PartsTable TECHNICAL DATA SHEET
JULY 2026Technical Data Sheet

5173A-4TB-350Valve,safety Relief

Circor Aerospace, Inc. Dba Circor Aerospace Inc · NSN 4820-00-776-6886 · FSC 4820 · No Item Name Available
Verified by PartsTable
NSN 4820-00-776-6886 — this item is cataloged by the U.S. Government under National Stock Number 4820-00-776-6886. Primary manufacturer part number: 5173A-4TB-350.
Features
  • Valve,safety Relief — FSC 4820
  • Connection Style: GASKET SEAL(BOSS) SECOND END
  • Thread Class: 3B SECOND END
  • Connection Style: FLARED (TUBE) FIRST END
  • Thread Series Designator: UNF SECOND END
  • Thread Direction: RIGHT-HAND SECOND END
  • Flow Control Device: POPPET
  • Opening Pressure Setting: 350.0 POUNDS PER SQUARE INCH LBS
Applications
  • Flow control in piping systems
  • Pressure regulation
  • Steam and fluid isolation
  • Applications requiring Aluminum Alloy Overall construction
General Description

The Valve,safety Relief, cataloged under National Stock Number 4820-00-776-6886, is classified within Federal Supply Class 4820 (No Item Name Available) of the Valves group. The primary manufacturer of record is Circor Aerospace, Inc. Dba Circor Aerospace Inc. Government technical data includes 25 verified specifications, sourced from the Federal Logistics Information System (FLIS). This item has 10 commercial cross-references from 7 manufacturers, enabling identification through both NSN and commercial part number lookups. 8 verified substitutes exist in the FLIS interchangeability database. Current acquisition status: Active.

Technical Specifications
ParameterValue
NSN4820-00-776-6886
Primary Part Number5173A-4TB-350
Item NameValve,safety Relief
FSC / FSG4820 / 48 — No Item Name Available
ManufacturerCircor Aerospace, Inc. Dba Circor Aerospace Inc
StatusACTIVE
Connection StyleGASKET SEAL(BOSS) SECOND END
Thread Class3B SECOND END
Connection StyleFLARED (TUBE) FIRST END
Thread Series DesignatorUNF SECOND END
Thread DirectionRIGHT-HAND SECOND END
Flow Control DevicePOPPET
Opening Pressure Setting350.0 POUNDS PER SQUARE INCH LBS
Thread Series DesignatorUNIFIED NATIONAL JOINT FINE (UNJF) FIRST END
MaterialALUMINUM ALLOY OVERALL
Surface TreatmentANODIZE LOCATION NOT OTHERWISE SPECIFIED
Seat Angle37.0 DEGREES FIRST END
Nominal Thread Size0.437 INCHES FIRST END IN
Style DesignatorSTRAIGHT THRU NOTE: TO BE USED FOR VALVE BODIES OF ONE SECTION ONLY.
Operating Pressure2500.0 POUNDS PER SQUARE INCH (PSI) MAXIMUM SINGLE RESPONSE LBS
Media for Which DesignedHYDRAULIC FLUID, SILICATE-ESTER BASE SINGLE RESPONSE
Disk Loading MethodSPRING
Nominal Thread Size0.438 INCHES SECOND END IN
Connection TypeTHREADED EXTERNAL TUBE FIRST END
Features ProvidedPRESSURE TIGHT OUTLET SIDE
Maximum Operating Temp300.0 FAHRENHEIT SINGLE RESPONSE DEGF
Thread DirectionRIGHT-HAND FIRST END
Connection TypeTHREADED INTERNAL BOSS SECOND END
Adjustable Pressure Range+265.0 TO 380.0 POUNDS PER SQUARE INCH LBS
Thread Class3A FIRST END A
Valve Operation MethodAUTOMATIC
Lifecycle & Compliance
Acquisition StatusACTIVE
HAZMATNo
Verified Substitutes 8
5360-00-003-393727391 INTERCHANGEABLE
Spring,helical,compression
Eaton Corporation Dba Airframe Div Fuel & Motion Control Systems
3020-00-541-741827391 INTERCHANGEABLE
Sprocket Wheel
L3harris Technologies, Inc.
3110-00-702-155627391 INTERCHANGEABLE
Bearing,roller,cylindrical
Skf Usa Inc.
5935-00-801-20582739-1 INTERCHANGEABLE
Connector,receptacle,electrical
Microwave Devices Inc
5910-00-869-63732739-1 INTERCHANGEABLE
Capacitor,fixed,plastic Dielectr
Northrop Grumman Systems Corporation Dba Northrop Grumman Systems Corp Div Multiple
5325-01-191-615427391 INTERCHANGEABLE
Insert,screw Thread
Moog Inc. Dba Ampac-Isp Corp
4820-01-248-999927391 INTERCHANGEABLE
Valve,gate
Crane Co Div Valve Div
6160-01-600-075882026 INTERCHANGEABLE
Retainer,battery
R.g. Enterprises (u.s.a.), Inc. Dba Rg Enterprises Inc
Cross-Reference Index
Part NumberManufacturer
D8497-63-1 Chief of Engineers Dept of Army (USA)
D8497-63-1 Cecom Lr Center (USA)
5173A-4TB-350 PRIMARY Circor Aerospace, Inc. Dba Circor Aerospace Inc (USA)
D8497-63-1 Drs Environmental Systems Inc (USA)
8497-63-1 Chief of Engineers Dept of Army (USA)
5183A4TB350 Circor Aerospace, Inc. Dba Circor Aerospace Inc (USA)
D8497-63-1 Hdt Expeditionary Systems Inc (USA)
D8497-63-1 Keco Industries, Inc. (USA)
8497-63-1 Cecom Lr Center (USA)
27391 Triumph Thermal Systems - Maryland, Inc. (USA)
Related Parts
5360-00-003-3937INTERCHANGEABLE
SPRING,HELICAL,COMPRESSION
27391
3020-00-541-7418INTERCHANGEABLE
SPROCKET WHEEL
27391
3110-00-702-1556INTERCHANGEABLE
BEARING,ROLLER,CYLINDRICAL
27391
5935-00-801-2058INTERCHANGEABLE
CONNECTOR,RECEPTACLE,ELECTRICAL
2739-1
5910-00-869-6373INTERCHANGEABLE
CAPACITOR,FIXED,PLASTIC DIELECTR
2739-1
5325-01-191-6154INTERCHANGEABLE
INSERT,SCREW THREAD
27391
4820-01-248-9999INTERCHANGEABLE
VALVE,GATE
27391
6160-01-600-0758INTERCHANGEABLE
RETAINER,BATTERY
82026

Frequently Asked Questions

What is NSN 4820-00-776-6886?

NSN 4820-00-776-6886 is a Valve,safety Relief, manufactured by Circor Aerospace, Inc. Dba Circor Aerospace Inc, classified under FSC 4820 (No Item Name Available). Status: active.

What are the part numbers for NSN 4820-00-776-6886?

NSN 4820-00-776-6886 has 10 cross-referenced part numbers: D8497-63-1 (Chief of Engineers Dept of Army), D8497-63-1 (Cecom Lr Center), 5173A-4TB-350 (Circor Aerospace, Inc. Dba Circor Aerospace Inc), D8497-63-1 (Drs Environmental Systems Inc), 8497-63-1 (Chief of Engineers Dept of Army) and 5 more.

What NSN replaces 4820-00-776-6886?

There are 8 known substitutes for 4820-00-776-6886: 5360-00-003-3937, 3020-00-541-7418, 3110-00-702-1556 and 5 more. Verify interchangeability with system specifications before substitution.

What are the specifications of 5173A-4TB-350?

Key specifications for 5173A-4TB-350: Connection Style: GASKET SEAL(BOSS) SECOND END; Thread Class: 3B SECOND END; Connection Style: FLARED (TUBE) FIRST END; Thread Series Designator: UNF SECOND END. 25 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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