AT-Series Polyurethane Timing Belts
AT-Series Polyurethane Timing Belts
AT-Series timing belts are high-performance polyurethane synchronous belts with a modified curvilinear tooth profile that delivers up to 30% higher power capacity than equivalent T-Series belts at the same pitch. The arc-shaped tooth geometry provides smoother engagement, lower backlash, reduced vibration, and significantly better resistance to tooth shear under heavy or shock loads.
Texas Belting stocks AT-Series polyurethane timing belts in AT3, AT5, AT10, and AT20 pitches. All pitches are available in open-ended rolls, welded endless loops, and truly endless molded configurations with steel cord or aramid tension members. Optional backings, tooth coatings, and machined modifications are available for conveying, linear motion, and specialty applications.
- Pitches: AT3, AT5, AT10, AT20
- Tooth profile: modified curvilinear (arc-shaped)
- Up to 30% higher power than T-Series at same pitch
- Widths: 6mm to 150mm depending on pitch
- Near-zero backlash with SE and 0-gap pulleys
- Configurations: open-ended, welded, truly endless
- Temperature range: -30°C to +80°C (+100°C with Gen III)
- FDA food-grade and cleanroom options available
AT3: 3mm Pitch
Compact, high-performance belts for precision drives, small servo systems, and instrumentation applications where AT-profile advantages are needed in a small package.
| Configuration | Available Widths (mm) | Details |
|---|---|---|
| Open-Ended | 6, 10, 16, 25 | Sold per meter |
| Welded | 6, 10, 16, 25 | Custom endless lengths |
| Truly Endless | 6, 10, 16, 25 | Standard lengths: 150 to 2,100mm |
AT5: 5mm Pitch
The most popular AT-Series pitch for industrial automation. AT5 belts provide excellent performance for servo drives, indexing systems, and medium-duty conveying applications.
| Configuration | Available Widths (mm) | Details |
|---|---|---|
| Open-Ended | 16, 25, 32, 50, 75, 100 | Sold per meter |
| Welded | 16, 25, 32, 50, 75, 100 | Custom endless lengths |
| Truly Endless | 16, 25, 32, 50, 75, 100 | Standard lengths: 210 to 4,500mm |
AT10: 10mm Pitch
The workhorse of heavy-duty automation. AT10 belts handle high torque loads with precision, making them the standard choice for large gantry systems, heavy conveying, and machine tool drives.
| Configuration | Available Widths (mm) | Details |
|---|---|---|
| Open-Ended | 25, 32, 50, 75, 100, 150 | Sold per meter |
| Welded | 25, 32, 50, 75, 100, 150 | Custom endless lengths |
| Truly Endless | 25, 32, 50, 75, 100, 150 | Standard lengths: 370 to 4,500mm |
AT20: 20mm Pitch
Maximum power capacity for the most demanding industrial drives. AT20 belts are specified for heavy machinery, large-format CNC routers, and high-load material handling systems.
| Configuration | Available Widths (mm) | Details |
|---|---|---|
| Open-Ended | 25, 32, 50, 75, 100, 150 | Sold per meter |
| Welded | 25, 32, 50, 75, 100, 150 | Custom endless lengths |
| Truly Endless | 25, 32, 50, 75, 100, 150 | Standard lengths: 600 to 4,500mm |
AT-Series Technical Specifications
The table below lists the dimensional and pulley specifications for each AT-Series pitch. For complete engineering data including tensile strength ratings and allowable tooth loads, see the timing belt specifications reference.
| Pitch | Belt Height (mm) | Tooth Height (mm) | Min. Pulley Teeth | Min. Pulley Teeth (Back Bend) |
|---|---|---|---|---|
| AT3 | 2.4 | 1.2 | 15 | 25 |
| AT5 | 3.6 | 1.8 | 15 | 20 |
| AT10 | 6.0 | 3.4 | 15 | 25 |
| AT20 | 10.0 | 6.2 | 18 | 25 |
Why Upgrade from T-Series to AT-Series
The AT-Series was developed as a direct performance upgrade to the T-Series trapezoidal profile. Both use the same pitch dimensions, so center distances and belt lengths remain the same when upgrading. The key differences are in the tooth geometry and the resulting performance gains.
| Property | T-Series | AT-Series |
|---|---|---|
| Tooth profile | Trapezoidal | Modified curvilinear (arc) |
| Power capacity | Baseline | Up to 30% higher at same pitch |
| Backlash | Standard clearance | Reduced; near-zero with SE/0-gap pulleys |
| Tooth shear resistance | Standard | Significantly improved |
| Vibration and noise | Standard | Reduced (smoother tooth engagement) |
| Pulley compatibility | T-profile pulleys only | AT-profile pulleys only |
Related AT-Profile Belt Series
The AT tooth profile is shared across several specialized belt series, each optimized for a specific class of application:
| Series | Optimized For | Key Advantage |
|---|---|---|
| ATL-Series | Linear positioning | Tighter pitch tolerances for maximum positioning accuracy |
| ATP-Series | Heavy-duty power transmission | Reinforced construction for the highest torque loads |
| ATS15 | High-torque symmetric drives | 15mm symmetric tooth for bidirectional heavy loads |
| ATN Convertible | Configurable conveying | Snap-in reconfigurable profiles for flexible packaging lines |
| Move-Series | High-speed motion control | Optimized for high acceleration and dynamic positioning |
Common Applications
AT-Series belts are the preferred choice for applications where precision, high power density, and reliability under demanding conditions are required. Typical equipment includes servo-driven positioning systems, CNC machines and machine tools, packaging machinery, injection molding machines, linear gantry systems, delta and SCARA robots, automated assembly equipment, and semiconductor handling systems.
For conveying applications, AT-Series belts can be fitted with welded or snap-in profiles and backing materials to handle product transport, indexing, and positioning tasks.
Frequently Asked Questions
Choose AT-Series when you need higher power capacity, reduced backlash, or better resistance to shock loads. The modified curvilinear tooth profile engages more gradually than the T-Series trapezoidal profile, providing smoother operation, less vibration, and up to 30% more power at the same pitch. AT belts are the standard choice for servo-driven systems, CNC machines, robotics, and any application where positioning accuracy and reliability are critical.
AT-Series belts cannot be used on T-Series pulleys because the tooth profiles are different. Upgrading from T-Series to AT-Series requires replacing both belts and pulleys. However, both series use the same pitch dimensions, so center distances and belt lengths remain the same. Contact Texas Belting at 888-203-2358 for help planning a T-to-AT upgrade.
Zero backlash pulleys (designated "0") have a tighter tooth gap that virtually eliminates play between the belt and pulley. This provides the highest positioning accuracy for precision linear drives and is available for AT-Series pulleys in most tooth counts. SE (special engagement) pulleys offer a similar reduced-backlash option. See the high precision pulleys page for details.
AT10 (10mm pitch) is the most widely specified AT-Series belt for industrial automation. It provides high power capacity with moderate pulley sizes and is available in the widest range of configurations, materials, and width options (up to 150mm). AT5 is the most popular choice for smaller, precision drives where compact pulleys are needed.
Standard AT-Series belts operate from -30°C to +80°C. The Redflex GEN III compound extends the continuous upper limit to +100°C, with short-term peak temperatures up to +120°C tolerable depending on load conditions. Below -30°C, special low-temperature formulations may be required.
For two-pulley drives, belt pitch length equals 2 times the center distance plus pi times the sum of both pulley pitch diameters divided by 2, plus the difference of the diameters squared divided by 4 times the center distance. Texas Belting offers free drive design assistance to help you select the optimal belt length, width, and pitch for your application. Call 888-203-2358 or submit your drive details through the quote request form.
Both use the same AT tooth profile, but ATL-Series belts are specifically optimized for linear positioning applications. ATL belts have tighter pitch tolerances and are manufactured to minimize cumulative pitch error over long belt lengths. For rotary power transmission, standard AT-Series belts are the correct choice. For precision linear gantry systems, ATL belts deliver the best positioning accuracy.
Yes. AT-Series belts are available in FDA 21 CFR 177.2600 compliant polyurethane with sealed stainless steel tension members. These belts are suitable for direct food contact and washdown environments in food processing and pharmaceutical applications. See the food-grade polyurethane timing belts page for full details.
Need AT-Series Timing Belts?
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