What are the installation requirements for metering pumps?

Metering pump installation requirements:

The pump's exterior should be undamaged, and the seals should be intact. The unloading device and pump body flow path of the plunger metering pump, and the exhaust passage and filter of the diaphragm metering pump should be cleaned.

Pump leveling

Before the pump test run, the following requirements should be met:
1. The direction of the drive motor should match the direction of the pump.
2. There should be no loose connecting bolts.
3. Lubricating oil should be added to the adjusting base, safety make-up valve group, pump cylinder cavity, or hydraulic diaphragm cavity in accordance with the equipment technical documents. The hydraulic cavity of the hydraulic diaphragm metering pump must be free of gas.
4. The plunger of the moving plunger metering pump should be reciprocated several times without any jamming. The diaphragm of the diaphragm metering pump should be well sealed.
5. The stroke adjustment mechanism of the plunger metering pump should be sensitive and reliable, and the unloading device should be pressure tested according to the equipment technical documents.
6. The automatic control components of the stroke counter and revolution transmitter should be adjusted correctly. The scale of the metering gauge, the scale of the adjusting handwheel, and the length of the plunger stroke should be adjusted and measured to zero or 100%. The zero-point error of the pump stroke length should not exceed 0.2% of the maximum stroke for an arc cam structure and 0.6% for an N-axis structure.

The following requirements should be met during the pump test run:

1. With the inlet and outlet pipe valves fully open and transporting liquid, the running time should not be less than 0.5h. During operation, the operation should be stable when the stroke length is arbitrarily changed.
2. The pressure should be increased step by step at 25%, 50%, 75%, and 100% of the rated pressure difference. At each discharge pressure level, the running time should not be less than 15min. Finally, it should run continuously for 1h at the rated discharge pressure. If the previous pressure level test fails, the next pressure level test should not be conducted.
3. There should be no abnormal noise during operation.
4. The transmission and adjustment mechanism should operate smoothly.
5. The lubricating oil temperature should not exceed 60℃, and the bearing temperature should not exceed 70℃.
6. Under the rated discharge pressure and conveying room temperature water (oil for diaphragm pumps), the leakage of the plunger packing seal should not exceed the provisions of Table 1-1.

7. The safety valve of the diaphragm metering pump oil chamber should be sensitive and reliable in its operation. Its opening pressure should meet the provisions of Table 1-2. The discharge pressure should be 1.05-1.15 times the opening pressure, and the reseating pressure should be greater than 0.9 times the opening pressure. The automatic oil replenishment valve should operate at a vacuum degree greater than or equal to 80%, and its operation should be sensitive and reliable.

8. The pump's adjustment mechanism should be recalibrated according to the "flow rate, stroke" curve specified in the equipment technical documents, if conditions permit.