Double-Sided Timing Belts
Double-sided timing belts have teeth on both the inside and outside surfaces, allowing the belt to engage sprockets on both sides. This enables serpentine drive layouts, counter-rotating shaft configurations, and multi-sprocket arrangements where both sides of the belt must mesh with toothed sprockets. Standard single-sided timing belts have teeth on one side and a flat back, which can only drive sprockets on the toothed side.
Double-sided timing belts are available in neoprene and polyurethane construction across the most commonly used profiles. They are a specialty product with longer lead times and higher costs than single-sided belts of the same profile and size. Texas Belting stocks select double-sided sizes and can source any double-sided timing belt from major manufacturers.
Construction: Teeth on both sides of the belt (inside and outside)
Designation: Typically marked with a "D" prefix or suffix (for example, D5M, D8M, DXL, DL, DH)
Available profiles: HTD (D3M, D5M, D8M, D14M), trapezoidal (DXL, DL, DH), GT, T-profile
Materials: Neoprene with fiberglass cord (standard); urethane with steel cord (specialty)
Format: Closed-loop only
How Double-Sided Timing Belts Work
On a standard single-sided timing belt, the toothed side engages the sprockets while the flat back side runs over flat idler pulleys (if used). On a double-sided belt, both surfaces have teeth. This allows the belt to engage toothed sprockets on the inside of the belt loop and on the outside, enabling more complex drive configurations:
- Serpentine drives: The belt wraps around multiple sprockets in an S-pattern, alternating between inside and outside tooth engagement. This allows a single belt to drive multiple shafts from a single motor.
- Counter-rotating drives: Two shafts that need to rotate in opposite directions can be driven by a single double-sided belt, with one shaft engaging the inside teeth and the other engaging the outside teeth.
- Complex multi-sprocket layouts: Equipment designs that require the belt path to wrap both inside and outside of multiple sprockets in a single loop.
Double-Sided Part Number Format
Double-sided timing belts are designated by adding a "D" prefix or suffix to the standard part number. The specific format varies by manufacturer and profile.
| Example Part Number | Profile | Pitch Length | Width | Notes |
|---|---|---|---|---|
| D600-5M-15 | D5M (HTD double-sided) | 600mm | 15mm | "D" prefix indicates double-sided |
| D1120-8M-20 | D8M (HTD double-sided) | 1120mm | 20mm | "D" prefix indicates double-sided |
| 300DL075 | DL (trapezoidal double-sided) | 30.0" | 3/4" | "D" before profile code |
| 450DH200 | DH (trapezoidal double-sided) | 45.0" | 2" | "D" before profile code |
Not sure how to read your double-sided part number? Call 888-203-2358 or send us the number and we will identify it.
Profiles Available in Double-Sided
| Profile Family | Double-Sided Designation | Pitches Available | Material |
|---|---|---|---|
| HTD | D3M, D5M, D8M, D14M | 3mm, 5mm, 8mm, 14mm | Neoprene (standard) |
| GT / GT3 | D-GT3 | 3M, 5M, 8M | Neoprene |
| Trapezoidal (ANSI) | DXL, DL, DH | XL, L, H | Neoprene |
| T-Profile | DT5, DT10 | 5mm, 10mm | Neoprene or urethane |
| AT-Profile | DAT5, DAT10 | 5mm, 10mm | Urethane |
D5M and D8M (HTD double-sided) are the most commonly stocked double-sided sizes. DL and DH are the most common ANSI double-sided profiles. Larger and less common sizes may require special order. Contact Texas Belting for current stock availability.
Double-Sided vs. Single-Sided: Key Differences
| Factor | Single-Sided (Standard) | Double-Sided |
|---|---|---|
| Teeth | One side only (inside) | Both sides (inside and outside) |
| Back surface | Flat (can run over flat idlers) | Toothed (must engage toothed sprockets on both sides) |
| Belt thickness | Standard | Thicker (two tooth layers) |
| Minimum pulley size | Standard for profile | Larger minimum (thicker belt bends less easily) |
| Cost | Standard | Higher (specialty manufacturing) |
| Availability | Broadly stocked | Limited stock, many sizes made to order |
| Drive layouts | Standard two-sprocket or multi-sprocket (inside mesh only) | Serpentine, counter-rotating, complex multi-sprocket |
Common Double-Sided Timing Belt Applications
| Application | Why Double-Sided | Typical Profile |
|---|---|---|
| Textile machinery | Multiple rollers driven from a single belt, alternating wrap direction | D5M, DL, DT5 |
| Packaging equipment | Counter-rotating seal bars, multiple driven stations | D5M, D8M, DL |
| Printing and converting | Multiple rollers at precise synchronization, serpentine layout | D5M, DL, DH |
| Paper handling | Multiple feed rollers driven in alternating directions | DXL, DL, D5M |
| Woodworking machinery | Multiple spindle drives with counter-rotating cutters | D8M, DH |
| Material handling conveyors | Multiple conveyor rollers driven from one belt in serpentine | D8M, D14M, DH |
| Automotive and engine accessories | Serpentine accessory drives with multiple pulleys | D5M, D8M |
| Medical and laboratory equipment | Compact multi-axis drives requiring counter-rotation | DXL, D3M, D5M |
Double-Sided Timing Belt Brands We Carry
| Brand | Double-Sided Products | Notes |
|---|---|---|
| Gates | PowerGrip D-HTD, D-GT3, D-trapezoidal | Broadest double-sided range in neoprene |
| Continental / ContiTech | Synchroforce double-sided HTD, T-profile | OEM and replacement |
| Bando | Bando double-sided HTD, trapezoidal | Japanese OEM spec |
| Diesel Belting | Diesel double-sided HTD | Cost-effective replacement for common D-HTD sizes |
| Megadyne | Megalinear double-sided | Neoprene and urethane double-sided options |
Double-Sided Timing Belt FAQs
Need Double-Sided Timing Belts?
Double-sided belts are specialty items. Send us your part number or drive layout for availability, lead time, and pricing.
