The first key decision before installation is to choose […]
The first key decision before installation is to choose the correct belt type for your application. The belt type is an important aspect to take into account, as it allows major cost savings.
In the industrial and commercial sectors, one in three electric motors use belt drives. However, some customers fail to take advantage of the potential energy cost savings of certain industrial belts, which are readily available and cost -efficient. While pulleys control the speed of the equipment, industrial belts are designed to position the motor relative to the load. High efficiency and low maintenance are key components to top performing belt transmission systems.
V-belts are the most commonly used belt drives. Using a trapezoidal cross section, V-belts create a wedge action on pulleys to increase friction and improve the belt’s power transfer capability. A V-belt drive works when friction between the side of the belt and sheave causes the shaft to rotate. The equations using this friction are beyond the scope of this paper but they are based on Euler's equation is accurate for a flat belt drive but is only a gross approximation for a V-belt drive, even with the inclusion of factors to account for groove angle and wedging.
It is not accurate for speed-up drives which will be discussed later. It is important to note that current industry practice for selecting belts is based on the extension of Euler is the effective diameter of the sheave, which is used to determine the pitch length of the belt for center distance calculation. The drive ratio is the driver speed divided by the driven speed. 'Hub load'is the result of belt tension, which is the vector sum of the tight side ten-sion and the slack side tension. Hub load is directly propor-tional to the horsepower and indirectly proportional to the product of RPM and pitch diameter. The greater the hub load the lower the bearing life.
Heavy loads often require joined or multiple belts. At the time of installation, V-belts have 95% to 98% peak efficiency. Pulley size, driven torque, under or over-belting, and V-belt design and construction impact efficiency. V-belts have a nominal efficiency of 93%, a reduction of 5%, over time if slippage occurs because the belt is not periodically re-tensioned.
Cogged belts have slots that run perpendicular to the belt’s length, helping to reduce the bending resistance of the belt. While using the same pulleys as v-belts, cogged belts manage to run cooler, last longer, and increase efficiency by 2% from standard v-belts.
Synchronous belts, often referred to as timing belts, boast a 98% efficiency, which is maintained over a wide load range. These toothed belts require the installation of mating tooth-drive sprockets. Synchronous belts require less maintenance and re-tensioning, operate in wet and oily environments and run slip-free. While synchronous belts are the most efficient, they can be noisy, transfer vibrations, and are unsuitable for shock loads. In such applications, cogged belts are the better choice.You can click www.automotivedrivingbelt.com to see more information.