The effect of mould preheating and several methods of preheating
Natural (coal) gas heating: a widely used method. Applicable to different mould shapes. The heater is made of pipes, and there are many small holes in it, and the gas is ejected and the size of the fire can adjust the air valve to achieve it. Clean without pollution, can be heated locally. The disadvantage is that it is controlled by people, and it is easy to burn the mold.
Mould temperature machine (oil) heating: the heating is even, the temperature adjustment adopts intelligent control, the temperature control accuracy is high, can meet the strict requirement of high craft standard. The operation control and safety monitoring device is fully complete, the heating process is fully automatic, the operation is simple, and the installation is convenient. Closed circuit heating, low heat loss, significant energy saving effect, no environmental pollution, wide range. The drawback is that heating is transmitted by heat, which is slower
In order to protect the mould and improve the efficiency of the mould, it is necessary to keep the mould working in a certain temperature range as much as possible. If the mould no preheating, on the other hand, due to the mold temperature is low, it is easy to cause molding difficult, mucous membrane, the casting defects such as cracks, on the other hand, due to the mold temperature change is too big, hot and cold stress is very big, it is easy to mold damage, severe cases, may cause mould crack. Therefore, pre-heating is very important. According to the heating method, it can be divided into electric heating, natural (coal) gas heating and temperature heating. 1) electric heating: the heat tube is mainly heated by heat tube, which is clean and convenient to use. The drawback is that the thermal radiation is small. Die casting die is not adopted normally.
