Conti Synchroflex AT20 GEN III 1700

Conti Synchroflex AT20 GEN III 1700 – endless timing belt for precise industrial drives

This AT20 GEN III timing belt is specified with a pitch length of 1700 mm and 85 teeth. The ratio between length and number of teeth is fixed: 1700 mm divided by 20 mm gives exactly 85 teeth. The Conti Synchroflex AT20 GEN III 1700 is supplied as a cast, endless PU belt, so that there is no weld joint in the finished ring. The design is developed for synchronous operation and precise machine movements. The GEN III version is the reinforced high-performance design 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 regular standard version.

The most important product data

• Pitch length: 1700 mm
• Number of teeth: 85
• Tooth profile: AT20 GEN III
• Tooth pitch: 20 mm
• Material: cast polyurethane with steel cord
• Brand: Conti Synchroflex

The list gathers the information normally used to identify a timing belt: nominal length, number of teeth, profile, material and make. It is important to read all the information together. Two belts can have the same pitch length but be incompatible if the tooth profile or tooth pitch is different. Conversely, a different width does not change the number of teeth as long as the profile and pitch length are the same.

What characterizes the AT20 GEN III profile?

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.

How the Conti Synchroflex belt is constructed

With the cast manufacturing method, the finished belt becomes an exact copy of a precision-machined shape. This is a major reason for the uniform tooth pitch and reproducible length. The steel cord is integrated into the polyurethane and contributes to position and angular precision. The design is suitable for synchronous drives, where a conventional elastic friction belt does not provide the desired repeatability.

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.

Profile and length must match

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.

Relevant machine tasks

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.

Choosing belt 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 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.

Gear ratio, enclosure and tooth contact

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 the AT20 GEN III, the nominal tooth pitch is 20 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.

How to avoid unnecessary wear and tear

The timing belt pulleys must be parallel and in the same plane. Even minor misalignments can cause the belt to move towards a flange and cause edge or cord damage. The belt should be installed without being twisted, sharply bent or pressed over a flange with a tool. The center distance is adjusted to achieve the calculated preload. Too high a tension increases the bearing and cord load, while too low a tension can cause tooth jumps at load peaks.

Environmental impact and ongoing monitoring

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.

Wear patterns and troubleshooting

A properly running timing belt should move smoothly without continuous contact against one flange. Regularly check the teeth for deformation, the back for ctiming bars and the edges for frayed areas. Abnormal noise or heat can be an early sign of incorrect tension or pulley failure. A systematic check of pulleys and belt is more effective than trying to hide symptoms with lubricant.

Answers to typical questions

Conti Synchroflex AT20 GEN III 1700: how to check if the length is correct?

Count the teeth and check the pitch. 85 teeth times 20 mm gives 1700 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.

Conti Synchroflex AT20 GEN III 1700: what does the steel cord mean for the function of the belt?

The steel cord tension members absorb the longitudinal tensile load and provide high longitudinal stiffness. This helps maintain pitch and position during operation. The cord must not be kinked, exposed or damaged during installation, as local damage can weaken the belt.

How many teeth does the Conti Synchroflex AT20 GEN III 1700 have?

The belt has 85 teeth. The number of teeth is calculated by dividing the pitch length of 1700 mm by the tooth pitch of 20 mm. The result is 85, 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.

Conti Synchroflex AT20 GEN III 1700: 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.

Conti Synchroflex AT20 GEN III 1700: why is 16 mm chosen as the basic width?

16 mm is the width of the supplier item whose SKU is used as the main product's stock reference. Other widths are handled as choices under the same product because they are cut from the same type of timing belt sleeve. The base width also determines the percentage-based pricing in the webshop.

Conti Synchroflex AT20 GEN III 1700: 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, 85 teeth at 20 mm pitch gives a length of 1700 mm. It is a simple check that often reveals faults that are not visible by a quick comparison of two loose belts.

Conti Synchroflex AT20 GEN III 1700: 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.

The product in brief

In summary, this is a Conti Synchroflex PU timing belt with a fixed geometry of 20 mm pitch, 85 teeth and 1700 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.