Precautions for use of glass sand core crucible

1. Since the expansion coefficient of the sand core at the bottom of the glass sand core crucible is different from that of glass, the glass sand core is easy to absorb water when it is cleaned. Therefore, after cleaning, it must be dried in an oven at 105 ℃ before it can be used normally.

2. Because glass products are afraid of sudden cooling and heating, the glass sand core crucible can not be taken out immediately after burning at 500 C. It is better to wait until the temperature in the furnace drops to room temperature. After the temperature is reached, the muffle furnace can also be opened by a small crack to speed up the cooling speed, but the door of the muffle furnace can not be opened directly or the crucible can not be taken out directly.

3. When placing the crucible on the instrument for use, remember to clean the dirt on the upper and lower sealing rings, so as not to cause uneven stress on the crucible, resulting in local fracture.

The glass sand core crucible has a service life. Pay attention to the above three points, which should be able to prolong the use of the crucible.