PartsTable TECHNICAL DATA SHEET
JULY 2026Technical Data Sheet

66191Valve,safety Relief

Anderson Greenwood Lp Dba Anderson Greenwood Crosby · NSN 4820-00-202-8260 · FSC 4820 · No Item Name Available
Verified by PartsTable
NSN 4820-00-202-8260 — this item is cataloged by the U.S. Government under National Stock Number 4820-00-202-8260. Primary manufacturer part number: 66191.
Features
  • Valve,safety Relief — FSC 4820
  • Face to Face Distance: 3.375 INCHES IN
  • Bolt Hole Nominal Diameter: 0.562 INCHES SECOND END IN
  • Flange Face Design: PLAIN SECOND END
  • Bolt Circle Nominal Diameter: 3.125 INCHES SECOND END IN
  • Nominal Outside Diameter: 4.250 INCHES SECOND END IN
  • Connection Type: FLANGE SECOND END
  • Bolt Hole Quantity: 4 FIRST END
Applications
  • Flow control in piping systems
  • Pressure regulation
  • Steam and fluid isolation
General Description

The Valve,safety Relief, cataloged under National Stock Number 4820-00-202-8260, is classified within Federal Supply Class 4820 (No Item Name Available) of the Valves group. The primary manufacturer of record is Anderson Greenwood Lp Dba Anderson Greenwood Crosby. Government technical data includes 30 verified specifications, sourced from the Federal Logistics Information System (FLIS). This item has 2 commercial cross-references from 2 manufacturers, enabling identification through both NSN and commercial part number lookups. 5 verified substitutes exist in the FLIS interchangeability database. Current acquisition status: Active.

Technical Specifications
ParameterValue
NSN4820-00-202-8260
Primary Part Number66191
Item NameValve,safety Relief
FSC / FSG4820 / 48 — No Item Name Available
ManufacturerAnderson Greenwood Lp Dba Anderson Greenwood Crosby
StatusACTIVE
Face to Face Distance3.375 INCHES IN
Bolt Hole Nominal Diameter0.562 INCHES SECOND END IN
Flange Face DesignPLAIN SECOND END
Bolt Circle Nominal Diameter3.125 INCHES SECOND END IN
Nominal Outside Diameter4.250 INCHES SECOND END IN
Connection TypeFLANGE SECOND END
Bolt Hole Quantity4 FIRST END
Maximum Operating Temp150.0 FAHRENHEIT SINGLE RESPONSE DEGF
Valve Operation MethodAUTOMATIC
Bolt Circle Nominal Diameter3.500 INCHES FIRST END IN
Flange ShapeROUND WITH HOLES SECOND END
Media for Which DesignedWATER-OIL-GAS SINGLE RESPONSE
Flange ShapeROUND WITH HOLES FIRST END
Bolt Circle Nominal Diameter3.500 INCHES FIRST END IN
Operating Pressure900.0 POUNDS PER SQUARE INCH (PSI) MAXIMUM SINGLE RESPONSE LBS
Media for Which DesignedWATER-OIL-GAS SINGLE RESPONSE
Face to Face Distance3.375 INCHES IN
First Connection Face to Centerline Distance3.750 INCHES IN
Flange Face DesignRAISED STRAIGHT FIRST END
Bolt Hole Nominal Diameter0.687 INCHES FIRST END IN
Nominal Outside Diameter4.875 INCHES FIRST END IN
Style DesignatorANGLE
Adjustable Pressure Range+558.0 TO 677.0 POUNDS PER SQUARE INCH LBS
Bolt Hole Quantity4 SECOND END
Features ProvidedPRESSURE TIGHT OUTLET SIDE
Style DesignatorANGLE
Disk Loading MethodSPRING
Flow Control DevicePOPPET
First Connection Face to Centerline Distance3.750 INCHES IN
Features ProvidedPRESSURE TIGHT OUTLET SIDE
Lifecycle & Compliance
Acquisition StatusACTIVE
HAZMATNo
Verified Substitutes 5
5342-01-038-2710 INTERCHANGEABLE
Mount,resilient,weapon System
5360-01-119-485199136453 INTERCHANGEABLE
Spring
Alfa Laval Inc
1650-01-473-1479 INTERCHANGEABLE
Motor,hydraulic
6550-01-554-291666191 INTERCHANGEABLE
Gn-6 Metricel Membrane Filter
Pall Gelman Laboratory
5315-01-608-243366191 INTERCHANGEABLE
Pin,straight,headed
Fastenal Company Dba Fastenal Co
Cross-Reference Index
Part NumberManufacturer
66191 PRIMARY Anderson Greenwood Lp Dba Anderson Greenwood Crosby (USA)
66191 Kunkle Industries Inc Lonergan Valve Div (USA)
Related Parts
5342-01-038-2710INTERCHANGEABLE
MOUNT,RESILIENT,WEAPON SYSTEM
5360-01-119-4851INTERCHANGEABLE
SPRING
99136453
1650-01-473-1479INTERCHANGEABLE
MOTOR,HYDRAULIC
6550-01-554-2916INTERCHANGEABLE
GN-6 METRICEL MEMBRANE FILTER
66191
5315-01-608-2433INTERCHANGEABLE
PIN,STRAIGHT,HEADED
66191

Frequently Asked Questions

What is NSN 4820-00-202-8260?

NSN 4820-00-202-8260 is a Valve,safety Relief, manufactured by Anderson Greenwood Lp Dba Anderson Greenwood Crosby, classified under FSC 4820 (No Item Name Available). Status: active.

What are the part numbers for NSN 4820-00-202-8260?

NSN 4820-00-202-8260 has 2 cross-referenced part numbers: 66191 (Anderson Greenwood Lp Dba Anderson Greenwood Crosby), 66191 (Kunkle Industries Inc Lonergan Valve Div).

What NSN replaces 4820-00-202-8260?

There are 5 known substitutes for 4820-00-202-8260: 5342-01-038-2710, 5360-01-119-4851, 1650-01-473-1479 and 2 more. Verify interchangeability with system specifications before substitution.

What are the specifications of 66191?

Key specifications for 66191: Face to Face Distance: 3.375 INCHES IN; Bolt Hole Nominal Diameter: 0.562 INCHES SECOND END IN; Flange Face Design: PLAIN SECOND END; Bolt Circle Nominal Diameter: 3.125 INCHES SECOND END IN. 30 total characteristics are documented in the Federal Logistics Information System.

Validated with multiple authoritative sources, including Government, OEM, and Certified sources.
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