Conti Synchroflex T10 1390

Conti Synchroflex T10 1390 – dimensionally stable timing belt for positioning and power transmission

When a timing belt needs to be replaced correctly, the profile, pitch length and number of teeth are the first data that must be correct. The Conti Synchroflex T10 1390 has a T10 profile, 10 mm tooth pitch, 1390 mm pitch length and 139 teeth. This makes the product unique in terms of length and profile, while the belt width is selected separately on the product page. The belt is manufactured as an endless Conti Synchroflex PU timing belt with steel cord. 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.

Product data and fixed targets

• Pitch length: 1390 mm
• Number of teeth: 139
• Tooth profile: T10
• Tooth pitch: 10 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

The T-profile is the classic metric timing belt profile with trapezoidal teeth and is described as a standard profile according to DIN 7721. It is used for general synchronous drives, positioning tasks and solutions with significant bending. The simple and proven geometry of the profile makes it widely used, but it still needs to be matched with a T-disc with the same tooth pitch. AT, HTD and other profiles are not automatically interchangeable.

How the Conti Synchroflex belt is constructed

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 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.

Typical applications and sizing

The application examples in the catalogue include machine tools, main and auxiliary drives, textile machines and printing machines. 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.

Selection of discs for the profile

The pulleys and belt should be considered as a single tooth engagement. Correct T10 geometry ensures that the load is distributed over the tooth flanks instead of being concentrated on tooth tips or edges. The drive ratio is selected by the number of teeth on the pulleys, while the belt's 139 teeth and 1390 mm pitch length determine the required combination of pulleys and center distance. When changing the drive, the geometry should be calculated.

Correct splice in the timing belt tensioner

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.

From basic width to desired width

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.

Signs of improper operation

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.

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.

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.

Technical questions about the product

Conti Synchroflex T10 1390: what temperature can the belt work at?

The standard version is specified for ambient temperatures from -30 °C to +80 °C. At temperatures below -10 °C or above +50 °C, adapted sizing may be required.

Conti Synchroflex T10 1390: can T10 be used on a different tooth profile with the same pitch?

No, not without documented compatibility. The 10 mm tooth pitch describes the distance between the teeth, but the shape and clearance of the tooth flanks may differ. The belt must be used with pulleys manufactured for the T10 profile. Visual similarity is not sufficient documentation.

Conti Synchroflex T10 1390: 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 T10 1390: is the polyurethane oil and chemical resistant?

The standard PU is described as resistant to simple oils, grease and petrol as well as certain acids and bases. This does not mean universal chemical resistance. In the case of continuous contact, high concentrations or cleaning agents, the specific liquid, temperature and exposure time should be assessed.

Conti Synchroflex T10 1390: are the standard widths the only possible widths?

The documented supplier widths for this size include 6, 8, 10, 12, 16, 20, 25, 32 and 50 mm. The product page may also show intermediate sizes as cut widths when they are within the allowed range. This does not change the tooth profile or length, but the price is calculated based on the base width.

Conti Synchroflex T10 1390: 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.

Is the Conti Synchroflex T10 1390 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 T10 1390: can the belt be turned upside down on the pulleys?

The standard version is single-sided with teeth on the inside and a smooth back. It must run with the teeth in the corresponding tooth grooves; the back is not an alternative tooth side.

Conclusion

In summary, this is a Conti Synchroflex PU timing belt with a fixed geometry of 10 mm pitch, 139 teeth and 1390 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.