The suction and discharge ports of the pump are both vertically upwards, and the axial force of the rotor is balanced by a balance plate. The shaft seal can be a packing seal or a mechanical seal. The rotor support only uses sliding bearings for DG85-80, DG85-67, and DG155-67, lubricated with thin oil, while other pumps use rolling bearings.
1. Pump housing section
The pump casing is mainly composed of a bearing body, front section, middle section, rear section, guide vanes, etc., which are connected by bolts to form a whole. The centerline of the front suction inlet is horizontal, and the outlet of the rear section is perpendicular to the horizontal.
2. The rotor part mainly consists of a shaft and components such as an impeller, shaft sleeve, and balance plate installed on the shaft. The parts on the shaft are fastened with flat keys and shaft sleeve nuts to form an integral part with the shaft. The entire rotor is supported by bearings at both ends on the pump casing, and the number of impellers in the rotor section is determined by the number of stages of the pump.
3. Bearing section
This type of pump has two types of bearings: sliding bearings and rolling bearings, depending on the model, neither of which can withstand axial forces. The pump should allow the rotor part to move axially in the pump housing during operation, and radial ball bearings should not be used
4. Sealing of the pump
The sealing surfaces between the front, middle, and rear sections of the pump are all sealed with molybdenum disulfide grease. The rotor and fixed parts are sealed by sealing rings, guide vane sleeves, fillers, etc. When the wear of the sealing rings and guide vane sleeves has affected the operation and performance of the pump, they should be replaced.
When using this type of pump, the position of the packing ring should be placed correctly. The distribution of the packing and packing rings for each type of pump is shown in Table 2. The tightness of the packing must be appropriate, and it is advisable for the liquid to seep out drop by drop.