4.2.11 Bel-Top Chain
Top Chain: Engineered plastic belt-shaped chain. Bottling, canning, and general uses
Bel-Top Chain offers the power and reliability of a chain system with the smooth operation of a belt. The chain is used for linear conveyance, accumulation, side loading, and movement of cans, bottles, or other materials that are easily scratched (Figure 4.17).
Accumulation and movement with Bel-Top Chain is smoother than a system with several strands of Engineered Plastic Top Chains. In addition, the Bel-Top Chain system, including guide rails and other parts, costs less.
Construction and Features
- The chain consists of engineered plastic modular links with small pitch (19.05 mm) and pins. It combines the functions of a chain and belt (Figure 4.18).
Figure 4.17 Bel-Top Chain
Figure 4.18 Bel-Top Chain Combines the Features of Chains and Belts
- There are two types of Bel-Top Chain; MWB type has low-friction and anti-abrasion, KV-type has heat resistance (endures continuous temperatures of up to 250°C) and high-speed resistance. Each type uses different engineered plastic.
- Pins are made of engineered plastic in MWB-type and stainless steel in KV-type. There are specially shaped snap rings installed on both ends of the pin to prevent it from falling out.
Special features include the following:
- Large conveying width (up to 3 m).
- No slippage due to positive engagement with sprockets.
- Easy to maintain. The chain consists of only three parts; therefore, it is easy to assemble, connect, and disconnect. If a single link breaks, only the broken parts need to be replaced.
- Considering small chain pitch, small sprockets may be used to ensure smooth transfer between conveyors.
- Sprockets prevent tracking problems. This condition is difficult to prevent when using a conventional belt.
- It is easy to maintain a clean and sanitary operation. Therefore, the chain is widely used in the food industry.
Use special engineered plastic sprockets with 10 teeth (P.D. 61.65 mm) for a hexagonal steel shaft, or 24 teeth (P.D. 145.95 mm) with a square steel shaft. When 10-tooth sprockets are used, the area between conveyors can be minimized. On the other hand, 24-tooth sprockets offer smoother engagement with the chain, and chordal action is reduced.
When conveying light products, the lateral distance between sprockets may be extended. Refer to the manufacturer's catalog for details.
Selection and Handling
- Maximum allowable load of both MWB-type and KV-type is 1.96 kN for 1,524-mm-wide chain. However, this value is affected by temperature and speed. When the chain width is greater than 1,524 mm, check the manufacturer's catalog for maximum allowable load.
- "Open type" of MWB-type has holes in the upper panel. These can be used in a variety of applications. For example, you can drain liquid or allow air flow through the chain during the operation.
- It is important to allow for catenary, and to install take-up on the return side. Special consideration needs to be given to the heat expansion of KV-type.