Skip to content 
Open-ended timing belt has many methods to join as ring shape.This passage mainly introduce some joint ways and its advantages and disadvantages.
Hot Melt Finger Joint
This is a method of melting and fusing together the two ends of the synchronous belt by heating them, which provides extremely high connecting strength and stability for applications in a wide range of loads and speeds.
Procedures:
- Prepare the correct specification of PU timing belt and clean the belt ends
- Use timing belt finger cutter to make finger on two ends of belt and align the belt ends
- Use the belt joint machine to heat the belt ends until melting and press together until the belt cooling
- When the spliced process is finished, trim any excess adhesive from the joint
Advantages:
- High Strength: The vulcanized joint method can provide the joint part same or close strength as other part of timing belt.
- Durability: The durability of vulcanized joint is better than that of mechanical joint, which is suitable for belt long-term continuous operation.
Disadvantages:
- High Cost: Compared with mechanical joint, vulcanized joint has higher cost.
- ComplicateProcess: Professional vulcanization equipment and technical personnel is needed.
Mechanical Joint
Both ends of the timing belt are connected by mechanical elements such as metal buckles, bolts and steel pins, which is often used to quickly install or replace a synchronous belt without disassemble machine.
Advantages:
- Lower Cost: Compared with other joint methods, mechanical joint cost is relative lower.
- Fast Installation: Quick install and replace the timing belt no need tools
Disadvantages:
- Strength Limitation: Mechanical joint has lower strength than hot vulcanized joint.
- Maintenance Requirements: Periodically check bolt fastening is required to prevent loosening.
Quick Pin Splice
Punch finger on the belt two ends, and then drill holes into the belt teeth. The belt is connected by steel pins and the pins number is customized according to belt specification.
Steel Buckle Joint
ATN Connecting Kit
Use plates and inserts to fasten with screws to timing belt, which is particularly used for ATN10 and ATN20 series timing belt.
Cold Bonding Joint
Use a specific cold adhesive to connect the two ends of the timing belt together. Cold bonding joint offers greater connection efficiency and stability than mechanical joint, but it require precise process control and high-quality adhesives to ensure joint strength and durability.
Procedures:
- Cut two ends of the synchronous belt at 45 degree Angle, or use a step cut pattern to increase the bonding area.
- Evenly smear adhesive on the cutting surfaces at both ends.
- Align the belt teeth and press the ends together.
- Use the clamp to hold the belt and wait for the adhesives to solidify.
Advantages:
- Convenient Operation: No vulcanization equipment is required and the operation is easy and fast.
- Flexibility: Joint can be made on site without vulcanization equipment.
Disadvantages:
- Lower Strength: Cold bonding joint has lower strength than vulcanized joint.
- Environmental Effects: The performance of the adhesive may be affected by ambient temperature and humidity
Welded Joint Method
This method is similar to hot melt joint, but it uses special welding equipment and techniques. Welded joint can also provide a high strength and durability connection, which is suitable for timing belts of thermoplastic materials like PU.
Advantages:
- Nearly Seamless Connection: Welding can form an almost seamless joint, reducing the material overflow at the joint part.
- High Cleanliness: Applicable to the food or pharmaceutical industries which require high cleanliness.
Disadvantages:
- Material Limitation: Only applicable to toothed belt of thermoplastic material.
- Equipment Requirements: Professional welding equipment is required.
Flex Timing Belt
Flex timing belt is made from mold, the whole belt is seamless, has no joint. It has the advantage of high strength and even tension of the whole belt, but it limits to the mold length and width.
Conclusion
The selection of timing belt joint method depends on the specific application scenario, load requirements and environmental conditions. For low load or easy maintenance occasions, mechanical or adhesive joints are more practical, while for high load or high precision systems, hot melt and seamless belts are more ideal.
