Flygt N 3312

The Flygt N 3312 high-capacity wastewater pump series takes on the toughest sewage pumping applications with minimal downtime and high energy-efficiency. Self-cleaning N-technology hydraulics provide up to 25% energy savings compared to conventional hydraulics and are available in Hard-Iron, grey iron, or stainless steel.

Submersible and dry installation options (configurations P, S, T, and Z), as well as explosion-proof versions, provide flexibility for pump station design. The optional premium efficiency motor can help meet regulatory requirements.

Clog-free pumping with Flygt N-hydraulics 

Flygt N-hydraulics combine a semi-open dual-blade impeller with a unique geometry to provide sustained high efficiency and trouble-free operation. Backswept leading edges on the impeller vanes sweep solids from the center of the impeller to the perimeter, where they are caught in a relief groove and pushed out of the pump. 

Due to this mechanical self-cleaning design, soft, stringy fibers are no match for the Flygt N-pump and a sludge concentration up to 8% can easily be handled.

For applications with salt, sand infiltration and grit removal duties, Flygt’s Hard-Iron material can extend N-hydraulic life. 

Efficient cooling for motor protection 

Depending on operating environment, Flygt N 3312 pumps are available with several cooling options, including internal closed-loop cooling, direct cooling by the pumped media, and for warm-liquid applications, external cooling.

Flygt’s advanced closed-loop cooling system is suitable for dry, partially submerged, and fully submerged applications and allows use of premium efficiency motors. Heat from the stator is transferred to the coolant, which then circulates through the inner and outer cooling jacket and transfers the heat to the pumped media. Because the cooling system uses freeze-proof glycol cooling liquid and is completely sealed off, it is insensitive to both cold (down to -45°C) and impurities in the pumped media. 

Reliable, robust hardware

Operational reliability is paramount to public utilities, as unexpected events and pumping interruptions can have a significant impact on communities. That’s why Flygt gives great care to the design and manufacture of each component in its pumps. 

Flygt N 3312 pumps feature: 

• Self-cleaning N-impeller in Hard-Iron, hardened grey iron or duplex stainless steel
• Replaceable wear ring in Hard-Iron or grey iron 
• Short shaft overhang, reducing shaft deflection and increasing seal and bearing life
• Motor designed for submersible use, with Class H insulation and heat losses concentrated around the stator core for improved cooling properties 
  • Option of medium voltage motor up to 6.6 kV to reduce current and motor cable size
  • Option to upgrade to IE3-comparable premium efficiency motor
• Two sets of mechanical shaft seals that work independently to provide double the security, available in tungsten carbide (WCCR) or silicon carbide (SiC) depending on pumped media
• Active Seal micro-pumping grooves on the inner seal for zero leakage into the motor
• Thermal sensors in the stator windings; analog temperature sensor for the lower bearing; leakage sensors in the stator housing and junction box; and 3-axis vibration sensor – all as standard. Temperature sensor for the upper bearing as an option
• Flexible cooling options, including internal closed-loop cooling, direct cooling or for warm-liquid applications, external cooling
• SUBCAB^® motor cable specially developed for submersible use
• Flygt MAS 801 pump monitoring system option for a proactive approach to pump station diagnostics

Wet and dry installation packages

Flygt N-technology pumps are suitable for submerged or dry installation. Installation packages include key accessories and components to meet site-specific requirements and reduce costs.

Wet Pit (P)

​​Semi-permanent, submersible pump installation. Wet pit arrangement with the pump installed on twin guide bars with automatic connection to the discharge pipe.​​

Portable (S)

​​​Portable, submersible pump installation. Portable pump with hose coupling or flange for connection to the discharge pipe.​​

Dry Installation vertical (T)

​​​Vertical, permanent, dry pump installation. The submersible pump is installed in a dry pit, with flange connection to suction and discharge piping.​​

Dry Installation horizontal (Z)

​​​Horizontal, permanent, dry pump installation. The submersible pump is installed in a dry pit, with flange connection to suction and discharge piping. Optional sled mounting system provides safe, easy access for servicing the drive unit and impeller.

Expert advice for pump selection and station design 

When transporting water, wastewater and other fluids containing solids, the right pump and the right system design are critical to preventing problems like solids settling and pumps clogging. They can also deliver significant savings in energy consumption and maintenance costs. 

Xylem engineers pair decades of experience with digital pump station design tools to deliver optimized performance for your unique environment and operational requirements.