PU timing belt AT3 201 - Conti® Synchroflex

Conti Synchroflex AT3 201 – precise PU timing belt for synchronous power transmission

Conti Synchroflex AT3 201 is an endless, cast polyurethane timing belt with 67 teeth, 3 mm tooth pitch and a pitch length of 201 mm. It is intended for synchronous power transmission, where the driving and driven shafts must follow a fixed tooth ratio without the slippage known from friction-based belt drives. The pitch length is the nominal length measurement in the belt's cord line and is therefore the measurement that must be compared with the existing belt, the machine's spare parts data and the installed timing belt pulleys. 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.

Technical information for this timing belt

• Pitch length: 201 mm
• Number of teeth: 67
• Tooth profile: AT3
• Tooth pitch: 3 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.

Why the correct profile is crucial

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.

PU body and longitudinally stable traction elements

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.

The construction behind this variant

The product is the regular Conti Synchroflex standard version in the specified profile. Standard and GEN III may have the same pitch length and number of teeth, but they are different product series with different material construction and capacity data. The same applies to a DL belt, which has teeth on both sides. When reordering, the entire profile designation should therefore be checked, not just the length.

Relevant machine tasks

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.

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.

Timing belt pulleys and transmission ratios

The pulleys and belt should be considered as a single tooth engagement. Correct AT3 geometry ensures that the load is distributed over the tooth flanks rather than concentrated on tooth tips or edges. The drive ratio is selected by the number of teeth on the pulleys, while the belt's 67 teeth and 201 mm pitch length determine the required combination of pulleys and center distance. When changing the drive, the geometry should be calculated.

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.

Profile and length must match

It is not enough to compare the total circumference of a belt. The correct replacement must have the same pitch, tooth profile and number of teeth as the existing drive. The width must match the pulleys and the required capacity, and a DL or GEN III version must be identified separately. If in doubt, pictures of the marking, tooth profile and pulleys can be used as a supplement, but a documented spare part designation is best.

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.

Operating environment and maintenance

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.

Questions and answers about this timing belt

Conti Synchroflex AT3 201: 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, 67 teeth at 3 mm pitch gives a length of 201 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 201: 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 201 mm and the same number of teeth of 67. 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 201: why is 6 mm chosen as the basic width?

6 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 AT3 201: 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.

Conti Synchroflex AT3 201: 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.

Is the Conti Synchroflex AT3 201 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 201: 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.

Brief summary

Conti Synchroflex AT3 201 is the correct size when the drive requires AT3, 201 mm pitch length and 67 teeth. The belt is cast endless in PU with steel cord and must be used with timing belt pulleys that match the profile. Choose the width according to the technical load and always check the design, alignment and pretension before commissioning.