Type series STU4. CP constant pressure version

Power range from approx. 8 m³/h and 140 m discharge head

STÜWA 4“ submersible pumps have been designed in the successful step-by-step way of construction: completely made of stainless steel with a wall thickness of 1.0 mm. Thus, we achieve an excellent resistance to abrasion by gritting materials such as sand etc. The built-in strainer prevents the infiltration of larger foreign bodies. Therefore, our pumps are ideally suited for production of drinking water. For the constant pressure version motors by SUMOTO are used.

When using the constant pressure version, excellent performance data are achieved with speeds between 3,000 and 5,350 RPM; power range up to 8 m³/h and 140 m discharge head.

Available in 230 V, 50 Hz up to 90 Hz from 1.1 kW up to 2.0 kW

  • Water supply for domestic and general purposes
  • Small water works and wells
  • Irrigation
  • Container applications
  • Pressure increase
  • Heat pumps
  • Drainage
  • Mining industry
  • Industrial applications

Flow media:
Our submersible pumps of the STU4. or STU4. CP type series are made for the conveyance of thin, clear, non-aggressive and non-explosive liquids without solids.

The pumps are suited for the conveyance of liquids with a sand content of up to 150 g/m³. A higher sand content shortens the operational life span of the pump.

The permissible temperature of the flow medium amounts to max. 30 °C.

Installation conditions:
Our submersible pumps of the STU4. or STU4. CP type series can be installed horizontally or vertically. In order to ensure a sufficient cooling of the motor, the minimum inflow velocity of the flow medium must amount to at least 8 cm/sec at max. 30°C.

Conditions of characteristic curves:
Tolerances of characteristic curves compliant to ISO 9906:2012 Grade 3B.

The characteristic curves state the pump performance using our standard motors with a standard rotational speed at 50 Hz.

The characteristic curves have been ascertained at a water temperature of 20 °C and in airless water, and remain valid at a kinematically determined viscosity of 1 mm²/sec.

Should liquids of a higher viscosity be pumped up, motors with adequately higher power must be employed.

The characteristics already allow for valve and inlet losses at standard rotational speed values of 50 Hz.

Power characteristic:
P2 shows the power requirements of the pump at the standard rotational speed of 50 Hz for each individual pump size.

Efficiency characteristic:
η efficiency of a single pump stage.

The STU4. CP control comprises variable speed, flow measurement and pressure sensor.

Our submersible pumps of the STU4. CP series in constant pressure version are supplied as installation kit and consist of the following parts:

  • Stainless-steel submersible pump STU4. CP complete with submersible motor in high-speed version for a frequency control up to 90 Hz.
  • Constant pressure control incl. flow monitor and pressure sensor
  • Pressure tank with a holding capacity of 8 litres
STÜWA 4“ submersible pump STU4. CP
STU4. CP series installation kit
Upper bearing
Upper bearing
Shaft with NEMA-coupling
Shaft with NEMA-coupling