PU timing belt AT3 150 - Conti® Synchroflex

Conti Synchroflex AT3 150 – durable PU timing belt with stable tooth pitch

The Conti Synchroflex AT3 150 combines a precise AT3 tooth geometry with a molded polyurethane body and longitudinally stable steel cord tension elements. The product has 50 teeth and a 150 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. 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.

The most important product data

• Pitch length: 150 mm
• Number of teeth: 50
• Tooth profile: AT3
• Tooth pitch: 3 mm
• Material: cast polyurethane with steel cord
• Brand: Conti Synchroflex

The technical data below describes the part of the product that does not change when a different belt width is selected. Pitch length, tooth pitch and number of teeth remain identical for all width choices. However, the width affects the available belt cross-section width and the price calculated on the product page. Correct sizing must always take into account torque, speed, number of teeth in mesh, pulley diameters, service factor and any counter-bending.

How tooth geometry works

The metric AT geometry has trapezoidal teeth with a larger tooth volume than the standard T profile. The purpose is to distribute the load advantageously in the tooth mesh and achieve higher tooth strength without making the drive unnecessarily large. The profile requires suitable AT timing belt pulleys with the same pitch; a visual similarity to other profiles is not evidence of compatibility.

Materials and endless manufacturing

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.

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.

Typical applications and sizing

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.

The belt width is selected on the product page

This product line has been created with 8 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 8 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.

Gear ratio, enclosure and tooth contact

A belt of 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, 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.

Pre-tensioning and disc alignment

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.

Compare with the existing 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.

Checking teeth, back and edges

Uniform light polishing of the tooth flanks may be normal, but localised spalling, ctiming baring or severe wear should be investigated. Wear on one edge often indicates misalignment or persistent flange contact. Damage to tooth tips may be due to incorrect profile, foreign bodies or inadequate engagement. If cord becomes visible or the belt has a sharp break, it should not continue in service without assessment.

Operating conditions of PU timing belt

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.

Technical questions about the product

How many teeth does the Conti Synchroflex AT3 150 have?

The belt has 50 teeth. The number of teeth is calculated by dividing the pitch length of 150 mm by the tooth pitch of 3 mm. The result is 50, 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 AT3 150: 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 150: 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 150: 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, 50 teeth at 3 mm pitch gives a length of 150 mm. It is a simple check that often reveals faults that are not visible by a quick comparison of two loose belts.

Conti Synchroflex AT3 150: 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 AT3 150: how to check if the length is correct?

Count the teeth and check the pitch. 50 teeth times 3 mm gives 150 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 AT3 150: how does preload affect operation?

Correct pretension keeps the teeth in stable engagement and reduces the risk of tooth jump. Too low a tension can cause impact and jump under load, while too high a tension increases the load on the cord, pulleys and bearings. The correct value must be determined based on the drive's dimensioning.

Conti Synchroflex AT3 150: 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.

Summary

In summary, this is a Conti Synchroflex PU timing belt with a fixed geometry of 3 mm pitch, 50 teeth and 150 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.