Centrifugal pump SRG series

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Grundfos SRG recirculation pumps are designed for the pumping of sludge from one tank to another in sewage treatment plants and for other pump applications involving a high flow rate and low head. The Grundfos range of horizontal submersible SRG recirculation pumps is designed for pumping return sludge in wastewater treatment plants and other applications where large flow rates are required at a low head. The recirculation pumps are equipped with a gear-driven energy-efficient impeller. The squirrel-cage induction motor is protected against overload by means of three bi-metallic thermal switches (PTO) in the motor windings. The products are equipped with IE3 motor components. To prevent ingress of the surrounding liquid, the SRG recirculation pumps have two radial FKM rubber lip seals in combination with a ceramic wear ring and a mechanical shaft seal made of silicon carbide/silicon carbide or tungsten carbide/tungsten carbide, depending on size. The secondary seal between the gearbox and the motor is made of carbon/aluminium oxide. The oil-filled gearbox is monitored for ingress of water by a leak sensor incorporated as standard. The sensor can trigger an alarm signal and/or switch off the motor by means of an external Grundfos relay, type ALR-20/A, supplied as an optional accessory. The gearbox incorporates tapered roller bearings absorbing the axial force from the propeller. Motors range from 0.8 to 24 kW. A wide range of accessories made of stainless steel AISI 304/316 steel ensure easy installation and long trouble-free operation.