Hot melt units

Hot melt units form the basis of a hot melt system. The hot melt unit consists of several components.

Glue tank

The glue tank is the hot holder, premeltifier and holding tank for an adhesive system. This glue tank is often heated at the bottom. The size of the glue tank is often related to the melting capacity of the unit. Newer melt-on-demand systems have a very small melting chamber, which is often filled with an autofill system.

Glue pump

The glue pump is usually a plunger pump, this is a relatively simple double-acting plunger pump that suffices in many applications. The pump is easy to operate also if more or less glue is needed, this is easily adjusted by adjusting the air pressure on the pump. The inlet air pressure is usually increased by a factor of 1:14 to the glue pressure.

Gear pump

A gear pump is usually used when it needs to apply the adhesive continuously, as the plunger pump has a short depressurisation moment at the tipping points. A gear pump can also handle higher viscosity hot melt adhesives.

Electronic control

The hot melt unit is electronically controlled and regulated. In the controller, things like temperature, timer and standby temperatures can be controlled. Sometimes, timing can also be controlled by these electronics.

Hose connections.

Usually in conjunction with the capacity of the hot melt unit, a number of hose connections are available. These hose connections also include an electrical coupling for controlling the glue heads.