Balance and Rim Speeds

Gates stock sprockets and sheaves are all given a static balance up to 6500 feet per minute.  This number is a rim speed, not an RPM.  The maximum RPM a particular sprocket or sheave can achieve is also affected by it's diameter.  The larger the diameter, the higher the rim speed, and if you exceed the 6500 ft/min limit, you need dynamic balancing to the particular speed you are trying to achieve.  Dynamic balancing is not a stock offering, but Gates does have a department called Made To Order Metals that can help you source specialty balanced metal.  You can get a hold of MTO Metals by phone at 1-800-709-6001, or by email at makemymetal@gates.com

Not sure what your rim speed is?  Use our free design software to have it calculated, or the equations below.

Here's what you need:

Diameter (inches)
RPM

First  calculate perimeter (inches): Pi * Diameter or 2 * Pi * Radius

Then calculate rim speed (feet per minute): Perimeter * RPM / 12

Don't Mix and Mismatch Your Pulleys and Bushings

All Gates pulleys and corresponding bushings use mounting screws with imperial threads. Even bushings with metric bores use imperial threads so they can still work with our pulleys. Buying bushings with metric bores from other suppliers may not work with Gates pulleys because they could have metric threads. To avoid this issue always source parts from your local Gates distributor.

Temperature Ratings and the new Super HC XP

We frequently get asked about the temperature capacity of our V-belts.  We actually have a chart in our Heavy Duty Drive Design Manual that shows the temperature ratings for our standard line V-belts.  However, our new product line, Super HC XP has an even wider temperature rating of -60F to 250F!

Belt Identification

Did your Gates industrial belt last so long that the label is no longer legible? If you have no record of what belt is used in your application then the Gates Belt ID Chart is a great resource to identify your belt. Once you know the belt type you can find the part number using our Industrial PT Catalog or online catalog.

Replacing 8YU Type Synchronous Belts

We occasionally receive requests to provide belt interchanges or recommend replacements for synchronous belts identified as 8YU.  The 8YU drive system was originally developed by Unitta, a Japanese company in partnership with Gates, for use in the automotive industry.  The system was later commercialized for industrial type usage and introduced to Asian industrial markets. 

The 8YU system uses a unique belt tooth and sprocket groove form that is not interchangeable with other industrial synchronous belt drive systems.  There are no standard belts, available from Gates or other manufacturers, that can be used in 8YU type sprockets. Replacement belts must be 8YU type, and can be obtained either from OEM equipment manufacturers or from Unitta directly.

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

TuffCoat Plating on Hydraulic Fittings

TuffCoat plating sets the global standard in both corrosion resistance and environmental friendliness. Gates has removed all hexavalent chromium from its plating process. This metal, common in industrial plating, is toxic to the environment. Gates engineered TuffCoat plating to be stronger and more resistant to corrosion, without the toxicity of hexavalent chromium.

TuffCoat plating is standard on MegaCrimp and GlobalSpiral couplings and when tested under SAE J516 and ASTMB-117 salt-spray conditions, TuffCoat plating provided more than 500 hours of protection from red rust formation – almost 700 percent better than the 72-hour SAE standard. The Gates coupling with TuffCoat plating shows no red rust formation. White patches on couplings are salt residue, not corrosion. 

For any additional questions feel free to look through our other blog topics or contact us at fppasupport@gates.com or 303-744-5070.

Minimizing Heat in V-belt Drives

The air temperature surrounding a belt drive is the ambient temperature. Operating temperature is the actual temperature of running belts. The operating temperature of belts always exceeds the ambient temperature.

Higher than recommended ambient and operating temperatures deteriorate rubber compound properties, leading to premature belt failures. However, there are ways to minimize the impact.

For high ambient temperature applications, increasing ventilation around the belt drive can help reduce belt operating temperatures. This can be accomplished by adding vents to belt guards, by adding fins to sheaves, or by providing a cooler external air source.

Belt slippage will increase operating temperature. If belt slippage is due to under-design, a re-design may be necessary to increase the capacity. If belt slippage is occurring on a properly designed drive system, the belt installation tension level may need to be increased or worn sheaves replaced.

If the heat source is within the belt drive system itself, re-designing may help. Some belt drive design tips to minimize heat generation are listed below.

• Select belt types with a higher ambient temperature range
• Use more belts to decrease the load per belt
• Use larger sheave diameters to reduce belt bending stresses
• Change to a smaller belt cross-section or use notched belts for increased flexibility