ASCO 551 Series Solenoid Spool Valve

Brand: ASCO

The ASCO Series 551, also known as 8551, is a line of 1/4" 3-way and 4-way compact solenoid spool valves that are ideal for controlling air or inert gas in challenging environments.
 
The valves' unique design combines hard T-seals and flexible O-rings that provide bubble-tight shutoff, dirt resistance, and multi-million cycle reliability.
 
The 551 Series comes in anodized aluminum, brass, and stainless steel bodies with 1/4-inch NPT and BSP connections.
 
It is suitable for the harsh conditions found in chemicals, refining, food & beverage applications and life science processing.
Features
  • Available in two versions, mounted directly to actuators with NAMUR interface per VDI/VDE 3845 or threaded to mount on the pipe
  • Valve body in Aluminum, Brass, or Stainless steel 316L
  • Exhaust ports are pipeable, providing better protection against harsh environments
  • DIN, watertight, and explosion-proof solenoids are available for use in mission-critical and hazardous areas
  • Low-power constructions are ideal for remote and alternative power locations
  • Integral breather block vents to spring side of the actuator to exhaust, preventing corrosion
  • Single- and dual-solenoid constructions are available that mount in any position
  • Global Ex approvals; ATEX, IEC EX, NEPSI, CUTR, KOSHA, UL, CSA, InMetro
  • All ports of NAMUR on the same side for a better water , DUST protection
  • Available will all Explosion proof solenoids: Ex d, Ex mb, Ex ia/Ib, Ex e mb, NEMA
  • Available in an arctic version, suitable for use in temperatures as low as -60°C
  • Compact spool valve convertible from 3/2 to 5/2 with a single flow plate design (551 Series only)

Specifications

Brand

Valve Actuation

  • Solenoid - Air Pilot

Body Material

  • Brass, Stainless Steel, Aluminum

Media

  • Air, Inert Gas

Pipe / Port Size

  • 1/4"

Port Type

  • G ISO228 / 1-G BSPP, Female NPT

Function

  • 3-Way - 3/2 Normally Closed
  • 4-Way - 5/2, 4-Way - 5/3 - Closed Center
  • 4-Way - 5/3 - Open Center

Flow

  • From 0.5 Cv to 1.0 Cv, from 0.43 Kv to 0.86 Kv

Voltage

  • 24 AC, 110 AC, 120 AC, 220 AC, 480 AC, 6 DC, 12 DC, 24 DC, 120 DC, 240 DC / 50, 60

Maximum Differential, Maximum Operating Pressure

  • Vacuum to 150 psig

Operating Environment

  • Corrosive, Hazardous, Indoor, Outdoor

Standards & Regulations

  • ATEX Zone 1-21, ATEX Zone 2-22, Class I Div. 1, Class II Div. 1, SIL, Type 1, Type 2, Type 3, Type 3S, Type 4, Type 4X, Type 6, Type 6P, Type 7, Type 9

Temperature

  • -60° to 80° C

Documentation

Catalogs

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