{"product_id":"grundfos-nb-50-125-121-cast-iron-4-kw-end-suction-centrifugal-pump-with-closed-impeller","title":"Grundfos NB 50-125\/121 Cast Iron 4 kW End Suction Centrifugal Pump with Closed Impeller","description":"\u003cp\u003eSpecified for commercial building services, process water loops, and district cooling infrastructure, the NB 50-125\/121 end-suction centrifugal pump incorporates DN 65 suction and DN 50 discharge flanged ports. The end-suction volute design connects directly to suction line headers and concrete foundation bases.\u003c\/p\u003e\u003cp\u003eAt nominal operational speed, hydraulic output provides 1148 L\/Min flow throughput alongside a maximum head limit of 14.15 m. Structural construction incorporates an EN-GJL-250 cast iron body with cataphoresis surface finish. Internal components feature a stainless steel impeller and BQQE seal. Total net weight stands at 71 kg.\u003c\/p\u003e\u003cp\u003eThe NB 50-125\/121 electric motor operates on a 415 V three-phase supply drawing 7.82 Amps rated current at 4 kW output power. Fluid handling parameters accommodate liquid temperatures between -25°C to 120°C up to 16 bar system pressure. Line connection uses opposite DN 65 inlet and DN 50 outlet flanged ports.\u003c\/p\u003e\u003cp\u003eEnclosure protection on the NB 50-125\/121 model meets IP55 standards while motor windings feature Class F insulation and PTC thermistor protection relays. Maintenance technicians can extract the drive unit using back-pull-out access without removing the cast iron volute casing from connected plant room piping manifolds.\u003c\/p\u003e\u003cp\u003e\u003cstrong\u003eFeatures\u003c\/strong\u003e\u003c\/p\u003e\u003cul\u003e\n\u003cli\u003eEN733 and ISO2858 dimensional compliance ensures interchangeability with other standard end-suction pumps across commercial and industrial installations.\u003c\/li\u003e\n\u003cli\u003eATEX Zone 1, 2, 21 or 22 certification available for operation in potentially explosive atmospheres (except E-model variants).\u003c\/li\u003e\n\u003cli\u003eIntegrally cast suction and discharge ports with dedicated vent and drain ports provide direct connection points without additional fittings.\u003c\/li\u003e\n\u003cli\u003eNo baseplate or grouting required to maintain correct shaft alignment and vibration levels within Hydraulic Institute standards.\u003c\/li\u003e\n\u003cli\u003eCataphoretic electrocoating on cast iron internal surfaces provides barrier protection against oxidative corrosion in hydronic circulation loops.\u003c\/li\u003e\n\u003cli\u003eClose-coupled configuration eliminates coupling alignment procedures and reduces overall installation footprint compared to long-coupled alternatives.\u003c\/li\u003e\n\u003cli\u003eBall bearing support arrangement accommodates both radial and axial thrust loads generated during continuous duty operation at rated speed.\u003c\/li\u003e\n\u003c\/ul\u003e\u003cp\u003e\u003cstrong\u003eIMPORTANT:\u003c\/strong\u003eBulk freight charges apply. Please contact us for a freight quote before ordering.\u003c\/p\u003e","brand":"Grundfos","offers":[{"title":"Default Title","offer_id":51148677906679,"sku":"93209292","price":4445.93,"currency_code":"AUD","in_stock":true}],"thumbnail_url":"\/\/cdn.shopify.com\/s\/files\/1\/0927\/0116\/3767\/files\/grundfos-nb-50-125-121-cast-iron-4-kw-end-suction-centrifugal-pump-with-closed-impeller.png?v=1789124269","url":"https:\/\/foundationpumps.com.au\/products\/grundfos-nb-50-125-121-cast-iron-4-kw-end-suction-centrifugal-pump-with-closed-impeller","provider":"Foundation Pumps","version":"1.0","type":"link"}