V belt drives are often considered the fuse of the power transmission drive path, which can be an advantage for v belt drives. In that line of thinking, not much thought is given to the impact on overall equipment reliability with respect to the v belt drives connecting driver and machine.

V belt drive design, v belt installation and v belt maintenance affect more than just the v belts, but the driver and machine as well. Machine components, such as shafts, bearings and seals, are some of the elements that will suffer from poor v belt reliability.

Chronic v belt failures and short life can increase valuable maintenance manpower, which is already under constant pressure in today’s environment. Unhealthy v belt drives also typically increase equipment vibration, which can negatively impact a component’s life, as well as processes. Poorly operating v belt drives are also energy wasters, as low power transmission efficiencies come along with poor reliability. Lastly, unreliable v belt drives carry with them a potential safety risk. Constantly working on v belt drives with multiple pinch points puts maintenance technicians in the line of fire for potential accidents.

A v belt drive must be designed correctly to have a chance at a full life in a 24/7 industrial application. Many v belt drive reliability issues have been traced back to an initial design problem. There are many v belt drive power transmission suppliers that offer online software to aid in v belt drive selection, although some are just designer’s choice, such as what type of v belt to use. However, there are several design factors that must be accurate because even good maintenance won’t correct them. For example, having enough v belts to transmit the connected horsepower (hp). This article concentrates on v belt drive maintenance, so it’s assumed the v belt drive design has no deficiencies.

This article comes from reliabilityweb edit released

Power transmission in linear motion designs is often through rotary-to-linear devices, chain, or belt drives. The earliest belt iteration — and one that’s still economical today — is the friction-based V-belt design. These pair a belt with a pulley (often on an electric motor’s geared output shaft) to provide reliable operation in myriad end-user and industrial designs.

Modern V belts are rubber, urethane synthetic, and neoprene designs with either a V or trapezoidal profile. The latter increases the amount of contact between V belts and pulleys to minimize tension needed to transmit torque. Even so, polyurethane outperforms rubber thanks to its higher resistance to chemicals and adaptability to specialized profiles. (Polyurethane also boosts the shear strength of the teeth on synchronous belts covered in this article’s next section).

A V belt’s most important element — its tension-bearing top — includes fiber cords for strength to bear the actual traction load. Modern tension-member cords are often aramide, polyester, fiberglass, or even steel. Pre-stretched variations help minimize stretch. The cords embed into the main belt material that serves to hold the belt body together and shed heat. The part of most modern friction belts that engages the pulley is a compression section designed to actually wedge into pulley grooves as a way to boost engagement. In many instances, a rubberized fabric cover helps protect the belt and prevent slipping and overheating cords.

Though they’re versatile and forgiving, improperly sized friction-based belt drives can slip (tangentially on the pulley — a form of lost motion) and creep axially. That can make for unreliable speed output. Here are some things to remember if a V-belt drive makes the most sense for a motion axis: Output torque depends on belt resistance to tension and belt-pulley adherence. The latter is why oils and greases must be kept away from belt drives — or threaten drive failure due to slipping.

Be prepared to specify V belts by cross section (including the belt’s top width, V angle, and depth) and overall pitch length (defined as a circumferential length along a belt’s pitch line). Then suitable V belts are narrowed further by which have sufficient power ratings (determined by rpm and sheave speed) to satisfy design demand of nominal horsepower (to be transmitted or output at the motor) with application of a service factor.

This article comes from linearmotiontips edit released

This v belt drive uses only v belts and is passed over the driver and driven pulleys. The open and cross belt drives are only possible with v belts.

The motion or power is transmitted from one shaft to another shaft by means of belts, i.e., these belts are used when the two shafts are apart at some distance.

Belt drives produce the least amount of noise and vibration.

When the belt is rotating in a clockwise direction or the belt motion is from driver to driven pulley or the belt is in forwarding motion, then the upper part of the belt is under sag, called as the slack side of the belt.

This portion is always under compression

The lower portion of the belt under tension is called as the tight side of the belt. There is a friction between the belt and pulley which provides the grip and enables the power to transmit between two pulleys.

In a belt-drive, the power transmission depends on the amount of friction between pulley and belt. The slip can be eliminated by running the v belt with a slower speed.

The pulley used for v belt drive is slightly crowned to avoid the belt from running out of it. Then the v belt can be run with higher speed.

The crowning of the pulley holds the v belt centrally. The effective pulling power of the belt causes the rotation of the driven pulley, and it is the difference between the tensions on tight and slack sides.

The materials used for the pulley are cast iron, steel, and steel alloys. For low speeds and light work applications, usually, wood is recommended.

The drive is obtained by using either v belts

V belt drives are suitable to transmit power from one place to another place when the distance between the two places or pulleys or shafts is larger, and v belts are for short distance.

The ends of the v belts are joined by using rivets, nuts, and bolts or joined by lacing or cementing methods. Wires are also used to join the v belt ends since this method is easier and joined quickly.

This article comes from mechathon edit released