Open time of sealing hot melt and feed speed of sealing machine

The opening time of the sealing hot melt glue refers to the period from the beginning of the sealing edge machine to the time before the sealing edge belt is pressed to the substrate. The opening time varies with the rubber species. The feed speed and opening time of the high temperature adhesive and low temperature adhesive of the sealing machine are closely related. Both of them are very important in the selection and use of hot melt adhesive.
The sealing machine with fast feed material must choose the hot melt glue with short opening time, instead, choose the hot melt glue with long opening time. For most manual sealing machines, due to manual operation by workers, it requires that the opening time of the hot melt glue used is long enough to facilitate the sealing of curved parts. Hot melt glue is generally coated on the sealing belt. In order to ensure the quality of the sealing edge, the domestic manual sealing machine also adopts a double-sided coating method.

The temperature of the plastic tank of the manual sealing machine is generally controlled below 180 °C(the German BRANDT manual sealing machine can be heated above 200 °C), so the use of hot melt glue with a temperature below 180 °C is required. If a thin PVC below 0.2 mm thick is sealed on a manual sealing machine, the temperature of use of the hot melt glue used must be about 120 °C.
For automatic or semi-automatic sealing machines, as the substrate and the sealing band are coated and pressed, the end of the sealing band will soon be cut off, repaired up and down, and polished. In these processes, the sealing band will be subjected to mechanical cutting force., Therefore, hot melt glue is required to have a short opening time and a high initial adhesion strength. Especially for thicker sealing materials(such as thick solid wood edge strips), due to the large cutting force, if the initial adhesive strength of the hot melt glue is not enough, the plate and the sealing band will crack. In general, the feed speed of the automatic sealing machine in China is between 8-25 m/min, and the use temperature of the sealing hot melt gum is about 200 °C.