Conti Synchroflex AT20 GEN III 1500

Conti Synchroflex AT20 GEN III 1500 – precise PU timing belt for synchronous power transmission

With 75 teeth distributed over a pitch length of 1500 mm, the Conti Synchroflex AT20 GEN III 1500 is designed for precise transmission of rotation, stroke and position. The belt is cast endlessly in PU and has integrated steel cord tension elements that stabilize the length during normal operation. The nominal tooth pitch is 20 mm and the tooth profile must match the profile of the pulleys precisely. It is not sufficient that another belt has approximately the same length or width. The GEN III version is the reinforced high-performance construction with red high-performance polyurethane and denser, two-filament steel cord. It should therefore be treated as a separate product series and not as the usual standard version.

Key technical data

• Pitch length: 1500 mm
• Number of teeth: 75
• Tooth profile: AT20 GEN III
• Tooth pitch: 20 mm
• Material: cast polyurethane with steel cord
• Brand: Conti Synchroflex

These specifications can be used as a check against the marking on the old belt or against the machine's spare parts list. The pitch length is not necessarily the same as a measurement across the outside of the belt, and the number of teeth is therefore often the safest additional check. If in doubt, both the belt and timing belt pulleys should be examined before ordering a replacement.

Why the correct profile is crucial

The AT profile has been further developed from the classic T profile. The larger tooth volume provides a higher tooth shear strength, and the profile is designed for a favorable tooth engagement with reduced engagement shocks. This makes the AT series suitable when a drive must be compact and at the same time transmit motion precisely. Continental states that the AT profile can perform up to 50% more than a corresponding T profile, but the actual capacity always depends on width, discs, speed and load profile.

PU body and longitudinally stable traction elements

The endless PU construction combines low dead weight with high longitudinal rigidity. The steel cord tension elements are cast into the belt and are not intended to be exposed, damaged or sharply broken during installation. The wear resistance of the polyurethane and the strong bond to the cord are central to the belt's lifespan. Correct handling is therefore just as important as the correct choice of profile and length.

The construction behind this variant

The red GEN III construction is not just a color variant. It is developed with higher cord density and a special steel cord construction that provides increased tensile strength, better grooveing and the ability to carry higher loads. The catalog also specifies a temperature range up to +100 °C. Standard and GEN III must therefore be created and selected as separate products, even when the length and profile are the same.

Areas of application

Continental cites heavy-duty drives, textile machines, printing machines, machine tools and large industrial power transmissions as examples for this profile family. The examples describe the general area of ​​application of the profile, but do not constitute an approval for any specific installation. The final belt width and pretension must be selected based on the transmitted torque, starting and shock loads, operating time, pulley sizes, speed and the number of teeth in simultaneous engagement. For safety-critical or heavily loaded drives, an actual calculation should be made.

The discs are part of the overall solution

The number of teeth on the pulleys affects both the gear ratio, deflection and how many belt teeth carry the load. A small pulley may be necessary in a compact drive, but it should not be selected without considering the minimum profile requirements and any counter deflection. Use timing belt pulleys with 20 mm pitch and the correct AT20 GEN III tooth shape, and check that the flanges do not damage the belt edge.

How to avoid unnecessary wear and tear

When installing, the cord pullers must be protected against kinks and local pressure damage. The belt must not be pinched with pliers or a screwdriver, and it should not be folded sharply. Check that the pulleys have the same pitch and profile as the belt and that they are not worn out. A stable drive is achieved through the right combination of alignment, wrapping and calculated pretension.

The belt width is selected on the product page

The belt width is not written in the product name because the same pitch length is collected on one product page. The starting pu is 16 mm. Integer widths from 16 to 50 mm can be selected on this product page. The original supplier widths for this length are 16, 20, 25, 32 and 50 mm. Other intermediate sizes are offered as cut-to-sizes of the same type of timing belt sleeve when they are within the selection shown. The number of teeth, pitch length and profile do not change when the width is changed.

Wear patterns and troubleshooting

Early damage is often caused by conditions surrounding the belt rather than the material itself. Bent shafts, worn tooth grooves, foreign objects and incorrect pretensioning can all shorten the service life. In the event of a belt break, the pulleys should therefore be cleaned and inspected before the new belt is fitted. Also check whether load conditions or start-stop cycles have changed since the original design.

Maintenance-free does not mean control-free

Continental specifies a temperature range of up to +100 °C for the GEN III series. When operating close to the temperature limits, the drive must still be dimensioned according to the specific load and environmental conditions. The timing belt operates without lubrication, and oil or grease should therefore not be added to dampen noise. The polyurethane is described as resistant to aging as well as simple oils, grease and petrol and to certain acids and bases. In the case of permanent contact, cleaning chemicals or unknown media, material compatibility should be specifically clarified.

Checking when replacing

When replacing a spare part, the marking on the existing belt should be compared with the product name. Check the profile designation, pitch length, number of teeth, design and width. If the text on the belt has worn away, the number of teeth can be counted and the pitch can be assessed by measuring over several teeth. A single external length measurement is less reliable because the nominal length of the timing belt is indicated in the pitch line.

Answers to typical questions

Conti Synchroflex AT20 GEN III 1500: can the AT20 GEN III be used on a different tooth profile with the same pitch?

No, not without documented compatibility. The 20 mm tooth pitch describes the distance between the teeth, but the shape and clearance of the tooth flanks may differ. The belt must be used with pulleys manufactured to the AT20 profile. Visual similarity is not sufficient documentation.

Conti Synchroflex AT20 GEN III 1500: can an old V-belt be directly replaced by this timing belt?

No. A timing belt requires timing belt pulleys with the correct profile and pitch, while a V-belt works by friction in V-grooves. A conversion therefore requires new pulleys and a dimensioning of the entire transmission. The product is intended as a timing belt, not as a universal replacement.

Conti Synchroflex AT20 GEN III 1500: can a wider belt always transmit twice as much?

Not necessarily. A larger width provides a more active belt cross-section and can increase the permissible load, but the drive capacity also depends on the profile, number of teeth in mesh, pulley size, speed, load factor and preload. The width should be selected by an overall calculation.

Conti Synchroflex AT20 GEN III 1500: can the belt be shortened or assembled to a different length?

No. This is a cast endless timing belt with a fixed pitch length. It can be cut to width within the available options, but the circumference and number of teeth cannot be changed. If the length needs to be changed, a different cast belt size is required.

Conti Synchroflex AT20 GEN III 1500: does the number of teeth change when the belt width is changed?

No. All width choices on this product page have the same pitch length of 1500 mm and the same number of teeth of 75. Only the width of the belt, and thus the price and possible load capacity, changes. The width must still match the pulleys and the technical dimensioning.

Conti Synchroflex AT20 GEN III 1500: what does the pitch length of 1500 mm mean?

The pitch length is the nominal length measured in the belt cord line where the steel cord tension elements are located. It is not the same as a random outer circumference measurement. For this belt, 1500 mm pitch length corresponds to 75 teeth with a 20 mm tooth pitch.

Conti Synchroflex AT20 GEN III 1500: can GEN III run on standard AT20 discs?

Continental states that the GEN III version can be used on standard timing belt pulleys for the corresponding AT20 profile. However, the pulleys must be in good condition and the drive must be dimensioned for the load you want to utilize.

The most important thing about this size

Conti Synchroflex AT20 GEN III 1500 is the correct size when the drive requires AT20 GEN III, 1500 mm pitch length and 75 teeth. The belt is cast endless in PU with steel cord and must be used with timing belt pulleys that match the profile. Choose the width according to the technical load and always check the design, alignment and pretension before commissioning.