Common problems and treatment of hot press

The production of hot press is closely related to our life, many plate production can not do without the hot press, but occasionally there are some problems that make us very headache. Let's take a look at what problems we will encounter and how to deal with these problems.

Problem 1 - plywood debonding. The reasons for this situation are: uneven coating or insufficient glue; too low hot pressing temperature or short time; excessive moisture content of veneer; too long aging time, resulting in glue drying. The corresponding treatment methods: pay attention to the proper amount of glue and apply evenly; increase the hot pressing temperature and prolong the hot pressing time; strictly control the moisture content of veneer; control the aging time.

Problem 2 - plywood blistering. There are three reasons for this problem: the hot pressing temperature is too high or the speed of depressurization is too fast; the moisture content of veneer is large or the drying treatment is not uniform; the condensation degree of resin is not enough. Solution: the speed of the second stage of the depressurization process should be slow, and the hot pressing temperature should be reduced at the same time; the moisture content of veneer is generally between 8% and 12%, which must be strictly controlled; when selecting resin, check the quality of resin and select the resin that meets the requirements.

Problem 3 - the thickness of plywood exceeds the allowable difference range. The causes of the problem are: the pressing plate or plunger are inclined; the hot pressing quantity in each interval is too large; the thickness calculation of plywood slab is wrong. Treatment plan: adjust the machine to the level before working; adopt the technology of one sheet one pressing; calculate and adjust the slab matching thickness.