General Overview of V-belts
V-belts are a type of power transmission belt characterized by their trapezoidal cross-section, which resembles the shape of the letter “V” when viewed in a cross-section. These belts are commonly used to transmit power between shafts in machinery and equipment.
The V-belt design originated in the early 20th century as an improvement over flat belts, which were prone to slipping due to them only working off of friction. The invention of V-belts revolutionized power transmission in various industries by providing a more efficient and reliable means of transferring power. This innovation significantly contributed to the industrial revolution by enhancing the efficiency and productivity of machinery.
V-belts find extensive use in a wide range of industrial and commercial applications, including but not limited to:
Automotive Industry: V-belts are commonly used in vehicles to drive components such as the alternator, water pump, power steering pump, and air conditioning compressor.
Industrial Machinery: V-belts are essential components in various types of industrial machinery, including conveyor systems, pumps, compressors, generators, and manufacturing equipment.
Agricultural Equipment: V-belts are utilized in agricultural machinery such as tractors, combines, harvesters, and irrigation systems for tasks like driving pumps, fans, and other components.
Power Tools: Many power tools, including drills, saws, and grinders, use V-belts to transfer power from the motor to the tool’s operating mechanism.
Common industries that use V-belts in their manufacturing processes include:
Automotive Manufacturing: V-belts are employed in the production of vehicles and automotive components.
Textile Industry: Textile mills utilize V-belts in spinning, weaving, and other textile manufacturing processes.
Paper and Pulp Industry: V-belts play a crucial role in papermaking machinery, including pulpers, dryers, and printing presses.
Food Processing: V-belts are employed in food processing machinery for tasks like mixing, conveying, and packaging.
With this introduction and understanding of V-belts, we can now begin to basically size our own V-belts for our uses, while having the knowledge of its history and purpose.
Measuring V-Belt Dimensions
There are 2 major dimensions required when measuring your pre-existing V-belt or sizing one for your application: outside circumference and width.
The outside circumference typically plays a role on how far apart your machines or pulleys can be away from each other.
The width has an impact on the maximum power rating of the V-belt, with the larger the width the higher the power rating.
We will first discuss how to measure the width of the V-belt since that’s the easiest step. Simply use a caliper and pinch along the width (short side) of the belt face. If you do not have a caliper handy, then you can use any measuring tool, like a tape measure, and place the top of the belt on the tape measure to measure its width:
For measurement of the circumference, we will cover two methods for if the V-belt is not on a pulley and if the V-belt is already on a pulley.
The easier method is when the V-belt is not on a pulley and you can hold it in any way. You start off my marking the V-belt anywhere on the width of the outside diameter. You then place the V-belt along a measuring device, like a taper measure, and then roll the V-belt along the measuring device. Use the mark you made on the width as the starting point, and then roll the V-belt like a wheel along the measuring device until you reach your starting mark again.
The last method of measuring a V-belt is if it is already on a pulley system. You can utilize the classic method of wrapping a string along the outside diameter of the V-belt to determine its circumference. Simply place the beginning of the string on the outside diameter of the V-belt, and then wrap it until it’s completely around the belt. You will then measure the string and that will be the circumference of your V-belt.
Description of Common V-belt Profiles
There is a wide assortment of V-belt cross-sectional profiles that are designed for the best fit of certain applications and use cases. The profiles can be broadly broken down into 4 major categories: standard, metric, fractional power, and narrow. We will briefly mention some profile and sizes for each aforementioned category and a short description of their best fit cases:
Standard Profiles: Belts crafted with the standard profile are available in a range of sizes (A, B, C, D, E) and lengths. They serve as versatile solutions, particularly for retrofitting V-belts in older, existing applications.
Metric Profiles: Metric V-belts adhere to rigorous international standards established by esteemed organizations like ISO (International Organization for Standardization) and DIN (Deutsches Institut für Normung e.V.). These belts are ideal for replacing belts on industrial machinery manufactured across the globe.
Fractional Horsepower Profiles: Designed for light-duty applications such as lawnmowers, snow blowers, and attic or furnace fans, the fractional horsepower V-belt profile features a thinner cross-section and a lighter gauge tensile cord. This construction ensures enhanced flexibility, enabling the belt to bend effortlessly around small sheaves.
Narrow Profiles: V-belts with narrow profiles (e.g., 3V, 5V, 8V) boast steeply angled sidewalls, facilitating increased wedging action and offering significantly higher load capacity, up to three times that of comparable standard V-belts.
MISUMI carries a variety of Gates V-belts for your industry application. Explore the selection here.
Works Cited
Gates Corporation. (2017, June 1). Guide to V-Belt Selection and Replacement. Retrieved from Power Transmission Engineering: https://www.powertransmission.com/articles/993-guide-to-v-belt-selection-and-replacement
How to Measure a Pulley Belt Size. (2023, March 19). Retrieved from wikiHow: https://www.wikihow.com/Measure-a-Pulley-Belt-Size
