The temperature control method of hot melt adhesive

2021/05/23

    In the first case, the curing time of the hot melt adhesive is directly related to the initial temperature, and the corresponding curing time will be prolonged at high temperatures, and vice versa;

    In the second case, the fluidity of the hot melt adhesive is directly related to the temperature, and the fluidity is good at high temperatures. The impact is that the permeability of the hot melt adhesive increases, but the amount of glue is smaller. If the temperature is low, the permeability of the hot melt adhesive will become poor, and the adhesive will not be able to be adhered. The amount of glue will increase. Especially the roller coating method can greatly increase the amount of glue. Intensity has no positive effect.

 

The temperature control method generally adopts the switch type and the circuit breaker switch type, and the control result often has a deviation of more than 10 , and some thermocouples are improperly matched or even have a larger range of variation. In addition, PID is used to control the temperature control method. When the actual temperature is close to the set temperature, it will be adjusted by the duty cycle, or by the way of chopping, so that the temperature rise speed is reduced, so that the temperature rise does not produce overshoot, generally The cooling process uses natural heat dissipation to cool, without active control. Using this PID control method, the temperature change range can be controlled within 1°C, because the adverse effects caused by large changes in temperature can be eliminated.