Engineering a notched belt is definitely a balancing act between versatility, tensile cord support, and tension distribution. Precisely shaped and spaced notches help evenly distribute stress forces as the belt bends, thereby helping to prevent undercord cracking and extending belt life.

Like their synchronous belt cousins, V-belts have undergone tremendous technological development since their invention by John Gates in 1917. New synthetic rubber substances, cover materials, construction methods, tensile cord advancements, and cross-section profiles have led to an often confusing selection of V-belts that are extremely application specific and deliver vastly different degrees of performance.
Unlike toned belts, which rely solely on friction and can track and slip off pulleys, V-belts possess sidewalls that match corresponding sheave v belt china grooves, offering additional surface area and greater balance. As belts operate, belt pressure applies a wedging pressure perpendicular with their tops, pressing their sidewalls against the sides of the sheave grooves, which multiplies frictional forces that permit the drive to transmit higher loads. What sort of V-belt fits in to the groove of the sheave while operating under stress impacts its performance.
V-belts are produced from rubber or synthetic rubber stocks, so they possess the flexibility to bend around the sheaves in drive systems. Fabric materials of various types may cover the share material to provide a layer of protection and reinforcement.
V-belts are manufactured in various industry standard cross-sections, or profiles
The classical V-belt profile goes back to industry standards developed in the 1930s. Belts manufactured with this profile come in a number of sizes (A, B, C, D, Electronic) and lengths, and so are widely used to replace V-belts in older, existing applications.
They are accustomed to replace belts on industrial machinery manufactured in other parts of the world.
All the V-belt types noted above are typically available from manufacturers in “notched” or “cogged” versions. Notches reduce bending stress, allowing the belt to wrap easier around little diameter pulleys and enabling better temperature dissipation. Excessive high temperature is a significant contributor to premature belt failure.

Wrapped belts have an increased resistance to oils and intense temperatures. They can be utilized as friction clutches during start up.
Raw edge type v-belts are better, generate less heat, allow for smaller pulley diameters, increase power ratings, and provide longer life.
V-belts look like relatively benign and simple devices. Just measure the top width and circumference, find another belt with the same sizes, and slap it on the drive. There’s only 1 problem: that strategy is about as wrong as you can get.