Ebara CVM B/23 [6/18] Curve specifications

MULTISTAGE CENTRIFUGAL PUMPS CVM

TYPE KEY AND CURVE SPECIFICATIONS 50Hz

203

EBARA PUMPS EUROPE S.p.A.

Rev. I

PERFORMANCE CURVE SPECIFICATIONS

The specifications below qualify the curves shown on the following pages.

Tolerances according to ISO 9906:2012 - Grade 3B

The curves refer to effective speed of asynchronous motors at 50 Hz, 2 poles.

Measurements were carried out with clean water at 20°C of temperature and with a kinematic viscosity

of ν = 1 mm

/s (1 cSt)

The NPSH curve is an average curve obtained in the same conditions of performance curves.

The continuous curves indicate the recommended working range. The dotted curve is only a guide.

In order to avoid the risk of over-heating, the pumps should not be used at a flow rate below 10% of best

efficiency point.

Symbols explanation:

volume flow rate

total head

pump power input (shaft power)

pump efficiency

NPSH

net positive suction head required by the pump

MEI

minimum efficiency index

The minimum efficiency index (MEI) is a measure of the quality of a pump size in respect to its mean

efficiency. The minimum efficiency index is based on the hydraulic efficiency and on the head at the best

efficiency point.

The efficiency of a pump with trimmed impeller is usually lower than that of a pump with the full impeller

diameter. The trimming of the impeller will adapt the pump to a fixed duty point, leading to reduced

energy consumption. The minimum efficiency index (MEI) is based on the full impeller diameter.

The operation of these water pumps with variabile duty points may be more efficient end economic when

controlled, for example, by the use of a variable speed drive that matches the pump duty to the system.