How is EVA hot melt adhesive preheated?

The use of hot melt adhesive requires appropriate preparation and preheating to ensure smooth operation.

1. Glue

Add an appropriate amount according to the amount of glue used and the size of the hot melt glue pool. During normal use, maintain a liquid level range of 35% -80% in the sol tank. If the amount of hot melt adhesive used in a single use is small, there is no need to add too much. Generally, the liquid level can be controlled at around 50%, otherwise it will cause the hot melt adhesive to melt repeatedly, resulting in energy waste, and under the repeated high temperature of the heating tube, the hot melt adhesive will deform locally. Hot melt adhesive melts.

2.  Warm up

Solid hot melt adhesive must be preheated before use and must be preheated to a liquid state before use. The temperature adjustment should not be too high, as the initial melting state is relatively slow, especially for EVA hot melt adhesives. In  205°C  The above will undergo partial decomposition. There are two heating methods for existing equipment, one is oil bath heating; Another type is electric heating plate heating. In terms of performance, oil bath heating is better, and its advantage is temperature stability. The direct heating market share of electric heating plates is relatively high, basically reaching over 80%. The reason is that the structure is simple and the cost is low. The carbonization of melt adhesive, especially when the temperature is too high, has a greater impact in this regard. The preheating time is generally 2 hours, and the temperature setting center value is 140~160 ℃. As the amount of hot melt adhesive increases, the upper and lower temperature limits are often set at 140 ℃ and 190 ℃.