ConCar Variable Speed Belts 30x10 - 1320 Li

ConCar Variable Speed Belts 30x10 – 1,320 mm inner length – DIN 7719 / ISO 1604

This ConCar Variable Speed Belts with a 30x10 profile and an inner length of 1,320 mm, is a toothed variator belt conforming to DIN 7719 and ISO 1604. Variable Speed Belts are the mechanical alternative to frequency converters: they regulate the output speed purely through geometry, without electronics, harmonics, or an additional heat source in the control cabinet. In many woodworking, textile, and agricultural machines, this remains the more robust solution because it operates reliably even in dusty, humid, and vibration-prone environments.

This length in the drive

With an inner length of 1,320 mm, this belt is one of the longer versions of the 30x10 profile. With two equally sized pulleys with an effective diameter of 315 mm, this corresponds to a center distance of approximately 190 mm. Long belts are less prone to bending stress; at 20 m/s, they rotate only about 14.7 times per second. However, they require more attention to tension: the slack side tends to flutter with large center distances, and the belt's own mass generates additional centrifugal force during operation, which reduces the contact pressure on the pulley.

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 1,320 mm; it is measured at the inner circumference of the belt and is the standard ordering dimension in Germany. The effective length (Ld) of 1,365 mm refers to the neutral axis and is the dimension used in many catalogs and drive calculations. The outer length (La) of 1,383 mm is measured at the back of the belt. With a profile height of 10 mm, the difference between the inner and outer lengths is 63 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): 1,320 mm

• Effective length (Ld): 1,365 mm

• External length (La): 1,383 mm

• Profile: 30x10 according to DIN 7719 / ISO 1604

• Top width: 30 mm

• Height: 10 mm

• Flank angle: 27°

• 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: 0.436 kg

• Article number: G430101320

• EAN: 4059213022268

• Manufacturer: ConCar

Structure and materials

The belt consists of a chloroprene blend (CR) with an embedded polyester tensile cord. Chloroprene was deliberately chosen here: it is resistant to oil mist, ozone, UV radiation, and weathering, and retains its elasticity in a temperature range of approximately -30 to +80 degrees Celsius. The polyester cord absorbs the tensile forces and keeps elongation low over the belt's lifespan, which is particularly important in a variator because an elongated belt length directly translates into a shift in the control range.

The 27° 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 30 mm upper width 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 cover the classic field of industrial variators: feed and grinding belt control in woodworking machines, demand-controlled piston and screw compressors, spinning and drawing units in textile machines, industrial mixers and kneaders with soft start, take-off and screw drives on plastic extruders, as well as boring mills and lathes with stepless control.

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

Before ordering, check the adjustment range of your drive. The belt must be able to be fitted without force, whether the pulleys are fully closed or open. After fitting, tension the belt to the tension specified by the machine manufacturer and check again after the break-in period. If several belts run in parallel in one drive, they must always be replaced as a complete set, as a new belt, in addition to worn ones, bears the entire load.

A typical wear pattern in the variator is glassy, ​​shiny edges. This is not a sign of aging, but rather slippage: the belt slips under load and polishes the edge. The cause is almost always insufficient tension or a worn pulley with an enlarged groove width. If only the belt is replaced and the pulley remains the same, the damage usually recurs within a few weeks.

Similar names for other brands

Variable Speed Belts are standardized according to DIN 7719 and ISO 1604. A belt with a 30x10 profile and an inner length of 1320 mm 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 30x10 / VARIO POWER 30x10

• GATES: Multi-Speed ​​30x10 / Predator V Variable Speed

• CONTITECH: VARIO Speed ​​30x10 / CONTI-V VARISPEED

• MEGADYNE: VARISECT 30x10

• MITSUBOSHI: VARI-SPEED 30x10

• BANDO: Variable Speed ​​30x10

• PIX: Variable Speed ​​30x10

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.