Submersible pump 4" without motor, ST-25-16-M4-6/4" hydraulics

Advanced hydraulics for demanding applications

The hydraulic part of the STAIRS ST-25 submersible pump is a professional solution designed for pumping groundwater from deep wells and boreholes. The device achieves an impressive maximum capacity of 100 l/min at a lifting height of up to 102 meters, making it an ideal choice for installations with high hydraulic requirements.

The design based on the NEMA standard with a 4-inch diameter ensures compatibility with a wide range of electric motors available on the market. The system can operate with a medium at a maximum temperature of 35°C and water containing up of 150 grams of sand per cubic meter, which significantly expands the range of possible applications.

Materials and structural resistance

Key structural elements are made of high-grade AISI 304 stainless steel, which is characterized by exceptional resistance to corrosion and aggressive aquatic environments. This applies to the pump housing, discharge and suction ports, cable cover, and impeller hubs.

The pump shaft is also made of AISI 304 stainless steel, while the impellers are made of Noryl - a thermoplastic material with high mechanical and chemical resistance. The shaft bushing is constructed from a carbon/graphite/PTFE composite, ensuring optimal friction and long-term operation without lubrication.

Protection and safety systems

The pump is equipped with a check valve located in the discharge port, which automatically prevents the medium from flowing back after the device is turned off, protecting the installation from hydraulic damage. Additionally, the system features a built-in stainless steel strainer, which effectively protects against the ingress of larger solid particles into the pump.

The plain bearing made of polyoxymethylene (POM) is characterized by high abrasion resistance and dimensional stability across a wide range of operating temperatures.

Operating parameters and efficiency

The device is designed for continuous operation in the most difficult environmental conditions. The "floating impeller" design requires lower starting torque and is less susceptible to the negative impact of sand and other abrasive materials contained in the water.

The shaft coupling is made of sintered AISI 304 stainless steel according to NEMA specifications, guaranteeing a precise connection with the electric motor and long-term, trouble-free operation of the entire drive system.