Horsepower Ratings

Determining a belt’s HP rating requires more than just knowing the belt type. Speed, pulley sizes, belt length, wrap angle, and other factors affect the HP rating. Speed affects the HP rating because as speed decreases, torque increases, so the HP rating must also decrease. Larger pulleys improve the belt’s HP rating because less tension in the belt is needed to transmit the torque. Synchronous belt HP ratings are based on having at least 60° of wrap and 6 teeth in mesh. V-belt ratings increase as wrap increases. HP ratings also include a length correction factor. Longer belts have higher HP ratings because they are used with larger pulleys and/or larger center distances, which decreases bending fatigue in the belt.

The easiest method to calculate a belt’s HP rating is by using our software Design Flex Pro or Design IQ. You can also use the tables and equations in our Drive Design Manuals. 

Belt horsepower ratings are used for designing belt drives. Always remember to design a drive with an appropriate service factor based on your application.

Gates Poly Chain Belts Power Courtney Force to Win in 1st NHRA Event of Season

Courtney Force, driving the Traxxas Funny Car with the John Force Racing team, won the Funny Car class of the first NHRA competition of the year, the O’Reilly Auto Parts NHRA Winternationals held in Pomona, CA. Gates Corporation is a sponsor of John Force Racing. “It was definitely unbelievable,” Force said. “My team, [crew chiefs] Ron Douglas and Dan Hood, thanks to them, they had given me a great race car all weekend long. I just try to keep it straight down the center, and they really made my job easy. I really owe it to those guys. It was kind of bittersweet finishing here [at the Automobile Club of Southern California NHRA Finals in November] and not getting that win, then coming back and picking up where we left off and finishing our job. We got the win, and I’m just proud of my team.” The Top Fuel and Funny Car classes use Poly Chain belts to drive the superchargers necessary to achieve the enormous horsepowers required to make the 1000' runs in 4 seconds or so. The Poly Chain belts used are specifically engineered for the extreme conditions of the application.

NAHBS - North American Handmade Bicycle Show

If you’re familiar with bicycles, you’re probably familiar with Gates Carbon Drive.  Gates Carbon Drive has been a viable bicycle chain replacement now going on 6 years.  Carbon Drive has made a pretty big impact on the industry, and a large part of the reason that they have been so successful is the adoption of the belt drive technology by small frame builders.  These builders tend to lead the industry to new ideas and solutions because of their ability to try new things, or change direction easily.  This month here in Denver, we are lucky enough to have a gathering of these frame builders at a show called NAHBS.  NAHBS stands for North American Handmade Bicycle Show.  Gates Carbon Drive is very excited to be a main sponsor of this great event.  Beyond just standard sponsorship, they are also hosting a design contest with more than $11,000 in cash and prizes to be given out.  NAHBS is open to the public, and a great way to see some beautiful and innovative bicycles.  If you’re in the Denver area the weekend of February 22^nd 2013, you should stop by.  Come shake hands with the employees of Gates Carbon Drive!  For show information please visit: http://2013.handmadebicycleshow.com/

ACHE Sprocket Corrosion

More and more often, synchronous drives (especially our Poly Chain GT Carbon belting and sprockets) are being utilized in ACHE applications.  Rust buildup is a common problem on the metal drive components of these cooling tower systems given the high ambient moisture content.  This rusting results in improper belt tooth meshing, premature belt tooth wear, loss of tension, and subsequent decreased belt life.

For these applications, nickel plating of both sprockets as well as rust resistant bushings are recommended to inhibit this corrosion and increase the belts performance and life.  For assistance in obtaining nickel plated sprockets and rust resistant bushings contact Gates Made-To-Order Metals team at (800) 709-6001.

Standard & Non-Standard Shaft Key Sizes

When preparing to install sheaves or sprockets using either TaperLock or QD bushings, it is helpful to know what key sizes will be needed so key stock material can be obtained in advance.  While this information can be found in various industry publications, it is not often presented in a direct and concise form.  The following table includes standard rectangular shaft key sizes for shaft diameters ranging from 5/16" to 9":

 Standard rectangular key stock is readily available from most Gates Industrial Distributors.

As bushing bores approach the maximum recommended diameters, keyway depths are reduced in order to extend maximum bores as much as possible.  Reduced keyway depths then require special non-standard shallow shaft keys.  Because these special shaft keys are not readily available, the appropriate size is included with each bushing.  The special non-standard shaft keys required for TaperLock bushings are included in the following table:

This table includes the specific bushing size that each bore range and non-standard shaft key correspond to for handy reference.

The non-standard shallow shaft key sizes used for QD bushings are not all the same as for TaperLock bushings and bore ranges differ, so the following table includes special non-standard shaft keys required for QD bushings:

This table also includes the specific bushing size that each bore range and non-standard shaft key correspond to for handy reference.

A valuable part of every installation job is obtaining all needed components and then confirming that those received are correct.  These tables will enable installers to quickly confirm shaft key sizes needed for both TaperLock and QD bushings over a broad range of bores.
Feel free to contact us at ptpasupport@gates.com or 303-744-5800 if you have any questions.