Conti Synchroflex AT3 GEN III 300

Conti Synchroflex AT3 GEN III 300 – dimensionally stable PU timing belt for positioning and transmission

The Conti Synchroflex AT3 GEN III 300 combines a precise AT3 GEN III tooth geometry with a molded polyurethane body and longitudinally stable steel cord tension elements. The product has 100 teeth and a 300 mm pitch length, which corresponds to a tooth pitch of 3 mm. The belt is used in synchronous drives where uniform movement and reproducible position are more important than the elasticity normally associated with a conventional V-belt or flat belt. The GEN III version is the reinforced high-performance construction with red high-performance polyurethane and a denser, two-filament steel cord. It should therefore be treated as a separate product series and not as the usual standard version.

The most important product data

• Pitch length: 300 mm
• Number of teeth: 100
• Tooth profile: AT3 GEN III
• Tooth pitch: 3 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.

How tooth geometry works

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.

Belt construction

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 specific product version

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.

Which drives is the product compatible with?

The application examples in the catalogue include small power drives, handling equipment, compact positioning axes and light synchronous feeds. This shows that the profile can be used in both power transmission and motion control. However, the specific belt must only be finally selected when the machine's torque, speed, center distance and pulley geometry are known. When simply replacing a spare part, the safest method is usually to copy the documented profile, length, design and width.

Selection of discs for the profile

A belt with the correct length can still function poorly if the pulleys have the wrong profile, are worn or are misaligned. Therefore, check the tooth grooves, flanges, shaft alignment and the number of teeth on the pulleys. For AT3 GEN III, the nominal tooth pitch is 3 mm. The fixed tooth mesh makes the gear ratio reproducible, but only when the belt has sufficient wrap and does not run with constant side pressure.

Splice, alignment and pre-tensioning

The belt must be able to be placed on the pulleys without force. If it can only be mounted by forcing it over a flange, the center distance or mounting procedure is incorrect. The pulley shafts must be aligned and the flanges must be smooth and undamaged. In the case of multi-shaft or counter-bent drives, the diameter and position of the rollers must be assessed separately. Correct pretensioning reduces the risk of tooth skipping without unnecessarily loading the bearings.

From basic width to desired width

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 6 mm. Integer widths from 6 to 50 mm can be selected on this product page. The original supplier widths for this length are 6, 8, 10, 12, 16, 20, 25, 32 and 50 mm. Other intermediate sizes are offered as cut-to-size versions 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.

What does belt wear indicate?

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.

Operating conditions of PU timing belt

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.

How to identify the correct replacement belt

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.

Technical questions about the product

Conti Synchroflex AT3 GEN III 300: can the width be measured with a regular caliper?

Yes, the belt width can usually be measured directly on the flat back or between clean, undamaged edges. However, the width is only one part of the identification. The profile, pitch length, number of teeth and any DL or GEN III version must also be correct.

Conti Synchroflex AT3 GEN III 300: does this PU timing belt need to be lubricated?

No. The timing belt is designed for lubrication-free operation. Oil or grease should not be added to reduce noise as this may mask an alignment, pretension or worn pulley problem. Instead, keep the tooth mesh clean and check the cause of any abnormal noise.

Conti Synchroflex AT3 GEN III 300: can GEN III run on standard AT3 discs?

Continental states that the GEN III version can be used on standard timing belt pulleys for the corresponding AT3 profile. However, the pulleys must be in good condition and the drive must be dimensioned for the load you want to utilize.

Conti Synchroflex AT3 GEN III 300: 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 AT3 GEN III 300: 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 AT3 GEN III 300: can the belt be reversed on the pulleys?

The standard version is single-sided with teeth on the inside and a smooth back. It must run with the teeth in the corresponding tooth grooves; the back is not an alternative tooth side.

How many teeth does the Conti Synchroflex AT3 GEN III 300 have?

The belt has 100 teeth. The number of teeth is calculated by dividing the pitch length of 300 mm by the tooth pitch of 3 mm. The result is 100, and this number can be used as an additional check when identifying an existing belt. A different number of teeth means a different pitch length.

Conclusion

The product brings together the specified AT3 GEN III profile and length on one side, so that the appropriate width can be selected without creating a separate item for each cut. The main technical data is 300 mm pitch length and 100 teeth. If in doubt about load or pulley compatibility, the drive should be calculated before ordering the belt.