ConCar Variable Speed Belts 22x8 - 675 Li

ConCar Variable Speed Belts 22x8 – 675 mm inner length – DIN 7719 / ISO 1604

The ConCar Variable Speed Belts 22x8 x 675 Li is a flank-driven variator belt according to DIN 7719 and ISO 1604 with a molded toothed underside. The transversely molded teeth are not a tooth profile in the sense of a toothed belt; they do not engage with the pulley. Their purpose is to reduce bending stiffness so that the belt can be bent even on small running diameters without the flanks tearing or the belt heating up due to internal flexing.

This length in the drive

With an inner length of 675 mm, this belt belongs to the short end of the 22x8 profile. Short belts complete significantly more revolutions at the same belt speed: at 20 m/s, this belt completes approximately 28.0 revolutions per second, each with two complete bending cycles. Therefore, the service life of short belts is almost always limited by the number of bending cycles and not by the tensile load. In such drives, pay particular attention to the smallest effective diameter and ensure that the belt tension is no higher than necessary.

For design and comparison with an existing belt, the three length specifications are important because manufacturers use different reference dimensions. The inner length (Li) is 675 mm; it is measured at the inner circumference of the belt and is the standard ordering dimension in Germany. The effective length (Ld) of 715 mm refers to the neutral axis and is the dimension used in many catalogs and drive calculations. The outer length (La) of 725 mm is measured at the back of the belt. With a profile height of 8 mm, the difference between the inner and outer lengths is 50 mm, which corresponds to twice the difference in circumference across the belt height. When replacing an old belt, always compare using the same reference dimension; otherwise, you can easily be off by several centimeters.

Dimensions and specifications

• Internal length (Li): 675 mm

• Effective length (Ld): 715 mm

• External length (La): 725 mm

• Profile: 22x8 according to DIN 7719 / ISO 1604

• Top width: 22 mm

• Height: 8 mm

• Flank angle: 25°

• Construction: open-sided, toothed

• Mixture: Chloroprene (CR)

• Tensioning material: Polyester cord

• Antistatic: yes, according to ISO 9563

• Temperature range: -30 °C to +80 °C

• Belt speed: up to 30 m/s

• Weight: 0.108 kg

• Article number: G422080675

• EAN: 4059213020615

• Manufacturer: ConCar

Structure and materials

In terms of materials, ConCar combines a chloroprene body with a polyester tensile member. This pairing is the industry standard for variator belts because it simultaneously fulfills two opposing requirements: The belt must be flexible enough to bend over a small diameter, yet stiff enough longitudinally to resist flexing under load. Antistatic treatment according to ISO 9563 is standard on ConCar belts and is not an additional cost option.

The 25° flank angle is the crucial difference compared to a conventional V-belt, which operates at 34 to 40 degrees. The shallower angle generates less wedging effect per millimeter of radial travel, ensuring smooth belt operation across the entire pulley adjustment range and preventing binding at the end positions. Simultaneously, the large upper width of 22 mm provides the necessary contact area to transmit torque solely through friction. The toothed underside reduces bending stiffness to such an extent that the belt can operate even on small effective diameters without the flanks overheating due to internal flexing.

Typical areas of application

Belts of this size are typically found in compact drives: bench drills and small lathes with continuously variable spindle speed, feed drives on band and circular saws, laboratory centrifuges and shakers, dosing and small conveyors in packaging lines, as well as garden equipment and small drives where the installation space does not allow for large pulleys.

What these applications have in common is that the rotational speed must be adjusted during operation to suit the material, batch, or demand. A Variable Speed Belts solves this problem purely mechanically, without any electronics in the drive train. This is advantageous wherever dust, moisture, vibration, or temperature would damage a frequency converter, and it remains the only economical solution for existing machines because the variator is an integral part of the machine's design.

Assembly and tension

For installation: Open the pulleys, place the belt on without tension, then adjust it to the required tension using the adjustment mechanism or the motor rocker. The belt must never be pulled over the pulley edge or pried open with a tool. After approximately 24 hours of operation, the belt will have settled; at this point, the tension should be checked a second time and adjusted if necessary. Insufficient tension leads to slippage and burns the belt edges, while excessive tension puts unnecessary stress on the bearings and tension members.

Transverse cracks on the underside indicate an insufficient bearing diameter or cold brittleness, while longitudinal cracks and frayed edges point to misalignment between the pulleys. It's worthwhile checking the alignment with a ruler or laser when changing the belt, as even a few millimeters of misalignment over a one-meter center-to-center distance can halve the belt's lifespan.

Similar names for other brands

Variable Speed Belts are standardized according to DIN 7719 and ISO 1604. A belt with a 22x8 profile and a 675 mm inner length is therefore dimensionally identical regardless of the manufacturer; no modification of the pulleys is required for replacement. This ConCar belt replaces, among others:

• OPTIBELT: VB 22x8 / VARIO POWER 22x8

• GATES: Multi-Speed ​​22x8 / Predator V Variable Speed

• CONTITECH: VARIO Speed ​​22x8 / CONTI-V VARISPEED

• MEGADYNE: VARISECT 22x8

• MITSUBOSHI: VARI-SPEED 22x8

• BANDO: Variable Speed ​​22x8

• PIX: Variable Speed ​​22x8

Delivery

The belt is supplied as a single, endless belt. Standard lengths and common profiles are available from stock; custom lengths and widths are available upon request. If you are unsure which length your drive requires, please send us the part number of your old belt or the dimensions of your pulleys, and we will check the compatibility.