V belts look like relatively benign and simple pieces of equipment. They’re basically a glorified rubber band, right? Need a replacement? Just measure the top width and circumference, find another belt with the same dimensions, and slap it on the drive. There’s only one problem: that approach is about as wrong as you can get.

Like their synchronous belt cousins, V belts have undergone tremendous technological development since their invention by John Gates in 1917. New synthetic rubber compounds, cover materials, construction methods, tensile cord advancements, and cross-section profiles have led to an often confusing array of V belts that are highly application specific and deliver vastly different levels of performance.

How V Belts Work

Unlike flat belts, which rely solely on friction and can track and slip off pulleys, V belts have sidewalls that fit into corresponding sheave grooves, providing additional surface area and greater stability. As belts operate, belt tension applies a wedging force perpendicular to their tops, pushing their sidewalls against the sides of the sheave grooves, which multiplies frictional forces that allow the drive to transmit higher loads. (Figure 2) How a V belt fits into the groove of the sheave while operating under tension impacts its performance.

V belts are made from rubber or synthetic rubber stocks, so they have the flexibility to bend around the sheaves in drive systems. Fabric materials of various kinds may cover the stock material to provide a layer of protection and reinforcement.

This article comes from powertransmission edit released