Type OWZ

Qmax=500 m3/h – Hmax=262 m 


OWZ pumps are typically applied for open cast mine and deep mine dewatering. They are also applicable in any other case when submersible pumps of high capacity and head are required to pump contaminated water.


Multi-stage, vertical, submersible centrifugal pumps with closed impellers and vane diffusers. Water inlet is located around the perimeter between then pump and the motor while the delivery flange is directed vertically upwards. The pump is designed to operate hanging on the delivery pipeline.

The slide bearings are installed in oil chambers sealed by mechanical seals. Thus the presence of abrasive solids in the pumped fluid does not affect the bearing operation. The upper Mitchell type bearing absorbs the axial thrust. For smaller sizes both the radial and axial bearing are roller type, oil lubricated.

The pump is driven by 6000V electric dry type motor with IP X8 degree of protection located under the pump. The power from electric motor is transmitted via a flexible coupling. The motor has own roller bearings. The pump set is equipped with the monitoring system including bearings and motor windings temperature sensors as well as water presence sensors in the oil chambers and in the motor.


Impellers, diffusers, casings are made of cast steel.
Shaft, bolts, nuts – stainless steel.


Part name


Part name

1 Electric motor 9 Bearing housing
2 Suction casing 10 Discharge casing
3 Tie bolt 11 Coupling
4 Centrifugal guide 12 Suction strainer
5 Supply guide 13 Shaft
6 Impeller 14 Oil
7 Stage casing 15 Oil tank
8 Seal casing

Pump type

of stages

Dimensions [mm]





OWZ-250A 3 3638 1095 425 250
4 3967
5 4162
6 4357
7 4552

Pump type

Number of stages

Q [m3/h]

H [m]

Rotation speed
n [rpm]

Motor rated power
Ps [kW]

m [kg]

OWZ-250A 3 500 114 1500 315 6824
4 151 315 7013
5 188 500 7202
6 225 500 7391
7 262 500 7580

The parameters are specified for clean water of density ρ=1000 kg/m3 and temperature T=15°C.