4280 Motor Mounted Pumps

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4280 motor mounted pump
4280 motor mounted pump Sideview
4280 motor mounted pumps Line drawing

  • Summary
  • Applications

    HVAC-system pumping; light industrial/ process pumping

  • Description

    The Armstrong 4280 horizontal end-suction pumps are equipped with close-coupled motors to minimize footprint requirements.

  • Materials
    • Cast iron, ductile iron, or bronze casing
    • Cast iron or bronze impeller
  • Configuration

    Inside single-spring mechanical seal

  • Performance range

    Up to 2,000 USgpm (125 L/s) flow; up to 400 ft (120 m)

  • Temperature

    250°F (121°C)

  • Power Range

    0.33 hp to 60 hp (0.25 kW to 45 kW)

  • Size

    1" to 6” (25 mm to 150 mm)

Best-in-class design

  • ANSI style centerline discharge casing eliminates casing vapor lock 
  • Sintered silicon carbide mechanical seal seat for longer life 
  • Confined casing gasket eliminates blow-outs 
  • Pre-lubricated and sealed ball bearings for convenient installation (simply pipe, align, wire and start) 
  • Motor feet mounting only needed with over-hung casing 
  • Compact design

Low energy consumption

  • Armstrong 4280 pumps are equipped with high-efficiency NEMA-premium motors for significant reduction in energy consumption and cost
  • All motors are suitable for inverter-fed service



Low operating risk and cost

  • Universal replacement seals, bearings, and motors available locally world-wide 
  • ANSI-style centerline discharge casing eliminates air binding 
  • Pre-lubricated and sealed ball bearings eliminate lubrication requirements
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