Band Machines

Premade bags are ideal for many packing operations. They can be hand or machine loaded but then the open top needs to be sealed. Band sealers are just the thing for this. They will work with a variety of bag materials provided always that the inside of the bag material is heat sealable.

The band sealer consists of a conveyor to support the bag and a pair of thin, horizontal fiberglass belts, facing each other and running in the same direction. Heating and cooling sections are located behind and in direct contact with the belts on either side.

The product is placed on a conveyor that is running in synchronization with the sealer. The top portion of the bag is manually straightened to eliminate wrinkles and guided between the two belts. As the belts grip the bag, the operator releases it and lets the sealer and conveyor do the rest of the work.

As the bag enters the heated section of the sealer, heat is transferred through the belts to the bag. Springs press the belts and plates against the bag with a controlled force. The combination of belt pressure, heater temperature, and speed (dwell time) determine the quality of the seal.

Immediately after sealing, the seal is still hot and has not yet set up. Any stress on it at this point could result in failure. After leaving the heated section of the sealer, the bag, still gripped by the sealing belts and supported by the conveyor enters a cooling section. This consists of cooling blocks, cooled by circulating air around them. As the bag is carried through the cooling section, the seal is cooled to near room temperature and takes a permanent set.

The conveyor, moving at the same speed holds the bag straight while in the sealer.

An optional feature on some bag sealers is a cut-off to remove excess bag material above the seal.

Another option is an integrated coder to apply a lot number, expiration date or other variable information. This can be debossing wheel or an inkjet printer.