Lost foam drying is an important process in the lost foam casting process, this drying is the drying of the lost foam coating, this coating is the powder of quartz, zircon, graphite and other high-temperature resistant materials, mixed binder, stabilizer and water mixed into a slurry-like substance, after spraying or soaking on the lost foam mold, after drying to form a layer of thickness 0After a thickness of 5-2 mm, this thickness needs to be reached after two or three soaks before casting.
Because the coating contains high moisture, it is very important to drain the moisture when drying, if the moisture discharge is not in place, then it will lead to the loss of foam can not be completely dried, so that in the pouring process, there will be quality problems such as burrs and sand sticking caused by cracking of the coating, which will increase the post-processing, or lead to the surface is not smooth, uneven, resulting in a decrease in airtightness, affecting the casting quality.
Traditional drying, in order to solve the problem of dehumidification, is to open a small window in the drying room, so that although the moisture can be discharged quickly, it will lose a lot of heat, and there will be fresh air in the dehumidification process, which will lead to uneven heating of the coating during the drying process, so it will crack, or cause the mold to deform. Therefore, it is recommended to use ZD-45GS series lost foam drying room dehumidifier to dry, it can heat up, can also quickly remove moisture in a closed environment, thermal cycle to ensure that the lost foam coating is evenly heated, to ensure that the lost foam will not be deformed, can speed up the drying speed, improve the casting efficiency.
The process of using ZD-45GS series lost foam drying dehumidifier is divided into three steps, the first is preheating and dehumidification, the temperature is controlled at 25-35, and the humidity is controlled below 30%RH;Then there is constant temperature and humidity discharge, the temperature is controlled at 35-40, and the humidity is controlled below 25%RH;The next is high-temperature drying and dehumidification, the temperature is controlled at 40-50, the humidity is controlled below 20%RH, and the time of the three stages is 3-4 hours, 8-10 hours, and 6-8 hours. Then it's natural cooling, and it's ready to be cast or stored.
Zhengdao ZD-45GS series drying room dehumidifier set heating and air dehumidification functions in one, the applicable temperature is 5-55, compared with the traditional coal drying, no need to take care of the whole process, the whole process through the display screen operation temperature and humidity, can quickly dehumidify, energy saving, environmental protection, no exhaust gas pollution, no combustion emissions, no toxic gas emissions, keep the environment clean, is a good choice for lost foam drying.