PU timing belt AT3 1011 - Conti® Synchroflex

Conti Synchroflex AT3 1011 – dimensionally stable PU timing belt for positioning and transmission

With 337 teeth distributed over a pitch length of 1011 mm, the Conti Synchroflex AT3 1011 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 3 mm and the tooth profile must match the profile of the pulleys exactly. It is not sufficient for another belt to have approximately the same length or width. This is the standard version in the specified profile. It must not be confused with a possible GEN III version or a double-sided DL belt with the same pitch length.

Dimensions, profile and number of teeth

• Pitch length: 1011 mm
• Number of teeth: 337
• Tooth profile: AT3
• 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.

Why the correct profile is crucial

In a synchronous belt drive, the movement is transmitted through the tooth flanks. The geometry of the AT profile is therefore crucial for both load distribution, noise level and position accuracy. A correct AT pulley supports the teeth according to the profile to which they are cast. If the pulley's tooth shape or pitch deviates, the load can be concentrated at a few pu and cause abnormal wear, even though the belt can apparently be mounted.

Cast polyurethane and steel cord

Conti Synchroflex is manufactured by casting, where the polyurethane is precisely shaped to the tool's tooth geometry around the embedded steel cord tension elements. The casting process provides high pitch accuracy over the entire circumference of the belt and a strong connection between PU and cord. The finished timing belt is endless and therefore has no welded joints. The polyurethane provides a wear-resistant tooth and back surface, while the steel cord takes the longitudinal tensile load.

The execution must be correctly identified

The standard version is selected when the supplier's article data does not specify GEN III or DL. This is an important product distinction, because different versions can share both profile and length. Therefore, on this product page, it is the standard version that is described. The belt width can be selected, but the basic construction and tooth geometry are not changed.

Areas of application

The profile series is used in practice for tasks such as small power drives, handling equipment, compact positioning axes and light synchronous feeds. Common to these machines is the need for a fixed transmission ratio and controlled tooth meshing. A timing belt can transmit both force and position, but the capacity cannot be assessed based on length alone. Width, profile version, wrap angle and load cycle are among the data that must be included in the selection.

Temperature, media and service

The standard material is specified for ambient temperatures from -30 °C to +80 °C. Applications close to the limits, especially below -10 °C or above +50 °C, may require special sizing. The service life is not only affected by the material, but also by load peaks, bending, pulley size, alignment and environment. Keep the drive clean and do not remove deposits with sharp tools that could damage the teeth. If the belt operates in chemically exposed areas, food environments, clean rooms or at extreme temperatures, a suitable special design should be considered.

How the width variants work

This product line has been created with 6 mm as the base width because this is the width of the selected item and thus the SKU used for inventory control. Integer widths from 6 to 50 mm can be selected on this product page. The widths that appear as standard widths in the supplier data are marked separately in the options. The price surcharge is calculated as a percentage of the base width: doubling the width results in a surcharge of 100%. The technically necessary width should be selected according to the load and not only according to the price.

Timing belt pulleys and transmission ratios

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 3 mm pitch and the correct AT3 tooth shape, and check that the flanges do not damage the belt edge.

Practical advice for installation

Proper installation begins with clean, undamaged pulleys with the correct profile. Teeth and grooves should be checked for deposits, bars and wear before the new belt is fitted. The pretension should be based on the drive's calculation and should not be selected based on a random hand feel. After the initial run-in, it is a good idea to check grooveing, noise, temperature and whether the belt runs centrally.

Wear patterns and troubleshooting

Troubleshooting should start with pu location of the damage. Edge wear is typically associated with grooveing and alignment, while tooth skipping can be associated with too low tension, load peaks or too few teeth in mesh. Ctiming bars on the back can be caused by too small rollers, back bending or environmental influences. Do not simply replace the belt without also finding the mechanical cause.

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 AT3 1011: what is the difference between AT3 and a GEN III belt?

This product is the standard version. GEN III is a separate reinforced series with red high-performance PU and denser, two-filament steel cord. The same profile and length therefore do not mean that the products are identical.

Conti Synchroflex AT3 1011: can this belt be used at high speeds?

The Conti Synchroflex series is designed for precise and fast synchronous drives, but the permissible speed depends on the profile, pulley diameter, belt width, load and peripheral speed. A high speed must therefore not be approved based on the product name alone; the drive must be calculated.

Conti Synchroflex AT3 1011: 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 1011: 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.

Is the Conti Synchroflex AT3 1011 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 AT3 1011: 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 1011 mm and the same number of teeth of 337. 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 AT3 1011: what is the difference between tooth pitch and pitch length?

The tooth pitch is the distance from one tooth to the next and is 3 mm for this profile. The pitch length is the entire nominal circumference in the cord line and is 1011 mm. When the pitch length is divided by the tooth pitch, the belt has 337 teeth.

Conti Synchroflex AT3 1011: can the belt be installed by pressing it over the pulley flange?

This should be avoided. The belt should be installed by adjusting the center distance or following the correct installation procedure for the machine. Forcing it over a flange can damage the cord pullers, teeth or belt edge. After installation, the pulleys must be parallel and the pretension must be correct.

Summary

In summary, this is a Conti Synchroflex PU timing belt with a fixed geometry of 3 mm pitch, 337 teeth and 1011 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.