200QW250-18-22 Sewage Pump: Factory Test Results

Rather than repeat the catalogue figures, this page walks through the factory performance test of the 200QW250-18-22, a DN200 submersible sewage pump rated at 250 m³/h and 18 m with a 22 kW motor. The pump was tested in clean water at about 1475 r/min, a 4-pole speed.

Flow (m³/h)	Head (m)	Shaft power (kW)	Pump efficiency (%)
0	28.83	11.06	0
90.55	24.98	13.18	43.68
177.26	22.32	16.16	62.89
252.23	19.08	18.11	68.61
304.41	16.45	19.26	67.36
392.40	10.16	19.49	53.02
451.87	3.63	20.08	21.20

What the numbers tell you

At the rated 250 m³/h, the test measured 19.19 m of head, about 1.2 m more than the 18 m rating, with a unit efficiency of 59.79%. Pump efficiency peaks at 68.61% at 252 m³/h, so the rated point and the best efficiency point line up almost exactly. A pump working at its best efficiency point runs with the least vibration and the lowest energy cost per cubic metre.

Shaft power reaches about 20 kW at the far end of the curve (452 m³/h), within the 22 kW motor rating. That matters in practice: if the real system head turns out lower than planned and the pump runs further out on its curve, the motor is still not overloaded.

With the valve closed, the pump builds 28.83 m. This is the highest pressure the discharge pipework will see from the pump, which is useful when you choose pipe and valve ratings.

The complete test report, with all 12 test points, is on our Technical Support page: https://www.haquanpump.com/support#documents