Poly Chain GT Carbon Length Tolerance

We occasionally receive inquiries regarding the length tolerance for our Poly Chain GT Carbon belting.  This can arise out of simple curiosity or when a customer is concerned with designing a fixed center drive and wants to ensure they account for any length tolerance.  It is important to note that the actual tolerance for belt length comes by way of a center distance tolerance.  This center distance tolerance is used as a more functional value given the belt length is a pitch length which is nearly impossible to measure directly.  The most functional way to measure the belt length is to use specially machined measuring sprockets with the belt installed and then determine the center distance and compare it to the nominal value.  Given this, below is chart from our Poly Chain GT Carbon Drive Design Manual which outlines the center distance tolerance per belt length range.  

It is important to note that these values would need to be compared using specially machined measuring sprockets and should not be referenced when using standard, off the shelf sprockets as these table values do not account for sprocket manufacturing tolerances.  

For any additional questions feel free to look through our other blog topics or contact us at ptpasupport@gates.com or 303-744-5800.

Standard Calculations

Our drive design manuals are full of great information.  In the back of our drive design manuals, we have pages with standard calculations you may need when designing or modifying a belt drive.  For instance, below is the page out of our Poly Chain Drive Design Manual.  You can download our drive design manuals here.

Why Stainless Steel Poly Chain® GT®2 Sprockets and Bushings with Carbon Steel Screws?

Did you know that Gates carries a limited line of stainless steel sprockets for 8mm pitch Poly Chain^® GT^® Carbon™ belts in 12mm and 21mm widths?  In addition, there is a standard line of stainless steel Taper-Lock^® bushings available for use with these sprockets.  This combination provides a nice corrosion resistant hardware package for use in wet or wash down applications where standard sprockets and bushings would rust and corrode.

It may be helpful to note that screws supplied with the stainless steel bushings are made of carbon steel rather than stainless steel material.  Carbon steel screws are used for their superior material strength, and zinc plated for corrosion resistance.  Stainless steel screws do not have the mechanical strength necessary to install and retain Taper-Lock^® bushings in Poly Chain^® GT^®2 sprockets.

For comments or questions, feel free to contact Gates Product Application Engineering at 303-744-5800 or ptpasupport@gates.com.

Easy Access To Technical Information For Gates Industrial Belt PT Products

It can be difficult navigating the large gates.com website when looking for information about industrial belt drive systems, particularly when users may not know exactly what they are searching for.  To help with this, we put together a micro site that can be accessed from http://www.gates.com/drivedesign.  This is our site for Industrial Product Application Engineering, and contains related technical information and drive design tools for Gates industrial belt drive systems. 

You can find links to drive design manuals and technical literature, drive design software, downloadable hardware drawings and models, white papers, the Gates Facts knowledge database, the PT YouTube Channel, and more.  And if you still can’t find what you are looking for, contact information for our Helpline phone, email and chat feature are included.

Bookmark the http://www.gates.com/drivedesign site so you can quickly find the technical  information you need about Gates industrial power transmission products.

Contact Gates Product Application Engineering with comments or questions at (303) 744-5800 or ptpasupport@gates.com.