Centrifugal pumps or sewage pumps for high-viscosity liquids cannot meet the requirements of working conditions. The result of using these two pumps is that the speed of the pump motor slows down. The motor burns out because the motor cannot burn out the liquid for a long time. Is the screw pump suitable for conveying high viscosity liquid? Then we will analyze the following:

The single screw pump is a kind of high viscosity pump which was widely used earlier. The rotor is a single-headed male screw made of metal (circular on the section perpendicular to the axis), and the stator is mostly a special double female screw made of rubber (the shape of the hole on the section perpendicular to the axis is a racetrack shape). The sealing line formed when the rotor rolls in the stator gradually moves to the outlet end, so that the liquid moves from the inlet to the outlet along the axis. The advantage of the pump is that the delivery is stable, the pulsation is small and the material has no stirring effect, and it is not sensitive to solid particles. However, due to the large frictional resistance, its energy consumption is significantly higher than other forms of rotor pump. As compared with the gear pump, in the same flow, pressure and other indicators, the power configuration is basically 3:1. In addition to its stator material and other factors, the stator wear quickly, need to be replaced frequently, and can not be used in high temperature occasions.

Twin screw pump (asphalt pump) working rotor for two screw shaft of the same size, a shaft on the left-hand thread and another shaft on the right-hand thread meshing. Due to the role of synchronous gears, the two shafts do not contact each other, but maintain a gap of about 0.05~0.15mm, thus forming an independent sealed cavity. With the rotation of the screw, the liquid in the sealed cavity is taken from the inlet to the outlet. Twin screw pump (asphalt pump) has some advantages of single screw pump and cam pump. In recent years, the structure of twin screw pump has been greatly optimized. For example, the left and right screw threads are processed on the same screw shaft to offset the axial force, the external rolling bearing is changed to the internal sliding bearing (copper sleeve) that directly supports the outer circle of the screw, and the synchronous gear is also changed to the middle of the screw, thus greatly simplifying the structure, and the leakage point is reduced to one. However, since the synchronous gear is immersed in the high-pressure medium of the outlet part, it is obviously not suitable for high temperature or strong corrosive medium. Due to the high precision of screw processing, assembly and operation, it is more sensitive to impurities, especially when the material reacts.