Automatic and Safe Filling of Hot Melt Equipment

Accidents at the workplace can have serious consequences, not only for the health of the affected employee, but also financially for the company. For this reason, “Safety First!” is an established term in the work environment. A protected and safe work environment must be established for the employees and measures implemented to prevent possible dangers.

Hot melt adhesive is used in the manufacturing process of diverse goods, either for the product itself, or later in the packaging. Hot melt adhesive application systems reach temperatures of up to 200 °C. For this reason, utmost care and respective protective clothing are required when filling the melter with adhesive in granular form.

When opening the tank, there is a risk of splashing of already melted adhesive and of burns on contact with hot components of the adhesive system. There is also a risk of contamination entering the tank and object falling into it causing the operator to reach into the hot tank reservoir. These safety risks can be avoided with an automatic filling system.

Automatic filling of melters mainly serves operator protection. As another advantage, continuous supply of the adhesive system with adhesive in granular form is ensured. Thus, no cost-intensive production interruptions occur.

Differently from manual filling, automatic filling does not fill granulate directly into the hot tank, but into a separate, safe and unheated granulate container called GlueFill. Thus, this process does not bear any risk of burns.

The GlueFill is available in three sizes, allowing the refilling intervals to be reduced depending on demand and application. Using the GlueFill model L and M, up to two melters can be filled at the same time. Applications with small adhesive consumption can also benefit from safe filling using the smallest container size S. As large amounts of adhesive in granular form tend to clump, a filling grid is available as an option for the GlueFill L, which breaks down clumped adhesive granulate so that if falls loosely into the container. The current granulate filling level can be easily checked through a window on the front side of the container.

The automatic filling system RobaFeed 3 consists of a filling tube and air filter on the tank lid of the melter. As additional safety measure, an optional lock prevents tank opening by untrained personnel. The air filter cleans any occurring adhesive vapors. The filling tube is connected to the GlueFill granulate container using a transport hose. A filling level sensor is located on the bottom of the tank lid. It monitors the filling level of the melted adhesive in granular form in the tank reservoir. If the defined minimum filling level is undercut, automatic filling is started by the device control and the pneumatic unit on the container activated. An intake unit with vibrator is inserted in the loose granulate of the respective container. The vibrator loosens the granulate and the intake nozzle generates an underpressure so that the granulate is drawn in and conveyed. The GlueFill L offers additional granulate loosening prior to intake using a vibrator plate as an option.

To overcome longer distances from melter to GlueFill (> 10 m), a special distance amplifier for increased suction effect is available as an option for the transport hose.