BFM Global Ltd. has introduced weighing bellows, a durable, affordable alternative to silicone.
Weighing bellows are commonly used in the food and pharmaceutical industries as the flexible transition between mixers, feeders, dosing equipment and other machinery where accurate weighing is required. Designed to minimize vertical movement or vibration on the weighing/load cells, commonly made from flexible, molded silicone rubber.
Although molded silicone rubber is used, it does have two drawbacks for use as a flexible connection—very poor tear strength and a high price tag. They are usually fastened using manually adjusted systems like hose clamps, making them difficult to fit. This makes molded silicone connectors a high-risk option from an overall cost-efficiency perspective—they are expensive to stock but easy to break. Many customers have often experienced product failures during installation, as one small slip with a screwdriver or hose clamp can tear the material—a costly mistake.
BFM’s alternative solution is a new, patented BFM fitting Weighing Bellows combines the snap-fit installation and seal of a BFM fitting connector with the strength and flexibility of their urethane-based Seeflex material.
Matthew Bailey, BFM’s technical lead in charge of new product development, says the company has spent a lot of time perfecting the method of forming the Seeflex material into the new BFM Weighing Bellows to ensure minimal reactive force for weigh-scales but maximum durability for longevity of the connector itself. “Seeflex is super flexible but has amazing wear resistance,” says Bailey. “We’ve molded it into an asymmetrical cone shape to minimize the possibility of any product staying inside the connector during operation, which can happen with single-fold style bellows.”
The Seeflex material has mechanical properties that exceed those of the incumbent silicone weigh scale connectors or other urethane versions. The company states that it is virtually indestructible in normal use, and BFM fitting Weighing Bellows won't rip or tear during installation or operation like silicone.
The BFM design is 3A and EU-approved for food contact and ensures valuable powders stay inside the connector with zero leakage. This is important for pharmaceutical manufacturers where the processed product is often expensive. It reportedly also helps lose weight feeders as no product is lost during loading.
Unlike most silicone weighing bellows, which are opaque, Seeflex, used to manufacture the BFM Weighing Bellows, is a transparent material that gives visibility to the product flowing through your process. Because no tools are necessary for installation, there is no risk of screwdrivers, clamps or gaskets damaging the connector or falling into the downstream equipment, potentially causing product contamination.
The BFM Seeflex material and the patented blue-band cuff and spigot system are food-grade and are compliant with relevant 3A and EU regulations.