At present, there are three main types of insulation methods for domestic asphalt screw pumps:
1. The electric heating belt is wound on the outside of the screw pump. The biggest advantage of this method is that the screw pump does not need to adopt a special structure, and the structure is simple and inexpensive, but the heating effect is poor and the safety is poor. This method has rarely been adopted so far.
2. By heating from the bottom of the screw pump through steam or heat transfer oil, the advantage of this method is that the structure is simple and inexpensive, but because it is not the overall heating, the heating effect is poor and the work reliability is poor.
3. The screw pump adopts jacket type, and the jacket is divided into two types: integral jacket and insulation circuit. The heat preservation carrier is steam or heat transfer oil. The advantages of this method are good heating effect, strong work reliability and long service life. The disadvantage is that the screw pump structure is complicated and expensive.