Series 4280

Summary

Product identification

The Armstrong Series 4280 are motor-mounted, single-stage, single-end suction centrifugal pumps with rising head characteristics to pump shut-off. They are designed for horizontal end suction applications.

Operating limits

Pressure/Temperature Chart (based on clear, clean water):

• Cast Iron (ANSI 125 flanges):
  • 0 psig (0 bar) at 0°F (-18°C)
  • 100 psig (6.90 bar) at 50°F (10°C)
  • 150 psig (10.34 bar) at 100°F (38°C)
  • 175 psig working pressure at 140°F
  • 200 psig (13.79 bar) at 150°F (66°C)
  • 250 psig (17.24 bar) at 200°F (93°C)
  • 50 psig (3.45 bar) at 250°F (121°C)
• Ductile Iron (ANSI 250 flanges):
  • Up to 250 psig working pressure
  • 0 psig (0 bar) at 0°F (-18°C)
  • 100 psig (6.90 bar) at 50°F (10°C)
  • 150 psig (10.34 bar) at 100°F (38°C)
  • 200 psig (13.79 bar) at 150°F (66°C)
  • 250 psig (17.24 bar) at 200°F (93°C)
  • 300 psig (20.00 bar) at 250°F (121°C)

Notes:

• Hydrostatic test pressure at ambient temperature is 150% maximum working pressure.
• All values are based on clear, clean water. Values may change with other liquids.

Feed water

• Values are based on clear, clean water.
• For glycols above 30% by weight, specific mechanical seal materials are required.

Electrical

• Motor power requirements are minimum acceptable, sized for continuous operation without exceeding full load nameplate rating over the entire pump curve, exclusive of service factor.
• Motor is equipped with heavy-duty, grease-lubricated ball bearings.

Mechanical / hydraulic

Design Features:

• Easy maintenance due to back pull-out design.
• Extensive interchangeability of parts.
• Manufactured and inspected to rigid standards.
• Quiet operation.
• Self-venting center-line discharge prevents vapor lock.
• Confined casing gasket.
• Drilled and tapped gauge connections are standard on suction and discharge ports.
• Mount with motor feet, or motor and pump feet for convenience.

Components:

• Motor: Equipped with heavy-duty, grease-lubricated ball bearings rated to accommodate impeller radial loads and residual hydraulic thrusts.
• Mechanical Seal: Self-lubricating, single spring inside type. Provides positive sealing up to full design pressure.
  • Standard: Resin bonded carbon face rotating against a stationary silicone carbide seat.
  • For liquids above 200°F (93°C): Antimony loaded carbon face.
  • For glycols above 30% by weight: Silicon carbide face.
  • Elastomer: EPDM.
  • Spring and hardware: Stainless steel.
  • Shaft sleeve extends the full length of the mechanical seal area.
• Bracket: Heavy cylindrical bracket with 360-degree register on both flanges provides rigid union of pump and motor and establishes perfect alignment.
• Impeller: Fully enclosed, dynamically balanced, designed with balancing chamber and pressure relief holes to reduce axial thrusts to a minimum.
• Casing: Radially-split with center-line discharge. Can be left in the line while servicing the pump. Equipped with drilled and tapped drain connection and pressure gauge connections. Double volute design where radial loads demand.
  • Cast iron casing suitable for 175 psig working pressure at 140°F.
  • Ductile iron casing for pressures to 250 psig.
  • Hydrostatically tested to 150% maximum working pressure.
• Shaft: Impeller is mounted on an extension of the motor shaft with minimum overhang. A shaft sleeve affords protection in the wetted area.

Materials of Construction:

• Pump Flange Rating: 125 psig, 250 psig
• Construction Options:
  • Bronze fitted (bf)
  • All iron (ai)
  • All bronze (ab)
  • Bronze fitted, ductile casing and adapter bracket (dbf)
• Specific Materials:
  • Casing: Cast iron (ASTM A48 Class 30), Cast ductile iron (ASTM A536 Grade 65-45-12)
  • Impeller: Cast bronze (ASTM B584 Grade C84400), Cast iron (ASTM A48 Class 30), Cast ductile iron (ASTM A536 Grade 65-45-12)
  • Capscrew (impeller): AISI 1010-1018 Type 316 (ss-5)
  • Washer (impeller): ASTM A564 Type 18-8 (ss-2)
  • Gasket (casing): Fiber (F)
  • Adapter bracket: Cast iron (ASTM A48 Class 30), Cast ductile iron (ASTM A536 Grade 65-45-12)
  • Motor shaft: Carbon steel (S)
  • Shaft sleeve: Hard brass tubing (ASTM B111.687), Cast bronze (ASTM B584 Grade C84400)
  • Water slinger: Cast bronze (ASTM B584 Grade C84400)
  • Seal washer: ASTM A564 Type 18-8 (ss-2)
  • Seal seat: Silicone carbide (SiC)
  • Seal hardware: ASTM A564 Type 18-8 (ss-2)
  • Seal elastomer: EPDM elastomer (ep)
  • Seal spring: AISI 1010-1018 Type 316 (ss-5)
  • Seal face: Resin bonded carbon (C), Silicon carbide (SiC)

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Disclaimer: This summary is based on extracted text and may not include all figures, footnotes, or the latest revisions from the complete OEM PDF datasheet. Contractual data for any project must always match the specific OEM PDF revision used for that project.

Official datasheet (PDF)

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