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RADIUS BELT - TRANSMISSION

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The RA belt in a straight conveyor is normally driven by toothed sprockets that engage with the bracket edges on the sides of the belt.  The belt spacing must be supported approx. every 200 mm by smooth rotating rollers. The strength of the belt is determined by the strength of the brackets. The spiral filling, whether present or not, is to support the product. The belt itself is usually supported by wear strips under the spirals. Depending on the product load, the belt's own weight and the production process, these profiles can be applied every 150 - 400 mm.

For the RA belt the same applies to a curved conveyor as to a straight conveyor, with the difference that the RA-FD belt (inner radius of 1.1 x the bandwidth) is driven through sprockets in the bracket on the inner radius and the bracket in the middle. The inner radius of each curved conveyor is determined by the design of the belt and brackets. Depending on the choice, this can be 1.1, 1.7 or 2.2 x the bandwidth. When constructing a curved conveyor, one must take into account that there is a straight entry and exit at the curve. This is to allow the belt, which has merged on the inside of the bend, to stretch. This straight entry and exit length is recommended at a minimum of 1.5 x bandwidth. The belt can also try to get into the drive and return wheels a little in advance. The inner radius of the curved conveyor itself will have to be custom-made. The belt must have space inside the frame on the outer radius to deviate. A minimum space of approximately 50 mm is desired. This space can be used to optimally adjust the belt. It should be noted that the friction of the belt on the inner radius in combination with the weight of the belt and the product weight can quickly increase the tensile force in the outer (or middle) bracket. It is important to keep friction low on the inside of the bend. In the most extreme  In this case, a moving internal guide may be necessary.

The RA belt in a spiral tower is the most commonly used application. In short, a spiral tower is a special curved conveyor in which the belt rests against a driven inner drum. The friction of the drum on the belt ensures that the belt is carried along in the spiral tower. An auxiliary drive (take-up drive) will be installed at the end of a spiral tower. This auxiliary drive, as it were, pulls the first piece of tape tight around the driven drum, causing it to take the rest of the tape along with it. It is important that this drive delivers a constant driving torque. This driving torque must be adjustable and set as low as possible to a constant value. A minimum of drag force increases the lifespan of the belt. The speed of the auxiliary drive is always set slightly higher than the requested belt speed.  Because the belt is frictionally carried by the drum (slip), in a rotating installation the belt on the inside of the belt will lag slightly behind the speed of the drum. The maximum tensile force occurs in the outer bracket of the standard belt and in the center bracket of the RA-FD belt.

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