GB/T 7782-2020 in English

Plunger metering pumps shall meet the following requirements under rated conditions:

• Flow metering accuracy±1% (clean water medium)
• Packing seal leakage≤0.01%Q (Q≥10L/h)
• Noise value≤85dB(A) (pressure 32-50MPa)

Diaphragm metering pumpsAdditional requirements for hydraulic chamber safety valves:

• Opening pressure1.1-1.25 times rated pressure
• Reseat pressure≥0.8 times the opening pressure

The new standard strengthens the test requirements:

1. Newly added vibration test (GB/T 13364)
2. Pressure pulsation measurement value ≤ 10%
3. Adjustment range test needs to verify 10%-100% stroke

Cavitation test adopts vacuum container method or deep well method, critical point judgment standard:

Net positive suction pressure head when NPSHr = (Qn×97%)

Manufacturers should focus on:

• Hydraulic chamber components need to be redesigned and verified
• Establish a cleanliness control system (refer to Table 2)
• Vibration test equipment upgrade

User acceptance notes:

• Check the completeness of the test records in Appendix D
• Verify the adjustment range area diagram (Figure 2)
• Confirm the safety valve pressure calibration certificate