What is traffic? What letter is used to represent it? How to convert?

The volume of liquid discharged by the pump per unit time is called flow rate, which is expressed in Q and measured in cubic meters per hour (m3/h), liters per second (l/s), L/s=3.6 m3/h=0.06 m3/min=60L/min

G=Q ρ G is the weight ρ Is the specific gravity of the liquid

Example: A certain pump has a flow rate of 50 m3/h, and can we calculate the weight per hour when pumping? Specific gravity of water ρ It is 1000 kilograms per cubic meter.

Solution: G=Q ρ= fifty × 1000 (m3/h · kg/m3)=50000kg/h=50t/h

What is lift? What letter is used to represent it? What unit of measurement is used? Conversion and formula for pressure?

The energy obtained by a unit weight of liquid through a pump is called head. The head of the pump, including the suction head, is approximately the pressure difference between the pump outlet and inlet. The head is expressed in H, in meters (m). The pressure of the pump is expressed in P, in Mpa (megapascals), and H=P/ ρ. If P is 1kg/cm2, then H=(lkg/cm2)/(1000kg/m3) H=(1kg/cm2)/(1000kg/m3)=(10000 kg/m2)/1000 kg/m3=10m 1Mpa=10kg/c m2, H=(P2-P1)/ ρ (P2=outlet pressure P1=inlet pressure)

What is cavitation margin? What is suction range? What are the letters for each unit of measurement?

When a water pump is working, the liquid at the inlet of the impeller will generate vapor under a certain vacuum pressure. The vaporized bubbles will cause erosion on the metal surface of the impeller under the impact motion of the liquid particles, thereby damaging the impeller and other metals. At this time, the vacuum pressure is called vaporization pressure, and the cavitation margin refers to the excess energy per unit weight of liquid at the pump inlet that exceeds the vaporization pressure. The unit is indicated in meters and expressed in (NPSH) r. The suction head is the necessary NPSH Δ h: The vacuum degree that the pump is allowed to absorb liquid, which is the allowable installation height of the pump, in meters.

Suction lift=standard atmospheric pressure (10.33 meters) - NPSH - safety (0.5 meters)

The vacuum height of the standard atmospheric pressure pipeline is 10.33 meters.

For example, if the NPSH of a certain pump is 4.0 meters, calculate the suction head Δ H?

Solution: Δ H=10.33-4.0-0.5=5.83 meters