② The amount of calcium-based grease used for lubricating bearings should occupy 1/3 to 1/2 of the bearing housing space.
    ③ When packing wears, appropriately tighten the packing gland. Replace it if excessive wear occurs. ④ Regularly inspect coupling components and monitor motor bearing temperature rise. ⑤ If abnormal noise or other unusual sounds occur during operation, immediately stop the pump, investigate the cause, and eliminate it. ⑥ Do not arbitrarily increase the pump’s rotational speed, but it may be operated at reduced speeds. For example, if this pump type has a rated speed of n, flow rate of Q, head of H, and shaft power of N, and the reduced speed is n₁, the flow rate, head, and shaft power after reduction become Q₁, H₁, and N₁ respectively. Their interrelationship can be converted using the following formula. Q₁ = (n₁/n)Q H₁ = (n₁/n)²h N₁ = (n₁/n)³N1. Assemble the rotor components: Sequentially install the impeller, shaft sleeve, shaft sleeve nut, packing sleeve, packing ring, packing gland, water seal ring, and bearing assembly onto the pump shaft. Fit the double-suction seal ring, then install the coupling. 2. Mount the rotor assembly onto the pump casing. Adjust the impeller’s axial position to center between the dual suction seal rings on both sides and secure it. Tighten the bearing housing cover with the fixing screws. 3. Install the packing, position the center-opening paper gasket, cover with the pump cover, tighten the threaded stud pins, then secure the pump cover nuts. Finally, install the packing gland cover. Do not compress the packing excessively tight, as this causes sleeve overheating and increased power consumption. Conversely, avoid excessive looseness, which leads to significant liquid leakage and reduced pump efficiency.
    After assembly, manually rotate the pump shaft. It should turn smoothly and evenly without any rubbing or binding. Disassembly can be performed in the reverse order of the above assembly steps.
SH Type Double-Suction Clean Water Centrifugal Pump Installation
    1. Inspect the pump and motor for damage.
    2. The pump’s installation height, combined with suction piping hydraulic losses and velocity head, must not exceed the allowable suction vacuum height specified in the catalog. Foundation dimensions must match the pump unit’s installation requirements.
    3. Installation sequence: ① Place the pump on the concrete foundation with embedded anchor bolts. Level it by adjusting wedge shims between the pump and foundation, then securely tighten the anchor bolts to prevent movement.
    ② Pour concrete between the foundation and the pump base.
    ③ After the concrete has cured, tighten the anchor bolts and recheck the pump’s levelness.
    ④ Align the motor shaft with the pump shaft concentrically. Ensure both shafts are in a straight line. The concentricity tolerance on the outer circumference of the coupling is 0.1mm, and the circumferential unevenness tolerance of the end face clearance is 0.3mm (recheck these after connecting the inlet/outlet pipes and trial operation; they must still meet the above requirements). ⑤ After verifying that the motor rotation direction matches the pump rotation direction, install the coupling and connecting pins. 4. Inlet and outlet piping must be supported by separate brackets and shall not bear on the pump body.
    5. The mating surfaces between the pump and piping must ensure good airtightness, especially the inlet piping, which must be strictly airtight with no potential for air pockets in the system.  
    6. When installing the pump above the water level, a foot valve is generally installed for priming and starting. Alternatively, vacuum priming may be employed.
    7. A gate valve and check valve are typically required after the pump and discharge piping (not required for head less than 20 meters). The check valve is installed downstream of the gate valve.
    The installation methods described above apply to pump units without a common baseplate.
    For installing pumps with a common baseplate, level the unit by adjusting the wedge shims between the baseplate and the concrete foundation.
  Then pour concrete into the space. Installation principles and requirements are identical to those for units without a common base. 
SH Type Double-Suction Clean Water Centrifugal Pump Start-up, Operation, and Shutdown
  1. Start-up and Shutdown:
  ① Before starting, rotate the pump rotor. It should turn smoothly and evenly. ② Close the outlet gate valve and fill the pump with water (if no foot valve is present, use a vacuum pump to draw in water). Ensure the pump is completely filled with water and no air pockets remain. ③ If the pump is equipped with a vacuum gauge or pressure gauge, close the connecting plug valve before starting the motor. Open it only after the speed stabilizes. Then
gradually open the outlet gate valve. If flow is excessive, adjust by partially closing the valve; conversely, open the valve further if flow is insufficient. ④ Uniformly tighten the packing gland’s compression nuts until liquid drips out, while monitoring temperature rise at the packing chamber. ⑤ When stopping pump operation, first close the vacuum gauge and pressure gauge valves, then the outlet gate valve. Subsequently, shut off the motor power supply. If the ambient temperature is low, open the square drain plug at the bottom of the pump housing to remove residual water, preventing freezing damage. ⑥ For long-term storage, disassemble the pump, thoroughly dry all components, apply rust-preventive oil to machined surfaces, and store properly. 2. Operation: ① The maximum bearing temperature should not exceed 75°C.