Selection of materials for sludge single screw pump
In a sludge single screw pump, the material selection of the part that is in direct contact with the medium (i.e. sludge) is crucial, which is not only related to the durability of the pump, but also directly affects its service life and the purity of the treated medium (especially in sensitive industries such as food and medicine). The following is a detailed material selection description for metal parts and rubber parts:
Metal parts
Suction chamber, extrusion chamber, sealing box:
Typically, these parts are made of HT20-40 cast iron, because cast iron has good wear resistance and corrosion resistance, which is suitable for most sludge treatment applications.
For high pressure or high demand occasions (such as pumps above level 4), the extrusion chamber may use ZG25 cast steel to increase its strength and corrosion resistance.
When the medium is highly corrosive, these parts should be made of stainless steel, such as ZG1Cr18Ni9Ti (304 stainless steel) or ZGCr18Ni13Mo2Ti (316 stainless steel), which have good corrosion resistance and can resist the erosion of various chemicals.
Input shaft, intermediate shaft, rotor:
These rotating parts are usually made of structural steel such as 45 or 40Cr, Cr12, etc. These steels have high strength and wear resistance and are suitable for bearing large torque and load in sludge treatment.
In situations where corrosion resistance is required, these parts should be made of stainless steel, such as 1Cr18Ni9Ti or Cr18Ni13Mo2Ti, to ensure their long-term stable operation.
Bearing seat:
The bearing seat is usually not in direct contact with the medium, so it can be made of cast iron or cast steel. These materials have high strength and rigidity, can support the bearing and withstand axial and radial loads.
Rubber parts
Stator and universal joint seal sleeve:
These rubber parts are key sealing components in sludge single screw pumps, and their material selection directly affects the sealing performance and durability of the pump.
Depending on the properties of the medium (such as temperature, pressure, chemical properties, etc.), different types of rubber materials can be selected, such as natural rubber, nitrile rubber, ethylene propylene rubber, chlorosulfonated polyethylene rubber, fluororubber, etc.
In demanding industries such as hospitals and food, all rubber parts in contact with the medium must be made of non-toxic rubber materials that meet food grade standards, such as food grade nitrile rubber or fluororubber, to ensure the purity and safety of the medium.
