Conti Synchroflex AT5 GEN III 340

Conti Synchroflex AT5 GEN III 340 – durable PU timing belt with stable tooth pitch

Conti Synchroflex AT5 GEN III 340 combines a precise AT5 GEN III tooth geometry with a molded polyurethane body and longitudinally stable steel cord tension elements. The product has 68 teeth and a 340 mm pitch length, which corresponds to a tooth pitch of 5 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 structure. It should therefore be treated as a separate product series and not as the usual standard version.

Dimensions, profile and number of teeth

• Pitch length: 340 mm
• Number of teeth: 68
• Tooth profile: AT5 GEN III
• Tooth pitch: 5 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.

Cast polyurethane and steel cord

The belt body consists of wear-resistant polyurethane, which encloses high-strength steel cord. The materials each have their own function: PU forms the teeth and protects the belt against mechanical wear, while the cord tensioning elements provide high longitudinal stiffness and limit post-elongation. Continental describes the design as maintenance-friendly and lubrication-free. This does not mean that the drive can be ignored; pulleys, alignment and pretension should still be checked.

Standard, GEN III or DL ​​– this 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.

Where is this profile used?

The application examples in the catalogue include machine tools, pu , textile machines and positioning and conveying systems. 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.

Operating environment and maintenance

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 cast PU belt is maintenance-friendly and does not require lubricant. Regular visual inspection is still relevant: look for ctiming bars, frayed edges, shiny tooth flanks, foreign body impressions and abnormal side contact. Sudden changes in noise or grooveing can be signs of misalignment, too low tension or worn pulleys.

Width selection and price calculation

The basic price applies to 6 mm, and the other widths are calculated with the same percentage logic as the existing PU timing belts in the webshop. Integer widths from 6 to 50 mm can be selected on this product page. A width of twice the basic width therefore costs 100% more, while a width of one and a half times the basic width gives approximately 50% extra. This price rule is a webshop calculation; it does not replace a technical dimensioning of the belt's load-bearing capacity.

Selection of discs for the profile

The tooth profile of the timing belt pulleys must correspond to the AT5 GEN III of the belt, and their pitch must be 5 mm. The transmission ratio is determined by the ratio of the number of teeth of the pulleys, not by the width of the belt. A larger pulley usually reduces the bending load, while a very small pulley gives more bending per revolution. The angle of engagement and the number of teeth in mesh must be sufficient for the current load.

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.

Signs of improper operation

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.

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 AT5 GEN III 340: why is the number of teeth important for spare parts?

The number of teeth links the pitch of the profile to the nominal length of the belt. For this size, 68 teeth at 5 mm pitch gives a length of 340 mm. It is a simple check that often reveals faults that are not visible by a quick comparison of two loose belts.

Conti Synchroflex AT5 GEN III 340: can GEN III run on standard AT5 discs?

Continental states that the GEN III version can be used on standard timing belt pulleys for the corresponding AT5 profile. However, the pulleys must be in good condition and the drive must be dimensioned for the load you want to utilize.

Conti Synchroflex AT5 GEN III 340: when should the timing belt pulleys be replaced?

Pulleys should be evaluated if the tooth grooves are worn, sharp, crooked or damaged. A new belt on worn pulleys may have poor load distribution and short life. Also check flanges for bars and side contact and the grooves for foreign objects.

Is the Conti Synchroflex AT5 GEN III 340 welded?

No. The Conti Synchroflex series is manufactured as cast, endless timing belts. The belt therefore does not have a welded joint around the circumference. The cast process provides a uniform tooth pitch around the entire belt and a strong bond between the polyurethane and the cast steel cord tension elements.

Conti Synchroflex AT5 GEN III 340: 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 AT5 GEN III 340: what happens if the discs are not aligned?

Misalignment can cause the belt to wander towards a flange, causing edge pressure, heat and wear damage. It can also affect tooth engagement and reduce service life. Check both the parallelism of the shafts and the alignment of the pulleys.

Conti Synchroflex AT5 GEN III 340: how best to store a spare timing belt?

Store the belt in a dry, clean place away from direct sunlight, ozone, strong heat or chemical fumes. It should be free from sharp bends and without heavy loads on top. Avoid hanging a small belt over a sharp hook as this can cause local deformation.

Conti Synchroflex AT5 GEN III 340: how to check if the length is correct?

Count the teeth and check the pitch. 68 teeth times 5 mm gives 340 mm pitch length. Then compare the profile and design with the marking or the machine's spare parts list. A measurement around the outside of the belt alone is not accurate enough.

Brief summary

In summary, this is a Conti Synchroflex PU timing belt with a fixed geometry of 5 mm pitch, 68 teeth and 340 mm pitch length. The width is selected separately, but does not change the length or number of teeth. A safe replacement requires that the entire designation and the specific version match the machine documentation.